From 1a405442200ae9402c8c99ae206870390074eabf Mon Sep 17 00:00:00 2001 From: Mitchell Hashimoto Date: Mon, 4 Apr 2022 11:11:24 -0700 Subject: [PATCH] gb_math --- build.zig | 5 +- src/App.zig | 13 +- src/TextRenderer.zig | 5 + src/cglm.zig | 78 -- src/gb_math.c | 6 + src/gb_math.h | 2234 ++++++++++++++++++++++++++++++++++++++++++ src/gb_math.zig | 3 + 7 files changed, 2257 insertions(+), 87 deletions(-) delete mode 100644 src/cglm.zig create mode 100644 src/gb_math.c create mode 100644 src/gb_math.h create mode 100644 src/gb_math.zig diff --git a/build.zig b/build.zig index 3bd1722ed..258b83b14 100644 --- a/build.zig +++ b/build.zig @@ -3,7 +3,6 @@ const Builder = std.build.Builder; const LibExeObjStep = std.build.LibExeObjStep; const glfw = @import("vendor/mach/glfw/build.zig"); const ft = @import("src/freetype/build.zig"); -const cglm = @import("src/cglm.zig"); pub fn build(b: *std.build.Builder) !void { const target = b.standardTargetOptions(.{}); @@ -13,13 +12,13 @@ pub fn build(b: *std.build.Builder) !void { exe.setTarget(target); exe.setBuildMode(mode); exe.install(); + exe.addIncludeDir("src/"); + exe.addCSourceFile("src/gb_math.c", &.{}); exe.addPackagePath("glfw", "vendor/mach/glfw/src/main.zig"); glfw.link(b, exe, .{}); exe.linkSystemLibrary("epoxy"); - try cglm.build(b, exe, target, mode, .{}); - const ftlib = try ft.create(b, target, mode, .{}); ftlib.link(exe); // to link to system: diff --git a/src/App.zig b/src/App.zig index 9a0982f8e..784d390ef 100644 --- a/src/App.zig +++ b/src/App.zig @@ -32,12 +32,6 @@ pub fn init(alloc: std.mem.Allocator) !App { // renderer at some point. try glfw.makeContextCurrent(window); try glfw.swapInterval(1); - window.setSizeCallback((struct { - fn callback(_: glfw.Window, width: i32, height: i32) void { - log.info("set viewport {} {}", .{ width, height }); - try gl.viewport(0, 0, width, height); - } - }).callback); // Blending for text gl.c.glEnable(gl.c.GL_CULL_FACE); @@ -48,6 +42,13 @@ pub fn init(alloc: std.mem.Allocator) !App { var texter = try TextRenderer.init(alloc); errdefer texter.deinit(); + window.setSizeCallback((struct { + fn callback(_: glfw.Window, width: i32, height: i32) void { + log.info("set viewport {} {}", .{ width, height }); + try gl.viewport(0, 0, width, height); + } + }).callback); + return App{ .window = window, .text = texter, diff --git a/src/TextRenderer.zig b/src/TextRenderer.zig index b28ec1ae4..c55feeaf2 100644 --- a/src/TextRenderer.zig +++ b/src/TextRenderer.zig @@ -3,6 +3,7 @@ const TextRenderer = @This(); const std = @import("std"); const ftc = @import("freetype/c.zig"); const gl = @import("opengl.zig"); +const gb = @import("gb_math.zig"); alloc: std.mem.Allocator, ft: ftc.FT_Library, @@ -113,6 +114,10 @@ pub fn init(alloc: std.mem.Allocator) !TextRenderer { @embedFile("../shaders/text.f.glsl"), ); + // Our project + var proj: gb.gbMat4 = undefined; + gb.gb_mat4_ortho2d(&proj, 0, 640, 0, 480); + return TextRenderer{ .alloc = alloc, .ft = ft, diff --git a/src/cglm.zig b/src/cglm.zig deleted file mode 100644 index a839e9ede..000000000 --- a/src/cglm.zig +++ /dev/null @@ -1,78 +0,0 @@ -const std = @import("std"); - -/// Compile-time options for the library. These mostly correspond to -/// options exposed by the native build system used by the library. -pub const BuildOptions = struct {}; - -// Build and link this library. -pub fn build( - b: *std.build.Builder, - step: *std.build.LibExeObjStep, - target: std.zig.CrossTarget, - mode: std.builtin.Mode, - opts: BuildOptions, -) !void { - _ = opts; - - const ret = b.addStaticLibrary("cglm", null); - ret.setTarget(target); - ret.setBuildMode(mode); - - var flags = std.ArrayList([]const u8).init(b.allocator); - defer flags.deinit(); - - try flags.appendSlice(&.{ - "-DCGLM_STATIC", - }); - - // C files - ret.addCSourceFiles(srcs, flags.items); - ret.addIncludeDir(include_dir); - ret.linkLibC(); - - step.addIncludeDir(include_dir); - step.linkLibrary(ret); -} - -fn root() []const u8 { - return (std.fs.path.dirname(@src().file) orelse unreachable) ++ "/../vendor/cglm/"; -} - -/// Directories with our includes. -const include_dir = root() ++ "include"; - -const srcs = &.{ - root() ++ "src/euler.c", - root() ++ "src/affine.c", - root() ++ "src/io.c", - root() ++ "src/quat.c", - root() ++ "src/cam.c", - root() ++ "src/vec2.c", - root() ++ "src/vec3.c", - root() ++ "src/vec4.c", - root() ++ "src/mat2.c", - root() ++ "src/mat3.c", - root() ++ "src/mat4.c", - root() ++ "src/plane.c", - root() ++ "src/frustum.c", - root() ++ "src/box.c", - root() ++ "src/project.c", - root() ++ "src/sphere.c", - root() ++ "src/ease.c", - root() ++ "src/curve.c", - root() ++ "src/bezier.c", - root() ++ "src/ray.c", - root() ++ "src/affine2d.c", - root() ++ "src/clipspace/persp_lh_zo.c", - root() ++ "src/clipspace/persp_rh_zo.c", - root() ++ "src/clipspace/persp_lh_no.c", - root() ++ "src/clipspace/persp_rh_no.c", - root() ++ "src/clipspace/ortho_lh_zo.c", - root() ++ "src/clipspace/ortho_rh_zo.c", - root() ++ "src/clipspace/ortho_lh_no.c", - root() ++ "src/clipspace/ortho_rh_no.c", - root() ++ "src/clipspace/view_lh_zo.c", - root() ++ "src/clipspace/view_rh_zo.c", - root() ++ "src/clipspace/view_lh_no.c", - root() ++ "src/clipspace/view_rh_no.c", -}; diff --git a/src/gb_math.c b/src/gb_math.c new file mode 100644 index 000000000..9c2e74215 --- /dev/null +++ b/src/gb_math.c @@ -0,0 +1,6 @@ +// This file defines the implementation of gb_math and is compiled using clang. +// gb_math.zig then imports gb_math.h without the implementation define set +// so that it can just get the function prototypes. + +#define GB_MATH_IMPLEMENTATION +#include "gb_math.h" diff --git a/src/gb_math.h b/src/gb_math.h new file mode 100644 index 000000000..9f405c699 --- /dev/null +++ b/src/gb_math.h @@ -0,0 +1,2234 @@ +/* gb_math.h - v0.07c - public domain C math library - no warranty implied; use at your own risk + A C math library geared towards game development + use '#define GB_MATH_IMPLEMENTATION' before including to create the implementation in _ONE_ file + +Version History: + 0.07f - Fix constants + 0.07e - Fixed a warning + 0.07d - Fix mat4_inverse + 0.07c - Add gb_random01 + 0.07b - Fix mat4_inverse + 0.07a - Fix Mat2 + 0.07 - Better Mat4 procedures + 0.06h - Ignore silly warnings + 0.06g - Remove memzero + 0.06f - Remove warning on MSVC + 0.06e - Change brace style and fix some warnings + 0.06d - Bug fix + 0.06c - Remove extra needed define for C++ and inline all operators + 0.06b - Just formatting + 0.06a - Implement rough versions of mod, remainder, copy_sign + 0.06 - Windows GCC Support and C90-ish Support + 0.05 - Less/no dependencies or CRT + 0.04d - License Update + 0.04c - Use 64-bit murmur64 version on WIN64 + 0.04b - Fix strict aliasing in gb_quake_rsqrt + 0.04a - Minor bug fixes + 0.04 - Namespace everything with gb + 0.03 - Complete Replacement + 0.01 - Initial Version + +LICENSE + This software is dual-licensed to the public domain and under the following + license: you are granted a perpetual, irrevocable license to copy, modify, + publish, and distribute this file as you see fit. +WARNING + - This library is _slightly_ experimental and features may not work as expected. + - This also means that many functions are not documented. + +CONTENTS + - Common Macros + - Types + - gbVec(2,3,4) + - gbMat(2,3,4) + - gbFloat(2,3,4) + - gbQuat + - gbRect(2,3) + - gbAabb(2,3) + - gbHalf (16-bit floating point) (storage only) + - Operations + - Functions + - Type Functions + - Random + - Hash +*/ + +#ifndef GB_MATH_INCLUDE_GB_MATH_H +#define GB_MATH_INCLUDE_GB_MATH_H + +#include + +#if !defined(GB_MATH_NO_MATH_H) + #include +#else + #include +#endif + +#ifndef GB_MATH_DEF + #ifdef GB_MATH_STATIC + #define GB_MATH_DEF static + #else + #define GB_MATH_DEF extern + #endif +#endif + +#if defined(_MSC_VER) +#pragma warning(push) +#pragma warning(disable:4201) +#endif + +typedef union gbVec2 { + struct { float x, y; }; + float e[2]; +} gbVec2; + +typedef union gbVec3 { + struct { float x, y, z; }; + struct { float r, g, b; }; + + gbVec2 xy; + float e[3]; +} gbVec3; + +typedef union gbVec4 { + struct { float x, y, z, w; }; + struct { float r, g, b, a; }; + struct { gbVec2 xy, zw; }; + gbVec3 xyz; + gbVec3 rgb; + float e[4]; +} gbVec4; + + + +typedef union gbMat2 { + struct { gbVec2 x, y; }; + gbVec2 col[2]; + float e[4]; +} gbMat2; + +typedef union gbMat3 { + struct { gbVec3 x, y, z; }; + gbVec3 col[3]; + float e[9]; +} gbMat3; + +typedef union gbMat4 { + struct { gbVec4 x, y, z, w; }; + gbVec4 col[4]; + float e[16]; +} gbMat4; + + +typedef union gbQuat { + struct { float x, y, z, w; }; + gbVec4 xyzw; + gbVec3 xyz; + float e[4]; +} gbQuat; + + +#if defined(_MSC_VER) +#pragma warning(pop) +#endif + +typedef float gbFloat2[2]; +typedef float gbFloat3[3]; +typedef float gbFloat4[4]; + + +typedef struct gbRect2 { gbVec2 pos, dim; } gbRect2; +typedef struct gbRect3 { gbVec3 pos, dim; } gbRect3; + +typedef struct gbAabb2 { gbVec2 centre, half_size; } gbAabb2; +typedef struct gbAabb3 { gbVec3 centre, half_size; } gbAabb3; + +#if defined(_MSC_VER) + typedef unsigned __int32 gb_math_u32; + typedef unsigned __int64 gb_math_u64; +#else + #if defined(GB_USE_STDINT) + #include + typedef uint32_t gb_math_u32; + typedef uint64_t gb_math_u64; + #else + typedef unsigned int gb_math_u32; + typedef unsigned long long gb_math_u64; + #endif +#endif + +typedef short gbHalf; + + +#ifndef GB_MATH_CONSTANTS +#define GB_MATH_CONSTANTS + #define GB_MATH_EPSILON 1.19209290e-7f + #define GB_MATH_ZERO 0.0f + #define GB_MATH_ONE 1.0f + #define GB_MATH_TWO_THIRDS 0.666666666666666666666666666666666666667f + + #define GB_MATH_TAU 6.28318530717958647692528676655900576f + #define GB_MATH_PI 3.14159265358979323846264338327950288f + #define GB_MATH_ONE_OVER_TAU 0.159154943091895335768883763372514362f + #define GB_MATH_ONE_OVER_PI 0.318309886183790671537767526745028724f + + #define GB_MATH_TAU_OVER_2 3.14159265358979323846264338327950288f + #define GB_MATH_TAU_OVER_4 1.570796326794896619231321691639751442f + #define GB_MATH_TAU_OVER_8 0.785398163397448309615660845819875721f + + #define GB_MATH_E 2.7182818284590452353602874713526625f + #define GB_MATH_SQRT_TWO 1.41421356237309504880168872420969808f + #define GB_MATH_SQRT_THREE 1.73205080756887729352744634150587236f + #define GB_MATH_SQRT_FIVE 2.23606797749978969640917366873127623f + + #define GB_MATH_LOG_TWO 0.693147180559945309417232121458176568f + #define GB_MATH_LOG_TEN 2.30258509299404568401799145468436421f +#endif + + +#if defined(__cplusplus) +extern "C" { +#endif + +#ifndef gb_clamp +#define gb_clamp(x, lower, upper) (gb_min(gb_max(x, (lower)), (upper))) +#endif +#ifndef gb_clamp01 +#define gb_clamp01(x) gb_clamp(x, 0, 1) +#endif + +#ifndef gb_square +#define gb_square(x) ((x)*(x)) +#endif + +#ifndef gb_cube +#define gb_cube(x) ((x)*(x)*(x)) +#endif + +#ifndef gb_abs +#define gb_abs(x) ((x) > 0 ? (x) : -(x)) +#endif + +#ifndef gb_sign +#define gb_sign(x) ((x) >= 0 ? 1 : -1) +#endif + + +GB_MATH_DEF float gb_to_radians(float degrees); +GB_MATH_DEF float gb_to_degrees(float radians); + +/* NOTE(bill): Because to interpolate angles */ +GB_MATH_DEF float gb_angle_diff(float radians_a, float radians_b); + +#ifndef gb_min +#define gb_min(a, b) ((a) < (b) ? (a) : (b)) +#endif +#ifndef gb_max +#define gb_max(a, b) ((a) > (b) ? (a) : (b)) +#endif + +#ifndef gb_min3 +#define gb_min3(a, b, c) gb_min(gb_min(a, b), c) +#endif + +#ifndef gb_max3 +#define gb_max3(a, b, c) gb_max(gb_max(a, b), c) +#endif + + +GB_MATH_DEF float gb_copy_sign (float x, float y); +GB_MATH_DEF float gb_remainder (float x, float y); +GB_MATH_DEF float gb_mod (float x, float y); +GB_MATH_DEF float gb_sqrt (float a); +GB_MATH_DEF float gb_rsqrt (float a); +GB_MATH_DEF float gb_quake_rsqrt(float a); /* NOTE(bill): It's probably better to use 1.0f/gb_sqrt(a) + * And for simd, there is usually isqrt functions too! + */ +GB_MATH_DEF float gb_sin (float radians); +GB_MATH_DEF float gb_cos (float radians); +GB_MATH_DEF float gb_tan (float radians); +GB_MATH_DEF float gb_arcsin (float a); +GB_MATH_DEF float gb_arccos (float a); +GB_MATH_DEF float gb_arctan (float a); +GB_MATH_DEF float gb_arctan2(float y, float x); + +GB_MATH_DEF float gb_exp (float x); +GB_MATH_DEF float gb_exp2 (float x); +GB_MATH_DEF float gb_log (float x); +GB_MATH_DEF float gb_log2 (float x); +GB_MATH_DEF float gb_fast_exp (float x); /* NOTE(bill): Only valid from -1 <= x <= +1 */ +GB_MATH_DEF float gb_fast_exp2(float x); /* NOTE(bill): Only valid from -1 <= x <= +1 */ +GB_MATH_DEF float gb_pow (float x, float y); /* x^y */ + +GB_MATH_DEF float gb_round(float x); +GB_MATH_DEF float gb_floor(float x); +GB_MATH_DEF float gb_ceil (float x); + +GB_MATH_DEF float gb_half_to_float(gbHalf value); +GB_MATH_DEF gbHalf gb_float_to_half(float value); + + +GB_MATH_DEF gbVec2 gb_vec2_zero(void); +GB_MATH_DEF gbVec2 gb_vec2 (float x, float y); +GB_MATH_DEF gbVec2 gb_vec2v (float x[2]); + +GB_MATH_DEF gbVec3 gb_vec3_zero(void); +GB_MATH_DEF gbVec3 gb_vec3 (float x, float y, float z); +GB_MATH_DEF gbVec3 gb_vec3v (float x[3]); + +GB_MATH_DEF gbVec4 gb_vec4_zero(void); +GB_MATH_DEF gbVec4 gb_vec4 (float x, float y, float z, float w); +GB_MATH_DEF gbVec4 gb_vec4v (float x[4]); + + +GB_MATH_DEF void gb_vec2_add(gbVec2 *d, gbVec2 v0, gbVec2 v1); +GB_MATH_DEF void gb_vec2_sub(gbVec2 *d, gbVec2 v0, gbVec2 v1); +GB_MATH_DEF void gb_vec2_mul(gbVec2 *d, gbVec2 v, float s); +GB_MATH_DEF void gb_vec2_div(gbVec2 *d, gbVec2 v, float s); + +GB_MATH_DEF void gb_vec3_add(gbVec3 *d, gbVec3 v0, gbVec3 v1); +GB_MATH_DEF void gb_vec3_sub(gbVec3 *d, gbVec3 v0, gbVec3 v1); +GB_MATH_DEF void gb_vec3_mul(gbVec3 *d, gbVec3 v, float s); +GB_MATH_DEF void gb_vec3_div(gbVec3 *d, gbVec3 v, float s); + +GB_MATH_DEF void gb_vec4_add(gbVec4 *d, gbVec4 v0, gbVec4 v1); +GB_MATH_DEF void gb_vec4_sub(gbVec4 *d, gbVec4 v0, gbVec4 v1); +GB_MATH_DEF void gb_vec4_mul(gbVec4 *d, gbVec4 v, float s); +GB_MATH_DEF void gb_vec4_div(gbVec4 *d, gbVec4 v, float s); + +GB_MATH_DEF void gb_vec2_addeq(gbVec2 *d, gbVec2 v); +GB_MATH_DEF void gb_vec2_subeq(gbVec2 *d, gbVec2 v); +GB_MATH_DEF void gb_vec2_muleq(gbVec2 *d, float s); +GB_MATH_DEF void gb_vec2_diveq(gbVec2 *d, float s); + +GB_MATH_DEF void gb_vec3_addeq(gbVec3 *d, gbVec3 v); +GB_MATH_DEF void gb_vec3_subeq(gbVec3 *d, gbVec3 v); +GB_MATH_DEF void gb_vec3_muleq(gbVec3 *d, float s); +GB_MATH_DEF void gb_vec3_diveq(gbVec3 *d, float s); + +GB_MATH_DEF void gb_vec4_addeq(gbVec4 *d, gbVec4 v); +GB_MATH_DEF void gb_vec4_subeq(gbVec4 *d, gbVec4 v); +GB_MATH_DEF void gb_vec4_muleq(gbVec4 *d, float s); +GB_MATH_DEF void gb_vec4_diveq(gbVec4 *d, float s); + +GB_MATH_DEF float gb_vec2_dot(gbVec2 v0, gbVec2 v1); +GB_MATH_DEF float gb_vec3_dot(gbVec3 v0, gbVec3 v1); +GB_MATH_DEF float gb_vec4_dot(gbVec4 v0, gbVec4 v1); + +GB_MATH_DEF void gb_vec2_cross(float *d, gbVec2 v0, gbVec2 v1); +GB_MATH_DEF void gb_vec3_cross(gbVec3 *d, gbVec3 v0, gbVec3 v1); + +GB_MATH_DEF float gb_vec2_mag2(gbVec2 v); +GB_MATH_DEF float gb_vec3_mag2(gbVec3 v); +GB_MATH_DEF float gb_vec4_mag2(gbVec4 v); + +GB_MATH_DEF float gb_vec2_mag(gbVec2 v); +GB_MATH_DEF float gb_vec3_mag(gbVec3 v); +GB_MATH_DEF float gb_vec4_mag(gbVec4 v); + +GB_MATH_DEF void gb_vec2_norm(gbVec2 *d, gbVec2 v); +GB_MATH_DEF void gb_vec3_norm(gbVec3 *d, gbVec3 v); +GB_MATH_DEF void gb_vec4_norm(gbVec4 *d, gbVec4 v); + +GB_MATH_DEF void gb_vec2_norm0(gbVec2 *d, gbVec2 v); +GB_MATH_DEF void gb_vec3_norm0(gbVec3 *d, gbVec3 v); +GB_MATH_DEF void gb_vec4_norm0(gbVec4 *d, gbVec4 v); + +GB_MATH_DEF void gb_vec2_reflect(gbVec2 *d, gbVec2 i, gbVec2 n); +GB_MATH_DEF void gb_vec3_reflect(gbVec3 *d, gbVec3 i, gbVec3 n); +GB_MATH_DEF void gb_vec2_refract(gbVec2 *d, gbVec2 i, gbVec2 n, float eta); +GB_MATH_DEF void gb_vec3_refract(gbVec3 *d, gbVec3 i, gbVec3 n, float eta); + +GB_MATH_DEF float gb_vec2_aspect_ratio(gbVec2 v); + + +GB_MATH_DEF void gb_mat2_identity (gbMat2 *m); +GB_MATH_DEF void gb_float22_identity(float m[2][2]); + +GB_MATH_DEF void gb_mat2_transpose (gbMat2 *m); +GB_MATH_DEF void gb_mat2_mul (gbMat2 *out, gbMat2 *m1, gbMat2 *m2); +GB_MATH_DEF void gb_mat2_mul_vec2 (gbVec2 *out, gbMat2 *m, gbVec2 in); +GB_MATH_DEF void gb_mat2_inverse (gbMat2 *out, gbMat2 *in); +GB_MATH_DEF float gb_mat2_determinate(gbMat2 *m); + +GB_MATH_DEF gbMat2 *gb_mat2_v(gbVec2 m[2]); +GB_MATH_DEF gbMat2 *gb_mat2_f(float m[2][2]); +GB_MATH_DEF gbFloat2 *gb_float22_m(gbMat2 *m); +GB_MATH_DEF gbFloat2 *gb_float22_v(gbVec2 m[2]); +GB_MATH_DEF gbFloat2 *gb_float22_4(float m[4]); + +GB_MATH_DEF void gb_float22_transpose(float (*vec)[2]); +GB_MATH_DEF void gb_float22_mul (float (*out)[2], float (*mat1)[2], float (*mat2)[2]); +GB_MATH_DEF void gb_float22_mul_vec2 (gbVec2 *out, float m[2][2], gbVec2 in); + + +GB_MATH_DEF void gb_mat3_identity (gbMat3 *m); +GB_MATH_DEF void gb_float33_identity(float m[3][3]); + +GB_MATH_DEF void gb_mat3_transpose (gbMat3 *m); +GB_MATH_DEF void gb_mat3_mul (gbMat3 *out, gbMat3 *m1, gbMat3 *m2); +GB_MATH_DEF void gb_mat3_mul_vec3 (gbVec3 *out, gbMat3 *m, gbVec3 in); +GB_MATH_DEF void gb_mat3_inverse (gbMat3 *out, gbMat3 *in); +GB_MATH_DEF float gb_mat3_determinate(gbMat3 *m); + + +GB_MATH_DEF gbMat3 *gb_mat3_v(gbVec3 m[3]); +GB_MATH_DEF gbMat3 *gb_mat3_f(float m[3][3]); + +GB_MATH_DEF gbFloat3 *gb_float33_m(gbMat3 *m); +GB_MATH_DEF gbFloat3 *gb_float33_v(gbVec3 m[3]); +GB_MATH_DEF gbFloat3 *gb_float33_9(float m[9]); + +GB_MATH_DEF void gb_float33_transpose(float (*vec)[3]); +GB_MATH_DEF void gb_float33_mul (float (*out)[3], float (*mat1)[3], float (*mat2)[3]); +GB_MATH_DEF void gb_float33_mul_vec3 (gbVec3 *out, float m[3][3], gbVec3 in); + +GB_MATH_DEF void gb_mat4_identity (gbMat4 *m); +GB_MATH_DEF void gb_float44_identity(float m[4][4]); + +GB_MATH_DEF void gb_mat4_transpose (gbMat4 *m); +GB_MATH_DEF void gb_mat4_mul (gbMat4 *out, gbMat4 *m1, gbMat4 *m2); +GB_MATH_DEF void gb_mat4_mul_vec4 (gbVec4 *out, gbMat4 *m, gbVec4 in); +GB_MATH_DEF void gb_mat4_inverse (gbMat4 *out, gbMat4 *in); + +GB_MATH_DEF gbMat4 *gb_mat4_v(gbVec4 m[4]); +GB_MATH_DEF gbMat4 *gb_mat4_f(float m[4][4]); + +GB_MATH_DEF gbFloat4 *gb_float44_m (gbMat4 *m); +GB_MATH_DEF gbFloat4 *gb_float44_v (gbVec4 m[4]); +GB_MATH_DEF gbFloat4 *gb_float44_16(float m[16]); + +GB_MATH_DEF void gb_float44_transpose(float (*vec)[4]); +GB_MATH_DEF void gb_float44_mul (float (*out)[4], float (*mat1)[4], float (*mat2)[4]); +GB_MATH_DEF void gb_float44_mul_vec4 (gbVec4 *out, float m[4][4], gbVec4 in); + + +GB_MATH_DEF void gb_mat4_translate (gbMat4 *out, gbVec3 v); +GB_MATH_DEF void gb_mat4_rotate (gbMat4 *out, gbVec3 v, float angle_radians); +GB_MATH_DEF void gb_mat4_scale (gbMat4 *out, gbVec3 v); +GB_MATH_DEF void gb_mat4_scalef (gbMat4 *out, float s); +GB_MATH_DEF void gb_mat4_ortho2d (gbMat4 *out, float left, float right, float bottom, float top); +GB_MATH_DEF void gb_mat4_ortho3d (gbMat4 *out, float left, float right, float bottom, float top, float z_near, float z_far); +GB_MATH_DEF void gb_mat4_perspective (gbMat4 *out, float fovy, float aspect, float z_near, float z_far); +GB_MATH_DEF void gb_mat4_infinite_perspective(gbMat4 *out, float fovy, float aspect, float z_near); + +GB_MATH_DEF void gb_mat4_look_at(gbMat4 *out, gbVec3 eye, gbVec3 centre, gbVec3 up); + + + +GB_MATH_DEF gbQuat gb_quat (float x, float y, float z, float w); +GB_MATH_DEF gbQuat gb_quatv (float e[4]); +GB_MATH_DEF gbQuat gb_quat_axis_angle (gbVec3 axis, float angle_radians); +GB_MATH_DEF gbQuat gb_quat_euler_angles(float pitch, float yaw, float roll); +GB_MATH_DEF gbQuat gb_quat_identity (void); + +GB_MATH_DEF void gb_quat_add(gbQuat *d, gbQuat q0, gbQuat q1); +GB_MATH_DEF void gb_quat_sub(gbQuat *d, gbQuat q0, gbQuat q1); +GB_MATH_DEF void gb_quat_mul(gbQuat *d, gbQuat q0, gbQuat q1); +GB_MATH_DEF void gb_quat_div(gbQuat *d, gbQuat q0, gbQuat q1); + +GB_MATH_DEF void gb_quat_mulf(gbQuat *d, gbQuat q, float s); +GB_MATH_DEF void gb_quat_divf(gbQuat *d, gbQuat q, float s); + + +GB_MATH_DEF void gb_quat_addeq(gbQuat *d, gbQuat q); +GB_MATH_DEF void gb_quat_subeq(gbQuat *d, gbQuat q); +GB_MATH_DEF void gb_quat_muleq(gbQuat *d, gbQuat q); +GB_MATH_DEF void gb_quat_diveq(gbQuat *d, gbQuat q); + + +GB_MATH_DEF void gb_quat_muleqf(gbQuat *d, float s); +GB_MATH_DEF void gb_quat_diveqf(gbQuat *d, float s); + + + + +GB_MATH_DEF float gb_quat_dot(gbQuat q0, gbQuat q1); +GB_MATH_DEF float gb_quat_mag(gbQuat q); + +GB_MATH_DEF void gb_quat_norm (gbQuat *d, gbQuat q); +GB_MATH_DEF void gb_quat_conj (gbQuat *d, gbQuat q); +GB_MATH_DEF void gb_quat_inverse(gbQuat *d, gbQuat q); + +GB_MATH_DEF void gb_quat_axis (gbVec3 *axis, gbQuat q); +GB_MATH_DEF float gb_quat_angle(gbQuat q); + +GB_MATH_DEF float gb_quat_pitch(gbQuat q); +GB_MATH_DEF float gb_quat_yaw (gbQuat q); +GB_MATH_DEF float gb_quat_roll (gbQuat q); + +/* NOTE(bill): Rotate v by q */ +GB_MATH_DEF void gb_quat_rotate_vec3(gbVec3 *d, gbQuat q, gbVec3 v); +GB_MATH_DEF void gb_mat4_from_quat (gbMat4 *out, gbQuat q); +GB_MATH_DEF void gb_quat_from_mat4 (gbQuat *out, gbMat4 *m); + + + +/* Interpolations */ +GB_MATH_DEF float gb_lerp (float a, float b, float t); +GB_MATH_DEF float gb_unlerp (float t, float a, float b); +GB_MATH_DEF float gb_smooth_step (float a, float b, float t); +GB_MATH_DEF float gb_smoother_step(float a, float b, float t); + +GB_MATH_DEF void gb_vec2_lerp(gbVec2 *d, gbVec2 a, gbVec2 b, float t); +GB_MATH_DEF void gb_vec3_lerp(gbVec3 *d, gbVec3 a, gbVec3 b, float t); +GB_MATH_DEF void gb_vec4_lerp(gbVec4 *d, gbVec4 a, gbVec4 b, float t); + +GB_MATH_DEF void gb_quat_lerp (gbQuat *d, gbQuat a, gbQuat b, float t); +GB_MATH_DEF void gb_quat_nlerp(gbQuat *d, gbQuat a, gbQuat b, float t); +GB_MATH_DEF void gb_quat_slerp(gbQuat *d, gbQuat a, gbQuat b, float t); +GB_MATH_DEF void gb_quat_nquad(gbQuat *d, gbQuat p, gbQuat a, gbQuat b, gbQuat q, float t); +GB_MATH_DEF void gb_quat_squad(gbQuat *d, gbQuat p, gbQuat a, gbQuat b, gbQuat q, float t); +GB_MATH_DEF void gb_quat_slerp_approx(gbQuat *d, gbQuat a, gbQuat b, float t); +GB_MATH_DEF void gb_quat_squad_approx(gbQuat *d, gbQuat p, gbQuat a, gbQuat b, gbQuat q, float t); + + +/* Rects */ +GB_MATH_DEF gbRect2 gb_rect2(gbVec2 pos, gbVec2 dim); +GB_MATH_DEF gbRect2 gb_rect2v(float v[4]); + +GB_MATH_DEF gbRect3 gb_rect3(gbVec3 pos, gbVec3 dim); +GB_MATH_DEF gbRect3 gb_rect3v(float v[6]); + +GB_MATH_DEF int gb_rect2_contains (gbRect2 a, float x, float y); +GB_MATH_DEF int gb_rect2_contains_vec2 (gbRect2 a, gbVec2 p); +GB_MATH_DEF int gb_rect2_intersects (gbRect2 a, gbRect2 b); +GB_MATH_DEF int gb_rect2_intersection_result(gbRect2 a, gbRect2 b, gbRect2 *intersection); + + +#ifndef GB_MURMUR64_DEFAULT_SEED +#define GB_MURMUR64_DEFAULT_SEED 0x9747b28c +#endif +/* Hashing */ +GB_MATH_DEF gb_math_u64 gb_hash_murmur64(void const *key, size_t num_bytes, gb_math_u64 seed); + +/* Random */ +/* TODO(bill): Use a generator for the random numbers */ +GB_MATH_DEF float gb_random_range_float(float min_inc, float max_inc); +GB_MATH_DEF int gb_random_range_int (int min_inc, int max_inc); +GB_MATH_DEF float gb_random01 (void); + + + +#if defined(__cplusplus) +} +#endif + +#if defined(__cplusplus) + +/* TODO(bill): How should I apply GB_MATH_DEF to these operator overloads? */ + +inline bool operator==(gbVec2 a, gbVec2 b) { return (a.x == b.x) && (a.y == b.y); } +inline bool operator!=(gbVec2 a, gbVec2 b) { return !operator==(a, b); } + +inline gbVec2 operator+(gbVec2 a) { return a; } +inline gbVec2 operator-(gbVec2 a) { gbVec2 r = {-a.x, -a.y}; return r; } + +inline gbVec2 operator+(gbVec2 a, gbVec2 b) { gbVec2 r; gb_vec2_add(&r, a, b); return r; } +inline gbVec2 operator-(gbVec2 a, gbVec2 b) { gbVec2 r; gb_vec2_sub(&r, a, b); return r; } + +inline gbVec2 operator*(gbVec2 a, float scalar) { gbVec2 r; gb_vec2_mul(&r, a, scalar); return r; } +inline gbVec2 operator*(float scalar, gbVec2 a) { return operator*(a, scalar); } + +inline gbVec2 operator/(gbVec2 a, float scalar) { return operator*(a, 1.0f/scalar); } + +/* Hadamard Product */ +inline gbVec2 operator*(gbVec2 a, gbVec2 b) { gbVec2 r = {a.x*b.x, a.y*b.y}; return r; } +inline gbVec2 operator/(gbVec2 a, gbVec2 b) { gbVec2 r = {a.x/b.x, a.y/b.y}; return r; } + +inline gbVec2 &operator+=(gbVec2 &a, gbVec2 b) { return (a = a + b); } +inline gbVec2 &operator-=(gbVec2 &a, gbVec2 b) { return (a = a - b); } +inline gbVec2 &operator*=(gbVec2 &a, float scalar) { return (a = a * scalar); } +inline gbVec2 &operator/=(gbVec2 &a, float scalar) { return (a = a / scalar); } + + +inline bool operator==(gbVec3 a, gbVec3 b) { return (a.x == b.x) && (a.y == b.y) && (a.z == b.z); } +inline bool operator!=(gbVec3 a, gbVec3 b) { return !operator==(a, b); } + +inline gbVec3 operator+(gbVec3 a) { return a; } +inline gbVec3 operator-(gbVec3 a) { gbVec3 r = {-a.x, -a.y, -a.z}; return r; } + +inline gbVec3 operator+(gbVec3 a, gbVec3 b) { gbVec3 r; gb_vec3_add(&r, a, b); return r; } +inline gbVec3 operator-(gbVec3 a, gbVec3 b) { gbVec3 r; gb_vec3_sub(&r, a, b); return r; } + +inline gbVec3 operator*(gbVec3 a, float scalar) { gbVec3 r; gb_vec3_mul(&r, a, scalar); return r; } +inline gbVec3 operator*(float scalar, gbVec3 a) { return operator*(a, scalar); } + +inline gbVec3 operator/(gbVec3 a, float scalar) { return operator*(a, 1.0f/scalar); } + +/* Hadamard Product */ +inline gbVec3 operator*(gbVec3 a, gbVec3 b) { gbVec3 r = {a.x*b.x, a.y*b.y, a.z*b.z}; return r; } +inline gbVec3 operator/(gbVec3 a, gbVec3 b) { gbVec3 r = {a.x/b.x, a.y/b.y, a.z/b.z}; return r; } + +inline gbVec3 &operator+=(gbVec3 &a, gbVec3 b) { return (a = a + b); } +inline gbVec3 &operator-=(gbVec3 &a, gbVec3 b) { return (a = a - b); } +inline gbVec3 &operator*=(gbVec3 &a, float scalar) { return (a = a * scalar); } +inline gbVec3 &operator/=(gbVec3 &a, float scalar) { return (a = a / scalar); } + + +inline bool operator==(gbVec4 a, gbVec4 b) { return (a.x == b.x) && (a.y == b.y) && (a.z == b.z) && (a.w == b.w); } +inline bool operator!=(gbVec4 a, gbVec4 b) { return !operator==(a, b); } + +inline gbVec4 operator+(gbVec4 a) { return a; } +inline gbVec4 operator-(gbVec4 a) { gbVec4 r = {-a.x, -a.y, -a.z, -a.w}; return r; } + +inline gbVec4 operator+(gbVec4 a, gbVec4 b) { gbVec4 r; gb_vec4_add(&r, a, b); return r; } +inline gbVec4 operator-(gbVec4 a, gbVec4 b) { gbVec4 r; gb_vec4_sub(&r, a, b); return r; } + +inline gbVec4 operator*(gbVec4 a, float scalar) { gbVec4 r; gb_vec4_mul(&r, a, scalar); return r; } +inline gbVec4 operator*(float scalar, gbVec4 a) { return operator*(a, scalar); } + +inline gbVec4 operator/(gbVec4 a, float scalar) { return operator*(a, 1.0f/scalar); } + +/* Hadamard Product */ +inline gbVec4 operator*(gbVec4 a, gbVec4 b) { gbVec4 r = {a.x*b.x, a.y*b.y, a.z*b.z, a.w*b.w}; return r; } +inline gbVec4 operator/(gbVec4 a, gbVec4 b) { gbVec4 r = {a.x/b.x, a.y/b.y, a.z/b.z, a.w/b.w}; return r; } + +inline gbVec4 &operator+=(gbVec4 &a, gbVec4 b) { return (a = a + b); } +inline gbVec4 &operator-=(gbVec4 &a, gbVec4 b) { return (a = a - b); } +inline gbVec4 &operator*=(gbVec4 &a, float scalar) { return (a = a * scalar); } +inline gbVec4 &operator/=(gbVec4 &a, float scalar) { return (a = a / scalar); } + + +inline gbMat2 operator+(gbMat2 const &a, gbMat2 const &b) { + int i, j; + gbMat2 r = {0}; + for (j = 0; j < 2; j++) { + for (i = 0; i < 2; i++) + r.e[2*j+i] = a.e[2*j+i] + b.e[2*j+i]; + } + return r; +} + +inline gbMat2 operator-(gbMat2 const &a, gbMat2 const &b) { + int i, j; + gbMat2 r = {0}; + for (j = 0; j < 2; j++) { + for (i = 0; i < 2; i++) + r.e[2*j+i] = a.e[2*j+i] - b.e[2*j+i]; + } + return r; +} + +inline gbMat2 operator*(gbMat2 const &a, gbMat2 const &b) { gbMat2 r; gb_mat2_mul(&r, (gbMat2 *)&a, (gbMat2 *)&b); return r; } +inline gbVec2 operator*(gbMat2 const &a, gbVec2 v) { gbVec2 r; gb_mat2_mul_vec2(&r, (gbMat2 *)&a, v); return r; } +inline gbMat2 operator*(gbMat2 const &a, float scalar) { + gbMat2 r = {0}; + int i; + for (i = 0; i < 2*2; i++) r.e[i] = a.e[i] * scalar; + return r; +} +inline gbMat2 operator*(float scalar, gbMat2 const &a) { return operator*(a, scalar); } +inline gbMat2 operator/(gbMat2 const &a, float scalar) { return operator*(a, 1.0f/scalar); } + +inline gbMat2& operator+=(gbMat2& a, gbMat2 const &b) { return (a = a + b); } +inline gbMat2& operator-=(gbMat2& a, gbMat2 const &b) { return (a = a - b); } +inline gbMat2& operator*=(gbMat2& a, gbMat2 const &b) { return (a = a * b); } + + + +inline gbMat3 operator+(gbMat3 const &a, gbMat3 const &b) { + int i, j; + gbMat3 r = {0}; + for (j = 0; j < 3; j++) { + for (i = 0; i < 3; i++) + r.e[3*j+i] = a.e[3*j+i] + b.e[3*j+i]; + } + return r; +} + +inline gbMat3 operator-(gbMat3 const &a, gbMat3 const &b) { + int i, j; + gbMat3 r = {0}; + for (j = 0; j < 3; j++) { + for (i = 0; i < 3; i++) + r.e[3*j+i] = a.e[3*j+i] - b.e[3*j+i]; + } + return r; +} + +inline gbMat3 operator*(gbMat3 const &a, gbMat3 const &b) { gbMat3 r; gb_mat3_mul(&r, (gbMat3 *)&a, (gbMat3 *)&b); return r; } +inline gbVec3 operator*(gbMat3 const &a, gbVec3 v) { gbVec3 r; gb_mat3_mul_vec3(&r, (gbMat3 *)&a, v); return r; } inline gbMat3 operator*(gbMat3 const &a, float scalar) { + gbMat3 r = {0}; + int i; + for (i = 0; i < 3*3; i++) r.e[i] = a.e[i] * scalar; + return r; +} +inline gbMat3 operator*(float scalar, gbMat3 const &a) { return operator*(a, scalar); } +inline gbMat3 operator/(gbMat3 const &a, float scalar) { return operator*(a, 1.0f/scalar); } + +inline gbMat3& operator+=(gbMat3& a, gbMat3 const &b) { return (a = a + b); } +inline gbMat3& operator-=(gbMat3& a, gbMat3 const &b) { return (a = a - b); } +inline gbMat3& operator*=(gbMat3& a, gbMat3 const &b) { return (a = a * b); } + + + +inline gbMat4 operator+(gbMat4 const &a, gbMat4 const &b) { + int i, j; + gbMat4 r = {0}; + for (j = 0; j < 4; j++) { + for (i = 0; i < 4; i++) + r.e[4*j+i] = a.e[4*j+i] + b.e[4*j+i]; + } + return r; +} + +inline gbMat4 operator-(gbMat4 const &a, gbMat4 const &b) { + int i, j; + gbMat4 r = {0}; + for (j = 0; j < 4; j++) { + for (i = 0; i < 4; i++) + r.e[4*j+i] = a.e[4*j+i] - b.e[4*j+i]; + } + return r; +} + +inline gbMat4 operator*(gbMat4 const &a, gbMat4 const &b) { gbMat4 r; gb_mat4_mul(&r, (gbMat4 *)&a, (gbMat4 *)&b); return r; } +inline gbVec4 operator*(gbMat4 const &a, gbVec4 v) { gbVec4 r; gb_mat4_mul_vec4(&r, (gbMat4 *)&a, v); return r; } +inline gbMat4 operator*(gbMat4 const &a, float scalar) { + gbMat4 r = {0}; + int i; + for (i = 0; i < 4*4; i++) r.e[i] = a.e[i] * scalar; + return r; +} +inline gbMat4 operator*(float scalar, gbMat4 const &a) { return operator*(a, scalar); } +inline gbMat4 operator/(gbMat4 const &a, float scalar) { return operator*(a, 1.0f/scalar); } + +inline gbMat4& operator+=(gbMat4 &a, gbMat4 const &b) { return (a = a + b); } +inline gbMat4& operator-=(gbMat4 &a, gbMat4 const &b) { return (a = a - b); } +inline gbMat4& operator*=(gbMat4 &a, gbMat4 const &b) { return (a = a * b); } + + + +inline bool operator==(gbQuat a, gbQuat b) { return a.xyzw == b.xyzw; } +inline bool operator!=(gbQuat a, gbQuat b) { return !operator==(a, b); } + +inline gbQuat operator+(gbQuat q) { return q; } +inline gbQuat operator-(gbQuat q) { return gb_quat(-q.x, -q.y, -q.z, -q.w); } + +inline gbQuat operator+(gbQuat a, gbQuat b) { gbQuat r; gb_quat_add(&r, a, b); return r; } +inline gbQuat operator-(gbQuat a, gbQuat b) { gbQuat r; gb_quat_sub(&r, a, b); return r; } + +inline gbQuat operator*(gbQuat a, gbQuat b) { gbQuat r; gb_quat_mul(&r, a, b); return r; } +inline gbQuat operator*(gbQuat q, float s) { gbQuat r; gb_quat_mulf(&r, q, s); return r; } +inline gbQuat operator*(float s, gbQuat q) { return operator*(q, s); } +inline gbQuat operator/(gbQuat q, float s) { gbQuat r; gb_quat_divf(&r, q, s); return r; } + +inline gbQuat &operator+=(gbQuat &a, gbQuat b) { gb_quat_addeq(&a, b); return a; } +inline gbQuat &operator-=(gbQuat &a, gbQuat b) { gb_quat_subeq(&a, b); return a; } +inline gbQuat &operator*=(gbQuat &a, gbQuat b) { gb_quat_muleq(&a, b); return a; } +inline gbQuat &operator/=(gbQuat &a, gbQuat b) { gb_quat_diveq(&a, b); return a; } + +inline gbQuat &operator*=(gbQuat &a, float b) { gb_quat_muleqf(&a, b); return a; } +inline gbQuat &operator/=(gbQuat &a, float b) { gb_quat_diveqf(&a, b); return a; } + +/* Rotate v by a */ +inline gbVec3 operator*(gbQuat q, gbVec3 v) { gbVec3 r; gb_quat_rotate_vec3(&r, q, v); return r; } + +#endif + + + + +#endif /* GB_MATH_INCLUDE_GB_MATH_H */ + +/**************************************************************** + * + * + * + * + * + * + * + * + * + * + * + * + * + * + * + * + * + * Implementation + * + * + * + * + * + * + * + * + * + * + * + * + * + * + * + * + ****************************************************************/ + +#if defined(GB_MATH_IMPLEMENTATION) && !defined(GB_MATH_IMPLEMENTATION_DONE) +#define GB_MATH_IMPLEMENTATION_DONE + + #if (defined(__GCC__) || defined(__GNUC__)) && !defined(__clang__) + #pragma GCC diagnostic push + #pragma GCC diagnostic ignored "-Wattributes" + #pragma GCC diagnostic ignored "-Wmissing-braces" + #elif __clang__ + #pragma clang diagnostic push + #pragma clang diagnostic ignored "-Wattributes" + #pragma clang diagnostic ignored "-Wmissing-braces" + #endif + + +/* NOTE(bill): To remove the need for memcpy */ +static void gb__memcpy_4byte(void *dest, void const *src, size_t size) { + size_t i; + unsigned int *d, *s; + d = (unsigned int *)dest; + s = (unsigned int *)src; + for (i = 0; i < size/4; i++) { + *d++ = *s++; + } +} + + +float gb_to_radians(float degrees) { return degrees * GB_MATH_TAU / 360.0f; } +float gb_to_degrees(float radians) { return radians * 360.0f / GB_MATH_TAU; } + +float gb_angle_diff(float radians_a, float radians_b) { + float delta = gb_mod(radians_b-radians_a, GB_MATH_TAU); + delta = gb_mod(delta + 1.5f*GB_MATH_TAU, GB_MATH_TAU); + delta -= 0.5f*GB_MATH_TAU; + return delta; +} + +float gb_copy_sign(float x, float y) { + int ix, iy; + ix = *(int *)&x; + iy = *(int *)&y; + + ix &= 0x7fffffff; + ix |= iy & 0x80000000; + return *(float *)&ix; +} + +float gb_remainder(float x, float y) { + return x - (gb_round(x/y)*y); +} + +float gb_mod(float x, float y) { + float result; + y = gb_abs(y); + result = gb_remainder(gb_abs(x), y); + if (gb_sign(result)) result += y; + return gb_copy_sign(result, x); +} + + +float gb_quake_rsqrt(float a) { + union { + int i; + float f; + } t; + float x2; + float const three_halfs = 1.5f; + + x2 = a * 0.5f; + t.f = a; + t.i = 0x5f375a86 - (t.i >> 1); /* What the fuck? */ + t.f = t.f * (three_halfs - (x2 * t.f * t.f)); /* 1st iteration */ + t.f = t.f * (three_halfs - (x2 * t.f * t.f)); /* 2nd iteration, this can be removed */ + + return t.f; +} + + +#if defined(GB_MATH_NO_MATH_H) +#if defined(_MSC_VER) + + float gb_rsqrt(float a) { return _mm_cvtss_f32(_mm_rsqrt_ss(_mm_set_ss(a))); } + float gb_sqrt(float a) { return _mm_cvtss_f32(_mm_sqrt_ss(_mm_set_ss(a))); }; + float + gb_sin(float a) + { + static float const a0 = +1.91059300966915117e-31f; + static float const a1 = +1.00086760103908896f; + static float const a2 = -1.21276126894734565e-2f; + static float const a3 = -1.38078780785773762e-1f; + static float const a4 = -2.67353392911981221e-2f; + static float const a5 = +2.08026600266304389e-2f; + static float const a6 = -3.03996055049204407e-3f; + static float const a7 = +1.38235642404333740e-4f; + return a0 + a*(a1 + a*(a2 + a*(a3 + a*(a4 + a*(a5 + a*(a6 + a*a7)))))); + } + float + gb_cos(float a) + { + static float const a0 = +1.00238601909309722f; + static float const a1 = -3.81919947353040024e-2f; + static float const a2 = -3.94382342128062756e-1f; + static float const a3 = -1.18134036025221444e-1f; + static float const a4 = +1.07123798512170878e-1f; + static float const a5 = -1.86637164165180873e-2f; + static float const a6 = +9.90140908664079833e-4f; + static float const a7 = -5.23022132118824778e-14f; + return a0 + a*(a1 + a*(a2 + a*(a3 + a*(a4 + a*(a5 + a*(a6 + a*a7)))))); + } + + float + gb_tan(float radians) + { + float rr = radians*radians; + float a = 9.5168091e-03f; + a *= rr; + a += 2.900525e-03f; + a *= rr; + a += 2.45650893e-02f; + a *= rr; + a += 5.33740603e-02f; + a *= rr; + a += 1.333923995e-01f; + a *= rr; + a += 3.333314036e-01f; + a *= rr; + a += 1.0f; + a *= radians; + return a; + } + + float gb_arcsin(float a) { return gb_arctan2(a, gb_sqrt((1.0f + a) * (1.0f - a))); } + float gb_arccos(float a) { return gb_arctan2(gb_sqrt((1.0f + a) * (1.0 - a)), a); } + + float + gb_arctan(float a) + { + float u = a*a; + float u2 = u*u; + float u3 = u2*u; + float u4 = u3*u; + float f = 1.0f+0.33288950512027f*u-0.08467922817644f*u2+0.03252232640125f*u3-0.00749305860992f*u4; + return a/f; + } + + float + gb_arctan2(float y, float x) + { + if (gb_abs(x) > gb_abs(y)) { + float a = gb_arctan(y/x); + if (x > 0.0f) + return a; + else + return y > 0.0f ? a+GB_MATH_TAU_OVER_2:a-GB_MATH_TAU_OVER_2; + } else { + float a = gb_arctan(x/y); + if (x > 0.0f) + return y > 0.0f ? GB_MATH_TAU_OVER_4-a:-GB_MATH_TAU_OVER_4-a; + else + return y > 0.0f ? GB_MATH_TAU_OVER_4+a:-GB_MATH_TAU_OVER_4+a; + } + } + + float + gb_exp(float a) + { + union { float f; int i; } u, v; + u.i = (int)(6051102 * a + 1056478197); + v.i = (int)(1056478197 - 6051102 * a); + return u.f / v.f; + } + + float + gb_log(float a) + { + union { float f; int i; } u = {a}; + return (u.i - 1064866805) * 8.262958405176314e-8f; /* 1 / 12102203.0; */ + } + + float + gb_pow(float a, float b) + { + int flipped = 0, e; + float f, r = 1.0f; + if (b < 0) { + flipped = 1; + b = -b; + } + + e = (int)b; + f = gb_exp(b - e); + + while (e) { + if (e & 1) r *= a; + a *= a; + e >>= 1; + } + + r *= f; + return flipped ? 1.0f/r : r; + } + +#else + + float gb_rsqrt(float a) { return 1.0f/__builtin_sqrt(a); } + float gb_sqrt(float a) { return __builtin_sqrt(a); } + float gb_sin(float radians) { return __builtin_sinf(radians); } + float gb_cos(float radians) { return __builtin_cosf(radians); } + float gb_tan(float radians) { return __builtin_tanf(radians); } + float gb_arcsin(float a) { return __builtin_asinf(a); } + float gb_arccos(float a) { return __builtin_acosf(a); } + float gb_arctan(float a) { return __builtin_atanf(a); } + float gb_arctan2(float y, float x) { return __builtin_atan2f(y, x); } + + + float gb_exp(float x) { return __builtin_expf(x); } + float gb_log(float x) { return __builtin_logf(x); } + + // TODO(bill): Should this be gb_exp(y * gb_log(x)) ??? + float gb_pow(float x, float y) { return __builtin_powf(x, y); } + +#endif + +#else + float gb_rsqrt(float a) { return 1.0f/sqrtf(a); } + float gb_sqrt(float a) { return sqrtf(a); }; + float gb_sin(float radians) { return sinf(radians); }; + float gb_cos(float radians) { return cosf(radians); }; + float gb_tan(float radians) { return tanf(radians); }; + float gb_arcsin(float a) { return asinf(a); }; + float gb_arccos(float a) { return acosf(a); }; + float gb_arctan(float a) { return atanf(a); }; + float gb_arctan2(float y, float x) { return atan2f(y, x); }; + + float gb_exp(float x) { return expf(x); } + float gb_log(float x) { return logf(x); } + float gb_pow(float x, float y) { return powf(x, y); } +#endif + +float gb_exp2(float x) { return gb_exp(GB_MATH_LOG_TWO * x); } +float gb_log2(float x) { return gb_log(x) / GB_MATH_LOG_TWO; } + + +float gb_fast_exp(float x) { + /* NOTE(bill): Only works in the range -1 <= x <= +1 */ + float e = 1.0f + x*(1.0f + x*0.5f*(1.0f + x*0.3333333333f*(1.0f + x*0.25f*(1.0f + x*0.2f)))); + return e; +} + +float gb_fast_exp2(float x) { return gb_fast_exp(GB_MATH_LOG_TWO * x); } + + + +float gb_round(float x) { return (float)((x >= 0.0f) ? gb_floor(x + 0.5f) : gb_ceil(x - 0.5f)); } +float gb_floor(float x) { return (float)((x >= 0.0f) ? (int)x : (int)(x-0.9999999999999999f)); } +float gb_ceil(float x) { return (float)((x < 0) ? (int)x : ((int)x)+1); } + + + + + +float gb_half_to_float(gbHalf value) { + union { unsigned int i; float f; } result; + int s = (value >> 15) & 0x001; + int e = (value >> 10) & 0x01f; + int m = value & 0x3ff; + + if (e == 0) { + if (m == 0) { + /* Plus or minus zero */ + result.i = (unsigned int)(s << 31); + return result.f; + } else { + /* Denormalized number */ + while (!(m & 0x00000400)) { + m <<= 1; + e -= 1; + } + + e += 1; + m &= ~0x00000400; + } + } else if (e == 31) { + if (m == 0) { + /* Positive or negative infinity */ + result.i = (unsigned int)((s << 31) | 0x7f800000); + return result.f; + } else { + /* Nan */ + result.i = (unsigned int)((s << 31) | 0x7f800000 | (m << 13)); + return result.f; + } + } + + e = e + (127 - 15); + m = m << 13; + + result.i = (unsigned int)((s << 31) | (e << 23) | m); + return result.f; +} + +gbHalf gb_float_to_half(float value) { + union { unsigned int i; float f; } v; + int i, s, e, m; + + v.f = value; + i = (int)v.i; + + s = (i >> 16) & 0x00008000; + e = ((i >> 23) & 0x000000ff) - (127 - 15); + m = i & 0x007fffff; + + + if (e <= 0) { + if (e < -10) return (gbHalf)s; + m = (m | 0x00800000) >> (1 - e); + + if (m & 0x00001000) + m += 0x00002000; + + return (gbHalf)(s | (m >> 13)); + } else if (e == 0xff - (127 - 15)) { + if (m == 0) { + return (gbHalf)(s | 0x7c00); /* NOTE(bill): infinity */ + } else { + /* NOTE(bill): NAN */ + m >>= 13; + return (gbHalf)(s | 0x7c00 | m | (m == 0)); + } + } else { + if (m & 0x00001000) { + m += 0x00002000; + if (m & 0x00800000) { + m = 0; + e += 1; + } + } + + if (e > 30) { + float volatile f = 1e12f; + int j; + for (j = 0; j < 10; j++) + f *= f; /* NOTE(bill): Cause overflow */ + + return (gbHalf)(s | 0x7c00); + } + + return (gbHalf)(s | (e << 10) | (m >> 13)); + } +} + + + + + + + +#define GB_VEC2_2OP(a,c,post) \ + a->x = c.x post; \ + a->y = c.y post; + +#define GB_VEC2_3OP(a,b,op,c,post) \ + a->x = b.x op c.x post; \ + a->y = b.y op c.y post; + +#define GB_VEC3_2OP(a,c,post) \ + a->x = c.x post; \ + a->y = c.y post; \ + a->z = c.z post; + +#define GB_VEC3_3OP(a,b,op,c,post) \ + a->x = b.x op c.x post; \ + a->y = b.y op c.y post; \ + a->z = b.z op c.z post; + +#define GB_VEC4_2OP(a,c,post) \ + a->x = c.x post; \ + a->y = c.y post; \ + a->z = c.z post; \ + a->w = c.w post; + +#define GB_VEC4_3OP(a,b,op,c,post) \ + a->x = b.x op c.x post; \ + a->y = b.y op c.y post; \ + a->z = b.z op c.z post; \ + a->w = b.w op c.w post; + + +gbVec2 gb_vec2_zero(void) { gbVec2 v = {0, 0}; return v; } +gbVec2 gb_vec2(float x, float y) { gbVec2 v; v.x = x; v.y = y; return v; } +gbVec2 gb_vec2v(float x[2]) { gbVec2 v; v.x = x[0]; v.y = x[1]; return v; } + +gbVec3 gb_vec3_zero(void) { gbVec3 v = {0, 0, 0}; return v; } +gbVec3 gb_vec3(float x, float y, float z) { gbVec3 v; v.x = x; v.y = y; v.z = z; return v; } +gbVec3 gb_vec3v(float x[3]) { gbVec3 v; v.x = x[0]; v.y = x[1]; v.z = x[2]; return v; } + +gbVec4 gb_vec4_zero(void) { gbVec4 v = {0, 0, 0, 0}; return v; } +gbVec4 gb_vec4(float x, float y, float z, float w) { gbVec4 v; v.x = x; v.y = y; v.z = z; v.w = w; return v; } +gbVec4 gb_vec4v(float x[4]) { gbVec4 v; v.x = x[0]; v.y = x[1]; v.z = x[2]; v.w = x[3]; return v; } + + +void gb_vec2_add(gbVec2 *d, gbVec2 v0, gbVec2 v1) { GB_VEC2_3OP(d,v0,+,v1,+0); } +void gb_vec2_sub(gbVec2 *d, gbVec2 v0, gbVec2 v1) { GB_VEC2_3OP(d,v0,-,v1,+0); } +void gb_vec2_mul(gbVec2 *d, gbVec2 v, float s) { GB_VEC2_2OP(d,v,* s); } +void gb_vec2_div(gbVec2 *d, gbVec2 v, float s) { GB_VEC2_2OP(d,v,/ s); } + +void gb_vec3_add(gbVec3 *d, gbVec3 v0, gbVec3 v1) { GB_VEC3_3OP(d,v0,+,v1,+0); } +void gb_vec3_sub(gbVec3 *d, gbVec3 v0, gbVec3 v1) { GB_VEC3_3OP(d,v0,-,v1,+0); } +void gb_vec3_mul(gbVec3 *d, gbVec3 v, float s) { GB_VEC3_2OP(d,v,* s); } +void gb_vec3_div(gbVec3 *d, gbVec3 v, float s) { GB_VEC3_2OP(d,v,/ s); } + +void gb_vec4_add(gbVec4 *d, gbVec4 v0, gbVec4 v1) { GB_VEC4_3OP(d,v0,+,v1,+0); } +void gb_vec4_sub(gbVec4 *d, gbVec4 v0, gbVec4 v1) { GB_VEC4_3OP(d,v0,-,v1,+0); } +void gb_vec4_mul(gbVec4 *d, gbVec4 v, float s) { GB_VEC4_2OP(d,v,* s); } +void gb_vec4_div(gbVec4 *d, gbVec4 v, float s) { GB_VEC4_2OP(d,v,/ s); } + + +void gb_vec2_addeq(gbVec2 *d, gbVec2 v) { GB_VEC2_3OP(d,(*d),+,v,+0); } +void gb_vec2_subeq(gbVec2 *d, gbVec2 v) { GB_VEC2_3OP(d,(*d),-,v,+0); } +void gb_vec2_muleq(gbVec2 *d, float s) { GB_VEC2_2OP(d,(*d),* s); } +void gb_vec2_diveq(gbVec2 *d, float s) { GB_VEC2_2OP(d,(*d),/ s); } + +void gb_vec3_addeq(gbVec3 *d, gbVec3 v) { GB_VEC3_3OP(d,(*d),+,v,+0); } +void gb_vec3_subeq(gbVec3 *d, gbVec3 v) { GB_VEC3_3OP(d,(*d),-,v,+0); } +void gb_vec3_muleq(gbVec3 *d, float s) { GB_VEC3_2OP(d,(*d),* s); } +void gb_vec3_diveq(gbVec3 *d, float s) { GB_VEC3_2OP(d,(*d),/ s); } + +void gb_vec4_addeq(gbVec4 *d, gbVec4 v) { GB_VEC4_3OP(d,(*d),+,v,+0); } +void gb_vec4_subeq(gbVec4 *d, gbVec4 v) { GB_VEC4_3OP(d,(*d),-,v,+0); } +void gb_vec4_muleq(gbVec4 *d, float s) { GB_VEC4_2OP(d,(*d),* s); } +void gb_vec4_diveq(gbVec4 *d, float s) { GB_VEC4_2OP(d,(*d),/ s); } + + +#undef GB_VEC2_2OP +#undef GB_VEC2_3OP +#undef GB_VEC3_3OP +#undef GB_VEC3_2OP +#undef GB_VEC4_2OP +#undef GB_VEC4_3OP + + + + +float gb_vec2_dot(gbVec2 v0, gbVec2 v1) { return v0.x*v1.x + v0.y*v1.y; } +float gb_vec3_dot(gbVec3 v0, gbVec3 v1) { return v0.x*v1.x + v0.y*v1.y + v0.z*v1.z; } +float gb_vec4_dot(gbVec4 v0, gbVec4 v1) { return v0.x*v1.x + v0.y*v1.y + v0.z*v1.z + v0.w*v1.w; } + +void gb_vec2_cross(float *d, gbVec2 v0, gbVec2 v1) { *d = v0.x*v1.y - v1.x*v0.y; } +void gb_vec3_cross(gbVec3 *d, gbVec3 v0, gbVec3 v1) { d->x = v0.y*v1.z - v0.z*v1.y; + d->y = v0.z*v1.x - v0.x*v1.z; + d->z = v0.x*v1.y - v0.y*v1.x; } + +float gb_vec2_mag2(gbVec2 v) { return gb_vec2_dot(v, v); } +float gb_vec3_mag2(gbVec3 v) { return gb_vec3_dot(v, v); } +float gb_vec4_mag2(gbVec4 v) { return gb_vec4_dot(v, v); } + +/* TODO(bill): Create custom sqrt function */ +float gb_vec2_mag(gbVec2 v) { return gb_sqrt(gb_vec2_dot(v, v)); } +float gb_vec3_mag(gbVec3 v) { return gb_sqrt(gb_vec3_dot(v, v)); } +float gb_vec4_mag(gbVec4 v) { return gb_sqrt(gb_vec4_dot(v, v)); } + +void gb_vec2_norm(gbVec2 *d, gbVec2 v) { + float inv_mag = gb_rsqrt(gb_vec2_dot(v, v)); + gb_vec2_mul(d, v, inv_mag); +} +void gb_vec3_norm(gbVec3 *d, gbVec3 v) { + float mag = gb_vec3_mag(v); + gb_vec3_div(d, v, mag); +} +void gb_vec4_norm(gbVec4 *d, gbVec4 v) { + float mag = gb_vec4_mag(v); + gb_vec4_div(d, v, mag); +} + +void gb_vec2_norm0(gbVec2 *d, gbVec2 v) { + float mag = gb_vec2_mag(v); + if (mag > 0) + gb_vec2_div(d, v, mag); + else + *d = gb_vec2_zero(); +} +void gb_vec3_norm0(gbVec3 *d, gbVec3 v) { + float mag = gb_vec3_mag(v); + if (mag > 0) + gb_vec3_div(d, v, mag); + else + *d = gb_vec3_zero(); +} +void gb_vec4_norm0(gbVec4 *d, gbVec4 v) { + float mag = gb_vec4_mag(v); + if (mag > 0) + gb_vec4_div(d, v, mag); + else + *d = gb_vec4_zero(); +} + + +void gb_vec2_reflect(gbVec2 *d, gbVec2 i, gbVec2 n) { + gbVec2 b = n; + gb_vec2_muleq(&b, 2.0f*gb_vec2_dot(n, i)); + gb_vec2_sub(d, i, b); +} + +void gb_vec3_reflect(gbVec3 *d, gbVec3 i, gbVec3 n) { + gbVec3 b = n; + gb_vec3_muleq(&b, 2.0f*gb_vec3_dot(n, i)); + gb_vec3_sub(d, i, b); +} + +void gb_vec2_refract(gbVec2 *d, gbVec2 i, gbVec2 n, float eta) { + gbVec2 a, b; + float dv, k; + + dv = gb_vec2_dot(n, i); + k = 1.0f - eta*eta * (1.0f - dv*dv); + gb_vec2_mul(&a, i, eta); + gb_vec2_mul(&b, n, eta*dv*gb_sqrt(k)); + gb_vec2_sub(d, a, b); + gb_vec2_muleq(d, (float)(k >= 0.0f)); +} + +void gb_vec3_refract(gbVec3 *d, gbVec3 i, gbVec3 n, float eta) { + gbVec3 a, b; + float dv, k; + + dv = gb_vec3_dot(n, i); + k = 1.0f - eta*eta * (1.0f - dv*dv); + gb_vec3_mul(&a, i, eta); + gb_vec3_mul(&b, n, eta*dv*gb_sqrt(k)); + gb_vec3_sub(d, a, b); + gb_vec3_muleq(d, (float)(k >= 0.0f)); +} + + + + + +float gb_vec2_aspect_ratio(gbVec2 v) { return (v.y < 0.0001f) ? 0.0f : v.x/v.y; } + + + + + +void gb_mat2_transpose(gbMat2 *m) { gb_float22_transpose(gb_float22_m(m)); } +void gb_mat2_identity(gbMat2 *m) { gb_float22_identity(gb_float22_m(m)); } +void gb_mat2_mul(gbMat2 *out, gbMat2 *m1, gbMat2 *m2) { gb_float22_mul(gb_float22_m(out), gb_float22_m(m1), gb_float22_m(m2)); } + +void gb_float22_identity(float m[2][2]) { + m[0][0] = 1; m[0][1] = 0; + m[1][0] = 0; m[1][1] = 1; +} + +void gb_mat2_mul_vec2(gbVec2 *out, gbMat2 *m, gbVec2 in) { gb_float22_mul_vec2(out, gb_float22_m(m), in); } + +gbMat2 *gb_mat2_v(gbVec2 m[2]) { return (gbMat2 *)m; } +gbMat2 *gb_mat2_f(float m[2][2]) { return (gbMat2 *)m; } + +gbFloat2 *gb_float22_m(gbMat2 *m) { return (gbFloat2 *)m; } +gbFloat2 *gb_float22_v(gbVec2 m[2]) { return (gbFloat2 *)m; } +gbFloat2 *gb_float22_4(float m[4]) { return (gbFloat2 *)m; } + +void gb_float22_transpose(float (*vec)[2]) { + int i, j; + for (j = 0; j < 2; j++) { + for (i = j + 1; i < 2; i++) { + float t = vec[i][j]; + vec[i][j] = vec[j][i]; + vec[j][i] = t; + } + } +} + + + +void gb_float22_mul(float (*out)[2], float (*mat1)[2], float (*mat2)[2]) { + int i, j; + float temp1[2][2], temp2[2][2]; + if (mat1 == out) { gb__memcpy_4byte(temp1, mat1, sizeof(temp1)); mat1 = temp1; } + if (mat2 == out) { gb__memcpy_4byte(temp2, mat2, sizeof(temp2)); mat2 = temp2; } + for (j = 0; j < 2; j++) { + for (i = 0; i < 2; i++) { + out[j][i] = mat1[0][i]*mat2[j][0] + + mat1[1][i]*mat2[j][1]; + } + } +} + +void gb_float22_mul_vec2(gbVec2 *out, float m[2][2], gbVec2 v) { + out->x = m[0][0]*v.x + m[1][0]*v.y; + out->y = m[0][1]*v.x + m[1][1]*v.y; +} + +float gb_mat2_determinate(gbMat2 *m) { + gbFloat2 *e = gb_float22_m(m); + return e[0][0]*e[1][1] - e[1][0]*e[0][1]; +} + +void gb_mat2_inverse(gbMat2 *out, gbMat2 *in) { + gbFloat2 *o = gb_float22_m(out); + gbFloat2 *i = gb_float22_m(in); + + float ood = 1.0f / gb_mat2_determinate(in); + + o[0][0] = +i[1][1] * ood; + o[0][1] = -i[0][1] * ood; + o[1][0] = -i[1][0] * ood; + o[1][1] = +i[0][0] * ood; +} + + + + + + +void gb_mat3_transpose(gbMat3 *m) { gb_float33_transpose(gb_float33_m(m)); } +void gb_mat3_identity(gbMat3 *m) { gb_float33_identity(gb_float33_m(m)); } +void gb_mat3_mul(gbMat3 *out, gbMat3 *m1, gbMat3 *m2) { gb_float33_mul(gb_float33_m(out), gb_float33_m(m1), gb_float33_m(m2)); } + +void gb_float33_identity(float m[3][3]) { + m[0][0] = 1; m[0][1] = 0; m[0][2] = 0; + m[1][0] = 0; m[1][1] = 1; m[1][2] = 0; + m[2][0] = 0; m[2][1] = 0; m[2][2] = 1; +} + +void gb_mat3_mul_vec3(gbVec3 *out, gbMat3 *m, gbVec3 in) { gb_float33_mul_vec3(out, gb_float33_m(m), in); } + +gbMat3 *gb_mat3_v(gbVec3 m[3]) { return (gbMat3 *)m; } +gbMat3 *gb_mat3_f(float m[3][3]) { return (gbMat3 *)m; } + +gbFloat3 *gb_float33_m(gbMat3 *m) { return (gbFloat3 *)m; } +gbFloat3 *gb_float33_v(gbVec3 m[3]) { return (gbFloat3 *)m; } +gbFloat3 *gb_float33_9(float m[9]) { return (gbFloat3 *)m; } + +void gb_float33_transpose(float (*vec)[3]) { + int i, j; + for (j = 0; j < 3; j++) { + for (i = j + 1; i < 3; i++) { + float t = vec[i][j]; + vec[i][j] = vec[j][i]; + vec[j][i] = t; + } + } +} + +void gb_float33_mul(float (*out)[3], float (*mat1)[3], float (*mat2)[3]) { + int i, j; + float temp1[3][3], temp2[3][3]; + if (mat1 == out) { gb__memcpy_4byte(temp1, mat1, sizeof(temp1)); mat1 = temp1; } + if (mat2 == out) { gb__memcpy_4byte(temp2, mat2, sizeof(temp2)); mat2 = temp2; } + for (j = 0; j < 3; j++) { + for (i = 0; i < 3; i++) { + out[j][i] = mat1[0][i]*mat2[j][0] + + mat1[1][i]*mat2[j][1] + + mat1[2][i]*mat2[j][2]; + } + } +} + +void gb_float33_mul_vec3(gbVec3 *out, float m[3][3], gbVec3 v) { + out->x = m[0][0]*v.x + m[1][0]*v.y + m[2][0]*v.z; + out->y = m[0][1]*v.x + m[1][1]*v.y + m[2][1]*v.z; + out->z = m[0][2]*v.x + m[1][2]*v.y + m[2][2]*v.z; +} + + + +float gb_mat3_determinate(gbMat3 *m) { + gbFloat3 *e = gb_float33_m(m); + float d = +e[0][0] * (e[1][1] * e[2][2] - e[1][2] * e[2][1]) + -e[0][1] * (e[1][0] * e[2][2] - e[1][2] * e[2][0]) + +e[0][2] * (e[1][0] * e[2][1] - e[1][1] * e[2][0]); + return d; +} + +void gb_mat3_inverse(gbMat3 *out, gbMat3 *in) { + gbFloat3 *o = gb_float33_m(out); + gbFloat3 *i = gb_float33_m(in); + + float ood = 1.0f / gb_mat3_determinate(in); + + o[0][0] = +(i[1][1] * i[2][2] - i[2][1] * i[1][2]) * ood; + o[0][1] = -(i[1][0] * i[2][2] - i[2][0] * i[1][2]) * ood; + o[0][2] = +(i[1][0] * i[2][1] - i[2][0] * i[1][1]) * ood; + o[1][0] = -(i[0][1] * i[2][2] - i[2][1] * i[0][2]) * ood; + o[1][1] = +(i[0][0] * i[2][2] - i[2][0] * i[0][2]) * ood; + o[1][2] = -(i[0][0] * i[2][1] - i[2][0] * i[0][1]) * ood; + o[2][0] = +(i[0][1] * i[1][2] - i[1][1] * i[0][2]) * ood; + o[2][1] = -(i[0][0] * i[1][2] - i[1][0] * i[0][2]) * ood; + o[2][2] = +(i[0][0] * i[1][1] - i[1][0] * i[0][1]) * ood; +} + + + + + + + + + + + +void gb_mat4_transpose(gbMat4 *m) { gb_float44_transpose(gb_float44_m(m)); } +void gb_mat4_identity(gbMat4 *m) { gb_float44_identity(gb_float44_m(m)); } +void gb_mat4_mul(gbMat4 *out, gbMat4 *m1, gbMat4 *m2) { gb_float44_mul(gb_float44_m(out), gb_float44_m(m1), gb_float44_m(m2)); } + +void gb_float44_identity(float m[4][4]) { + m[0][0] = 1; m[0][1] = 0; m[0][2] = 0; m[0][3] = 0; + m[1][0] = 0; m[1][1] = 1; m[1][2] = 0; m[1][3] = 0; + m[2][0] = 0; m[2][1] = 0; m[2][2] = 1; m[2][3] = 0; + m[3][0] = 0; m[3][1] = 0; m[3][2] = 0; m[3][3] = 1; +} + +void gb_mat4_mul_vec4(gbVec4 *out, gbMat4 *m, gbVec4 in) { + gb_float44_mul_vec4(out, gb_float44_m(m), in); +} + +gbMat4 *gb_mat4_v(gbVec4 m[4]) { return (gbMat4 *)m; } +gbMat4 *gb_mat4_f(float m[4][4]) { return (gbMat4 *)m; } + +gbFloat4 *gb_float44_m(gbMat4 *m) { return (gbFloat4 *)m; } +gbFloat4 *gb_float44_v(gbVec4 m[4]) { return (gbFloat4 *)m; } +gbFloat4 *gb_float44_16(float m[16]) { return (gbFloat4 *)m; } + +void gb_float44_transpose(float (*vec)[4]) { + float tmp; + tmp = vec[1][0]; vec[1][0] = vec[0][1]; vec[0][1] = tmp; + tmp = vec[2][0]; vec[2][0] = vec[0][2]; vec[0][2] = tmp; + tmp = vec[3][0]; vec[3][0] = vec[0][3]; vec[0][3] = tmp; + tmp = vec[2][1]; vec[2][1] = vec[1][2]; vec[1][2] = tmp; + tmp = vec[3][1]; vec[3][1] = vec[1][3]; vec[1][3] = tmp; + tmp = vec[3][2]; vec[3][2] = vec[2][3]; vec[2][3] = tmp; +} + +void gb_float44_mul(float (*out)[4], float (*mat1)[4], float (*mat2)[4]) { + int i, j; + float temp1[4][4], temp2[4][4]; + if (mat1 == out) { gb__memcpy_4byte(temp1, mat1, sizeof(temp1)); mat1 = temp1; } + if (mat2 == out) { gb__memcpy_4byte(temp2, mat2, sizeof(temp2)); mat2 = temp2; } + for (j = 0; j < 4; j++) { + for (i = 0; i < 4; i++) { + out[j][i] = mat1[0][i]*mat2[j][0] + + mat1[1][i]*mat2[j][1] + + mat1[2][i]*mat2[j][2] + + mat1[3][i]*mat2[j][3]; + } + } +} + +void gb_float44_mul_vec4(gbVec4 *out, float m[4][4], gbVec4 v) { + out->x = m[0][0]*v.x + m[1][0]*v.y + m[2][0]*v.z + m[3][0]*v.w; + out->y = m[0][1]*v.x + m[1][1]*v.y + m[2][1]*v.z + m[3][1]*v.w; + out->z = m[0][2]*v.x + m[1][2]*v.y + m[2][2]*v.z + m[3][2]*v.w; + out->w = m[0][3]*v.x + m[1][3]*v.y + m[2][3]*v.z + m[3][3]*v.w; +} + +void gb_mat4_inverse(gbMat4 *out, gbMat4 *in) { + gbFloat4 *o = gb_float44_m(out); + gbFloat4 *m = gb_float44_m(in); + + float ood; + + float sf00 = m[2][2] * m[3][3] - m[3][2] * m[2][3]; + float sf01 = m[2][1] * m[3][3] - m[3][1] * m[2][3]; + float sf02 = m[2][1] * m[3][2] - m[3][1] * m[2][2]; + float sf03 = m[2][0] * m[3][3] - m[3][0] * m[2][3]; + float sf04 = m[2][0] * m[3][2] - m[3][0] * m[2][2]; + float sf05 = m[2][0] * m[3][1] - m[3][0] * m[2][1]; + float sf06 = m[1][2] * m[3][3] - m[3][2] * m[1][3]; + float sf07 = m[1][1] * m[3][3] - m[3][1] * m[1][3]; + float sf08 = m[1][1] * m[3][2] - m[3][1] * m[1][2]; + float sf09 = m[1][0] * m[3][3] - m[3][0] * m[1][3]; + float sf10 = m[1][0] * m[3][2] - m[3][0] * m[1][2]; + float sf11 = m[1][1] * m[3][3] - m[3][1] * m[1][3]; + float sf12 = m[1][0] * m[3][1] - m[3][0] * m[1][1]; + float sf13 = m[1][2] * m[2][3] - m[2][2] * m[1][3]; + float sf14 = m[1][1] * m[2][3] - m[2][1] * m[1][3]; + float sf15 = m[1][1] * m[2][2] - m[2][1] * m[1][2]; + float sf16 = m[1][0] * m[2][3] - m[2][0] * m[1][3]; + float sf17 = m[1][0] * m[2][2] - m[2][0] * m[1][2]; + float sf18 = m[1][0] * m[2][1] - m[2][0] * m[1][1]; + + o[0][0] = +(m[1][1] * sf00 - m[1][2] * sf01 + m[1][3] * sf02); + o[1][0] = -(m[1][0] * sf00 - m[1][2] * sf03 + m[1][3] * sf04); + o[2][0] = +(m[1][0] * sf01 - m[1][1] * sf03 + m[1][3] * sf05); + o[3][0] = -(m[1][0] * sf02 - m[1][1] * sf04 + m[1][2] * sf05); + + o[0][1] = -(m[0][1] * sf00 - m[0][2] * sf01 + m[0][3] * sf02); + o[1][1] = +(m[0][0] * sf00 - m[0][2] * sf03 + m[0][3] * sf04); + o[2][1] = -(m[0][0] * sf01 - m[0][1] * sf03 + m[0][3] * sf05); + o[3][1] = +(m[0][0] * sf02 - m[0][1] * sf04 + m[0][2] * sf05); + + o[0][2] = +(m[0][1] * sf06 - m[0][2] * sf07 + m[0][3] * sf08); + o[1][2] = -(m[0][0] * sf06 - m[0][2] * sf09 + m[0][3] * sf10); + o[2][2] = +(m[0][0] * sf11 - m[0][1] * sf09 + m[0][3] * sf12); + o[3][2] = -(m[0][0] * sf08 - m[0][1] * sf10 + m[0][2] * sf12); + + o[0][3] = -(m[0][1] * sf13 - m[0][2] * sf14 + m[0][3] * sf15); + o[1][3] = +(m[0][0] * sf13 - m[0][2] * sf16 + m[0][3] * sf17); + o[2][3] = -(m[0][0] * sf14 - m[0][1] * sf16 + m[0][3] * sf18); + o[3][3] = +(m[0][0] * sf15 - m[0][1] * sf17 + m[0][2] * sf18); + + ood = 1.0f / (m[0][0] * o[0][0] + + m[0][1] * o[1][0] + + m[0][2] * o[2][0] + + m[0][3] * o[3][0]); + + o[0][0] *= ood; + o[0][1] *= ood; + o[0][2] *= ood; + o[0][3] *= ood; + o[1][0] *= ood; + o[1][1] *= ood; + o[1][2] *= ood; + o[1][3] *= ood; + o[2][0] *= ood; + o[2][1] *= ood; + o[2][2] *= ood; + o[2][3] *= ood; + o[3][0] *= ood; + o[3][1] *= ood; + o[3][2] *= ood; + o[3][3] *= ood; +} + + + + + + + +void gb_mat4_translate(gbMat4 *out, gbVec3 v) { + gb_mat4_identity(out); + out->col[3].xyz = v; + out->col[3].w = 1; +} + +void gb_mat4_rotate(gbMat4 *out, gbVec3 v, float angle_radians) { + float c, s; + gbVec3 axis, t; + gbFloat4 *rot; + + c = gb_cos(angle_radians); + s = gb_sin(angle_radians); + + gb_vec3_norm(&axis, v); + gb_vec3_mul(&t, axis, 1.0f-c); + + gb_mat4_identity(out); + rot = gb_float44_m(out); + + rot[0][0] = c + t.x*axis.x; + rot[0][1] = 0 + t.x*axis.y + s*axis.z; + rot[0][2] = 0 + t.x*axis.z - s*axis.y; + rot[0][3] = 0; + + rot[1][0] = 0 + t.y*axis.x - s*axis.z; + rot[1][1] = c + t.y*axis.y; + rot[1][2] = 0 + t.y*axis.z + s*axis.x; + rot[1][3] = 0; + + rot[2][0] = 0 + t.z*axis.x + s*axis.y; + rot[2][1] = 0 + t.z*axis.y - s*axis.x; + rot[2][2] = c + t.z*axis.z; + rot[2][3] = 0; +} + +void gb_mat4_scale(gbMat4 *out, gbVec3 v) { + gb_mat4_identity(out); + out->e[0] = v.x; + out->e[5] = v.y; + out->e[10] = v.z; +} + +void gb_mat4_scalef(gbMat4 *out, float s) { + gb_mat4_identity(out); + out->e[0] = s; + out->e[5] = s; + out->e[10] = s; +} + + +void gb_mat4_ortho2d(gbMat4 *out, float left, float right, float bottom, float top) { + gbFloat4 *m; + gb_mat4_identity(out); + m = gb_float44_m(out); + + m[0][0] = 2.0f / (right - left); + m[1][1] = 2.0f / (top - bottom); + m[2][2] = -1.0f; + m[3][0] = -(right + left) / (right - left); + m[3][1] = -(top + bottom) / (top - bottom); +} + +void gb_mat4_ortho3d(gbMat4 *out, float left, float right, float bottom, float top, float z_near, float z_far) { + gbFloat4 *m; + gb_mat4_identity(out); + m = gb_float44_m(out); + + m[0][0] = +2.0f / (right - left); + m[1][1] = +2.0f / (top - bottom); + m[2][2] = -2.0f / (z_far - z_near); + m[3][0] = -(right + left) / (right - left); + m[3][1] = -(top + bottom) / (top - bottom); + m[3][2] = -(z_far + z_near) / (z_far - z_near); +} + + +void gb_mat4_perspective(gbMat4 *out, float fovy, float aspect, float z_near, float z_far) { + float tan_half_fovy = gb_tan(0.5f * fovy); + gbMat4 zero_mat = {0}; + gbFloat4 *m = gb_float44_m(out); + *out = zero_mat; + + m[0][0] = 1.0f / (aspect*tan_half_fovy); + m[1][1] = 1.0f / (tan_half_fovy); + m[2][2] = -(z_far + z_near) / (z_far - z_near); + m[2][3] = -1.0f; + m[3][2] = -2.0f*z_far*z_near / (z_far - z_near); +} + +void gb_mat4_infinite_perspective(gbMat4 *out, float fovy, float aspect, float z_near) { + float range = gb_tan(0.5f * fovy) * z_near; + float left = -range * aspect; + float right = range * aspect; + float bottom = -range; + float top = range; + gbMat4 zero_mat = {0}; + gbFloat4 *m = gb_float44_m(out); + *out = zero_mat; + + m[0][0] = (2.0f*z_near) / (right - left); + m[1][1] = (2.0f*z_near) / (top - bottom); + m[2][2] = -1.0f; + m[2][3] = -1.0f; + m[3][2] = -2.0f*z_near; +} + +void gb_mat4_look_at(gbMat4 *out, gbVec3 eye, gbVec3 centre, gbVec3 up) { + gbVec3 f, s, u; + gbFloat4 *m; + + gb_vec3_sub(&f, centre, eye); + gb_vec3_norm(&f, f); + + gb_vec3_cross(&s, f, up); + gb_vec3_norm(&s, s); + + gb_vec3_cross(&u, s, f); + + gb_mat4_identity(out); + m = gb_float44_m(out); + + m[0][0] = +s.x; + m[1][0] = +s.y; + m[2][0] = +s.z; + + m[0][1] = +u.x; + m[1][1] = +u.y; + m[2][1] = +u.z; + + m[0][2] = -f.x; + m[1][2] = -f.y; + m[2][2] = -f.z; + + m[3][0] = -gb_vec3_dot(s, eye); + m[3][1] = -gb_vec3_dot(u, eye); + m[3][2] = +gb_vec3_dot(f, eye); +} + + + + + + + + + + + + +gbQuat gb_quat(float x, float y, float z, float w) { gbQuat q; q.x = x; q.y = y; q.z = z; q.w = w; return q; } +gbQuat gb_quatv(float e[4]) { gbQuat q; q.x = e[0]; q.y = e[1]; q.z = e[2]; q.w = e[3]; return q; } + +gbQuat gb_quat_axis_angle(gbVec3 axis, float angle_radians) { + gbQuat q; + gb_vec3_norm(&q.xyz, axis); + gb_vec3_muleq(&q.xyz, gb_sin(0.5f*angle_radians)); + q.w = gb_cos(0.5f*angle_radians); + return q; +} + +gbQuat gb_quat_euler_angles(float pitch, float yaw, float roll) { + /* TODO(bill): Do without multiplication, i.e. make it faster */ + gbQuat q, p, y, r; + p = gb_quat_axis_angle(gb_vec3(1, 0, 0), pitch); + y = gb_quat_axis_angle(gb_vec3(0, 1, 0), yaw); + r = gb_quat_axis_angle(gb_vec3(0, 0, 1), roll); + + gb_quat_mul(&q, y, p); + gb_quat_muleq(&q, r); + + return q; +} + +gbQuat gb_quat_identity(void) { gbQuat q = {0, 0, 0, 1}; return q; } + + +void gb_quat_add(gbQuat *d, gbQuat q0, gbQuat q1) { gb_vec4_add(&d->xyzw, q0.xyzw, q1.xyzw); } +void gb_quat_sub(gbQuat *d, gbQuat q0, gbQuat q1) { gb_vec4_sub(&d->xyzw, q0.xyzw, q1.xyzw); } + +void gb_quat_mul(gbQuat *d, gbQuat q0, gbQuat q1) { + d->x = q0.w * q1.x + q0.x * q1.w + q0.y * q1.z - q0.z * q1.y; + d->y = q0.w * q1.y - q0.x * q1.z + q0.y * q1.w + q0.z * q1.x; + d->z = q0.w * q1.z + q0.x * q1.y - q0.y * q1.x + q0.z * q1.w; + d->w = q0.w * q1.w - q0.x * q1.x - q0.y * q1.y - q0.z * q1.z; +} + +void gb_quat_div(gbQuat *d, gbQuat q0, gbQuat q1){ gbQuat iq1; gb_quat_inverse(&iq1, q1); gb_quat_mul(d, q0, iq1); } + +void gb_quat_mulf(gbQuat *d, gbQuat q0, float s) { gb_vec4_mul(&d->xyzw, q0.xyzw, s); } +void gb_quat_divf(gbQuat *d, gbQuat q0, float s) { gb_vec4_div(&d->xyzw, q0.xyzw, s); } + + +void gb_quat_addeq(gbQuat *d, gbQuat q) { gb_vec4_addeq(&d->xyzw, q.xyzw); } +void gb_quat_subeq(gbQuat *d, gbQuat q) { gb_vec4_subeq(&d->xyzw, q.xyzw); } +void gb_quat_muleq(gbQuat *d, gbQuat q) { gb_quat_mul(d, *d, q); } +void gb_quat_diveq(gbQuat *d, gbQuat q) { gb_quat_div(d, *d, q); } + + +void gb_quat_muleqf(gbQuat *d, float s) { gb_vec4_muleq(&d->xyzw, s); } +void gb_quat_diveqf(gbQuat *d, float s) { gb_vec4_diveq(&d->xyzw, s); } + +float gb_quat_dot(gbQuat q0, gbQuat q1) { float r = gb_vec3_dot(q0.xyz, q1.xyz) + q0.w*q1.w; return r; } +float gb_quat_mag(gbQuat q) { float r = gb_sqrt(gb_quat_dot(q, q)); return r; } + +void gb_quat_norm(gbQuat *d, gbQuat q) { gb_quat_divf(d, q, gb_quat_mag(q)); } +void gb_quat_conj(gbQuat *d, gbQuat q) { d->xyz = gb_vec3(-q.x, -q.y, -q.z); d->w = q.w; } +void gb_quat_inverse(gbQuat *d, gbQuat q) { gb_quat_conj(d, q); gb_quat_diveqf(d, gb_quat_dot(q, q)); } + + +void gb_quat_axis(gbVec3 *axis, gbQuat q) { + gbQuat n; gb_quat_norm(&n, q); + gb_vec3_div(axis, n.xyz, gb_sin(gb_arccos(q.w))); +} + +float gb_quat_angle(gbQuat q) { + float mag = gb_quat_mag(q); + float c = q.w * (1.0f/mag); + float angle = 2.0f*gb_arccos(c); + return angle; +} + + +float gb_quat_roll(gbQuat q) { return gb_arctan2(2.0f*q.x*q.y + q.z*q.w, q.x*q.x + q.w*q.w - q.y*q.y - q.z*q.z); } +float gb_quat_pitch(gbQuat q) { return gb_arctan2(2.0f*q.y*q.z + q.w*q.x, q.w*q.w - q.x*q.x - q.y*q.y + q.z*q.z); } +float gb_quat_yaw(gbQuat q) { return gb_arcsin(-2.0f*(q.x*q.z - q.w*q.y)); } + +void gb_quat_rotate_vec3(gbVec3 *d, gbQuat q, gbVec3 v) { + /* gbVec3 t = 2.0f * cross(q.xyz, v); + * *d = q.w*t + v + cross(q.xyz, t); + */ + gbVec3 t, p; + gb_vec3_cross(&t, q.xyz, v); + gb_vec3_muleq(&t, 2.0f); + + gb_vec3_cross(&p, q.xyz, t); + + gb_vec3_mul(d, t, q.w); + gb_vec3_addeq(d, v); + gb_vec3_addeq(d, p); +} + + +void gb_mat4_from_quat(gbMat4 *out, gbQuat q) { + gbFloat4 *m; + gbQuat a; + float xx, yy, zz, + xy, xz, yz, + wx, wy, wz; + + gb_quat_norm(&a, q); + xx = a.x*a.x; yy = a.y*a.y; zz = a.z*a.z; + xy = a.x*a.y; xz = a.x*a.z; yz = a.y*a.z; + wx = a.w*a.x; wy = a.w*a.y; wz = a.w*a.z; + + gb_mat4_identity(out); + m = gb_float44_m(out); + + m[0][0] = 1.0f - 2.0f*(yy + zz); + m[0][1] = 2.0f*(xy + wz); + m[0][2] = 2.0f*(xz - wy); + + m[1][0] = 2.0f*(xy - wz); + m[1][1] = 1.0f - 2.0f*(xx + zz); + m[1][2] = 2.0f*(yz + wx); + + m[2][0] = 2.0f*(xz + wy); + m[2][1] = 2.0f*(yz - wx); + m[2][2] = 1.0f - 2.0f*(xx + yy); +} + +void gb_quat_from_mat4(gbQuat *out, gbMat4 *mat) { + gbFloat4 *m; + float four_x_squared_minus_1, four_y_squared_minus_1, + four_z_squared_minus_1, four_w_squared_minus_1, + four_biggest_squared_minus_1; + int biggest_index = 0; + float biggest_value, mult; + + m = gb_float44_m(mat); + + four_x_squared_minus_1 = m[0][0] - m[1][1] - m[2][2]; + four_y_squared_minus_1 = m[1][1] - m[0][0] - m[2][2]; + four_z_squared_minus_1 = m[2][2] - m[0][0] - m[1][1]; + four_w_squared_minus_1 = m[0][0] + m[1][1] + m[2][2]; + + four_biggest_squared_minus_1 = four_w_squared_minus_1; + if (four_x_squared_minus_1 > four_biggest_squared_minus_1) { + four_biggest_squared_minus_1 = four_x_squared_minus_1; + biggest_index = 1; + } + if (four_y_squared_minus_1 > four_biggest_squared_minus_1) { + four_biggest_squared_minus_1 = four_y_squared_minus_1; + biggest_index = 2; + } + if (four_z_squared_minus_1 > four_biggest_squared_minus_1) { + four_biggest_squared_minus_1 = four_z_squared_minus_1; + biggest_index = 3; + } + + biggest_value = gb_sqrt(four_biggest_squared_minus_1 + 1.0f) * 0.5f; + mult = 0.25f / biggest_value; + + switch (biggest_index) { + case 0: + out->w = biggest_value; + out->x = (m[1][2] - m[2][1]) * mult; + out->y = (m[2][0] - m[0][2]) * mult; + out->z = (m[0][1] - m[1][0]) * mult; + break; + case 1: + out->w = (m[1][2] - m[2][1]) * mult; + out->x = biggest_value; + out->y = (m[0][1] + m[1][0]) * mult; + out->z = (m[2][0] + m[0][2]) * mult; + break; + case 2: + out->w = (m[2][0] - m[0][2]) * mult; + out->x = (m[0][1] + m[1][0]) * mult; + out->y = biggest_value; + out->z = (m[1][2] + m[2][1]) * mult; + break; + case 3: + out->w = (m[0][1] - m[1][0]) * mult; + out->x = (m[2][0] + m[0][2]) * mult; + out->y = (m[1][2] + m[2][1]) * mult; + out->z = biggest_value; + break; + default: + /* NOTE(bill): This shouldn't fucking happen!!! */ + break; + } + +} + + + + + + +float gb_lerp (float a, float b, float t) { return a*(1.0f-t) + b*t; } +float gb_unlerp (float t, float a, float b) { return (t-a)/(b-a); } +float gb_smooth_step (float a, float b, float t) { float x = (t - a)/(b - a); return x*x*(3.0f - 2.0f*x); } +float gb_smoother_step(float a, float b, float t) { float x = (t - a)/(b - a); return x*x*x*(x*(6.0f*x - 15.0f) + 10.0f); } + + +#define GB_VEC_LERPN(N, d, a, b, t) \ + gbVec##N db; \ + gb_vec##N##_sub(&db, b, a); \ + gb_vec##N##_muleq(&db, t); \ + gb_vec##N##_add(d, a, db) +void gb_vec2_lerp(gbVec2 *d, gbVec2 a, gbVec2 b, float t) { GB_VEC_LERPN(2, d, a, b, t); } +void gb_vec3_lerp(gbVec3 *d, gbVec3 a, gbVec3 b, float t) { GB_VEC_LERPN(3, d, a, b, t); } +void gb_vec4_lerp(gbVec4 *d, gbVec4 a, gbVec4 b, float t) { GB_VEC_LERPN(4, d, a, b, t); } + +#undef GB_VEC_LERPN + +void gb_quat_lerp(gbQuat *d, gbQuat a, gbQuat b, float t) { gb_vec4_lerp(&d->xyzw, a.xyzw, b.xyzw, t); } +void gb_quat_nlerp(gbQuat *d, gbQuat a, gbQuat b, float t) { gb_quat_lerp(d, a, b, t); gb_quat_norm(d, *d); } + +void gb_quat_slerp(gbQuat *d, gbQuat a, gbQuat b, float t) { + gbQuat x, y, z; + float cos_theta, angle; + float s1, s0, is; + + z = b; + cos_theta = gb_quat_dot(a, b); + + if (cos_theta < 0.0f) { + z = gb_quat(-b.x, -b.y, -b.z, -b.w); + cos_theta = -cos_theta; + } + + if (cos_theta > 1.0f) { + /* NOTE(bill): Use lerp not nlerp as it's not a real angle or they are not normalized */ + gb_quat_lerp(d, a, b, t); + } + + angle = gb_arccos(cos_theta); + + s1 = gb_sin((1.0f - t)*angle); + s0 = gb_sin(t*angle); + is = 1.0f/gb_sin(angle); + gb_quat_mulf(&x, a, s1); + gb_quat_mulf(&y, z, s0); + gb_quat_add(d, x, y); + gb_quat_muleqf(d, is); +} + +void gb_quat_slerp_approx(gbQuat *d, gbQuat a, gbQuat b, float t) { + /* NOTE(bill): Derived by taylor expanding the geometric interpolation equation + * Even works okay for nearly anti-parallel versors!!! + */ + /* NOTE(bill): Extra interations cannot be used as they require angle^4 which is not worth it to approximate */ + float tp = t + (1.0f - gb_quat_dot(a, b))/3.0f * t*(-2.0f*t*t + 3.0f*t - 1.0f); + gb_quat_nlerp(d, a, b, tp); +} + +void gb_quat_nquad(gbQuat *d, gbQuat p, gbQuat a, gbQuat b, gbQuat q, float t) { + gbQuat x, y; + gb_quat_nlerp(&x, p, q, t); + gb_quat_nlerp(&y, a, b, t); + gb_quat_nlerp(d, x, y, 2.0f*t*(1.0f-t)); +} + +void gb_quat_squad(gbQuat *d, gbQuat p, gbQuat a, gbQuat b, gbQuat q, float t) { + gbQuat x, y; + gb_quat_slerp(&x, p, q, t); + gb_quat_slerp(&y, a, b, t); + gb_quat_slerp(d, x, y, 2.0f*t*(1.0f-t)); +} + +void gb_quat_squad_approx(gbQuat *d, gbQuat p, gbQuat a, gbQuat b, gbQuat q, float t) { + gbQuat x, y; + gb_quat_slerp_approx(&x, p, q, t); + gb_quat_slerp_approx(&y, a, b, t); + gb_quat_slerp_approx(d, x, y, 2.0f*t*(1.0f-t)); +} + + + + + + +gbRect2 gb_rect2(gbVec2 pos, gbVec2 dim) { + gbRect2 r; + r.pos = pos; + r.dim = dim; + return r; +} + +gbRect2 gb_rect2v(float v[4]) { + gbRect2 r; + r.pos = gb_vec2v(&v[0]); + r.dim = gb_vec2v(&v[2]); + return r; +} + +gbRect3 gb_rect3(gbVec3 pos, gbVec3 dim) { + gbRect3 r; + r.pos = pos; + r.dim = dim; + return r; +} + +gbRect3 gb_rect3v(float v[6]) { + gbRect3 r; + r.pos = gb_vec3v(&v[0]); + r.dim = gb_vec3v(&v[3]); + return r; +} + + +int gb_rect2_contains(gbRect2 a, float x, float y) { + float min_x = gb_min(a.pos.x, a.pos.x+a.dim.x); + float max_x = gb_max(a.pos.x, a.pos.x+a.dim.x); + float min_y = gb_min(a.pos.y, a.pos.y+a.dim.y); + float max_y = gb_max(a.pos.y, a.pos.y+a.dim.y); + int result = (x >= min_x) & (x < max_x) & (y >= min_y) & (y < max_y); + return result; +} + +int gb_rect2_contains_vec2(gbRect2 a, gbVec2 p) { return gb_rect2_contains(a, p.x, p.y); } + +int gb_rect2_intersects(gbRect2 a, gbRect2 b) { + gbRect2 r = {0}; + return gb_rect2_intersection_result(a, b, &r); +} + +int gb_rect2_intersection_result(gbRect2 a, gbRect2 b, gbRect2 *intersection) { + float a_min_x = gb_min(a.pos.x, a.pos.x+a.dim.x); + float a_max_x = gb_max(a.pos.x, a.pos.x+a.dim.x); + float a_min_y = gb_min(a.pos.y, a.pos.y+a.dim.y); + float a_max_y = gb_max(a.pos.y, a.pos.y+a.dim.y); + + float b_min_x = gb_min(b.pos.x, b.pos.x+b.dim.x); + float b_max_x = gb_max(b.pos.x, b.pos.x+b.dim.x); + float b_min_y = gb_min(b.pos.y, b.pos.y+b.dim.y); + float b_max_y = gb_max(b.pos.y, b.pos.y+b.dim.y); + + float x0 = gb_max(a_min_x, b_min_x); + float y0 = gb_max(a_min_y, b_min_y); + float x1 = gb_min(a_max_x, b_max_x); + float y1 = gb_min(a_max_y, b_max_y); + + if ((x0 < x1) && (y0 < y1)) { + gbRect2 r = gb_rect2(gb_vec2(x0, y0), gb_vec2(x1-x0, y1-y0)); + *intersection = r; + return 1; + } else { + gbRect2 r = {0}; + *intersection = r; + return 0; + } +} + + +#if defined(_WIN64) || defined(__x86_64__) || defined(__ppc64__) + gb_math_u64 gb_hash_murmur64(void const *key, size_t num_bytes, gb_math_u64 seed) { + gb_math_u64 const m = 0xc6a4a7935bd1e995ULL; + gb_math_u64 const r = 47; + + gb_math_u64 h = seed ^ (num_bytes * m); + + gb_math_u64 *data = (gb_math_u64 *)(key); + gb_math_u64 *end = data + (num_bytes / 8); + unsigned char *data2; + + while (data != end) { + gb_math_u64 k = *data++; + k *= m; + k ^= k >> r; + k *= m; + h ^= k; + h *= m; + } + + data2 = (unsigned char *)data; + + switch (num_bytes & 7) { + case 7: h ^= (gb_math_u64)data2[6] << 48; + case 6: h ^= (gb_math_u64)data2[5] << 40; + case 5: h ^= (gb_math_u64)data2[4] << 32; + case 4: h ^= (gb_math_u64)data2[3] << 24; + case 3: h ^= (gb_math_u64)data2[2] << 16; + case 2: h ^= (gb_math_u64)data2[1] << 8; + case 1: h ^= (gb_math_u64)data2[0]; + h *= m; + }; + + h ^= h >> r; + h *= m; + h ^= h >> r; + + return h; + } +#else + gb_math_u64 gb_hash_murmur64(void const *key, size_t num_bytes, gb_math_u64 seed) { + gb_math_u32 const m = 0x5bd1e995; + gb_math_u32 const r = 24; + + gb_math_u64 h = 0; + gb_math_u32 h1 = (gb_math_u32)seed ^ (gb_math_u32)num_bytes; + gb_math_u32 h2 = (gb_math_u32)((gb_math_u64)seed >> 32); + + gb_math_u32 *data = (gb_math_u32 *)key; + + + while (num_bytes >= 8) { + gb_math_u32 k1, k2; + k1 = *data++; + k1 *= m; + k1 ^= k1 >> r; + k1 *= m; + h1 *= m; + h1 ^= k1; + num_bytes -= 4; + + k2 = *data++; + k2 *= m; + k2 ^= k2 >> r; + k2 *= m; + h2 *= m; + h2 ^= k2; + num_bytes -= 4; + } + + if (num_bytes >= 4) { + gb_math_u32 k1 = *data++; + k1 *= m; + k1 ^= k1 >> r; + k1 *= m; + h1 *= m; + h1 ^= k1; + num_bytes -= 4; + } + + switch (num_bytes) { + gb_math_u32 a, b, c; + case 3: c = data[2]; h2 ^= c << 16; + case 2: b = data[1]; h2 ^= b << 8; + case 1: a = data[0]; h2 ^= a << 0; + h2 *= m; + }; + + h1 ^= h2 >> 18; + h1 *= m; + h2 ^= h1 >> 22; + h2 *= m; + h1 ^= h2 >> 17; + h1 *= m; + h2 ^= h1 >> 19; + h2 *= m; + + h = (gb_math_u64)(h << 32) | (gb_math_u64)h2; + + return h; + } +#endif + + +/* TODO(bill): Make better random number generators */ +float gb_random_range_float(float min_inc, float max_inc) { + int int_result = gb_random_range_int(0, 2147483646); /* Prevent integer overflow */ + float result = int_result/(float)2147483646; + result *= max_inc - min_inc; + result += min_inc; + return result; +} + +int gb_random_range_int(int min_inc, int max_inc) { + static unsigned int random_value = 0xdeadbeef; /* Random Value */ + unsigned int diff, result; + random_value = random_value * 2147001325 + 715136305; /* BCPL generator */ + diff = max_inc - min_inc + 1; + result = random_value % diff; + result += min_inc; + + return result; +} + +float gb_random01(void) { + return gb_random_range_float(0.0f, 1.0f); +} + +#if defined(__GCC__) || defined(__GNUC__) +#pragma GCC diagnostic pop +#elif defined(__clang__) +#pragma clang diagnostic pop +#endif + + + +#endif /* GB_MATH_IMPLEMENTATION */ diff --git a/src/gb_math.zig b/src/gb_math.zig new file mode 100644 index 000000000..5a568d04c --- /dev/null +++ b/src/gb_math.zig @@ -0,0 +1,3 @@ +pub usingnamespace @cImport({ + @cInclude("gb_math.h"); +});