//! Rendering implementation for OpenGL. pub const OpenGL = @This(); const std = @import("std"); const builtin = @import("builtin"); const glfw = @import("glfw"); const assert = std.debug.assert; const testing = std.testing; const Allocator = std.mem.Allocator; const apprt = @import("../apprt.zig"); const configpkg = @import("../config.zig"); const font = @import("../font/main.zig"); const imgui = @import("imgui"); const renderer = @import("../renderer.zig"); const terminal = @import("../terminal/main.zig"); const Terminal = terminal.Terminal; const gl = @import("opengl/main.zig"); const trace = @import("tracy").trace; const math = @import("../math.zig"); const Surface = @import("../Surface.zig"); const log = std.log.scoped(.grid); /// The runtime can request a single-threaded draw by setting this boolean /// to true. In this case, the renderer.draw() call is expected to be called /// from the runtime. pub const single_threaded_draw = if (@hasDecl(apprt.Surface, "opengl_single_threaded_draw")) apprt.Surface.opengl_single_threaded_draw else false; const DrawMutex = if (single_threaded_draw) std.Thread.Mutex else void; const drawMutexZero = if (DrawMutex == void) void{} else .{}; alloc: std.mem.Allocator, /// The configuration we need derived from the main config. config: DerivedConfig, /// Current cell dimensions for this grid. cell_size: renderer.CellSize, /// Current screen size dimensions for this grid. This is set on the first /// resize event, and is not immediately available. screen_size: ?renderer.ScreenSize, /// The current set of cells to render. Each set of cells goes into /// a separate shader call. cells_bg: std.ArrayListUnmanaged(GPUCell), cells: std.ArrayListUnmanaged(GPUCell), /// The size of the cells list that was sent to the GPU. This is used /// to detect when the cells array was reallocated/resized and handle that /// accordingly. gl_cells_size: usize = 0, /// The last length of the cells that was written to the GPU. This is used to /// determine what data needs to be rewritten on the GPU. gl_cells_written: usize = 0, /// Shader program for cell rendering. gl_state: ?GLState = null, /// The font structures. font_group: *font.GroupCache, font_shaper: font.Shaper, /// True if the window is focused focused: bool, /// Padding options padding: renderer.Options.Padding, /// The mailbox for communicating with the window. surface_mailbox: apprt.surface.Mailbox, /// Deferred operations. This is used to apply changes to the OpenGL context. /// Some runtimes (GTK) do not support multi-threading so to keep our logic /// simple we apply all OpenGL context changes in the render() call. deferred_screen_size: ?SetScreenSize = null, deferred_font_size: ?SetFontSize = null, /// If we're drawing with single threaded operations draw_mutex: DrawMutex = drawMutexZero, /// Current background to draw. This may not match self.background if the /// terminal is in reversed mode. draw_background: terminal.color.RGB, /// Defererred OpenGL operation to update the screen size. const SetScreenSize = struct { size: renderer.ScreenSize, fn apply(self: SetScreenSize, r: *const OpenGL) !void { const gl_state = r.gl_state orelse return error.OpenGLUninitialized; // Apply our padding const padding = r.padding.explicit.add(if (r.padding.balance) renderer.Padding.balanced(self.size, r.gridSize(self.size), r.cell_size) else .{}); const padded_size = self.size.subPadding(padding); log.debug("GL api: screen size padded={} screen={} grid={} cell={} padding={}", .{ padded_size, self.size, r.gridSize(self.size), r.cell_size, r.padding.explicit, }); // Update our viewport for this context to be the entire window. // OpenGL works in pixels, so we have to use the pixel size. try gl.viewport( 0, 0, @intCast(self.size.width), @intCast(self.size.height), ); // Update the projection uniform within our shader try gl_state.program.setUniform( "projection", // 2D orthographic projection with the full w/h math.ortho2d( -1 * @as(f32, @floatFromInt(padding.left)), @floatFromInt(padded_size.width + padding.right), @floatFromInt(padded_size.height + padding.bottom), -1 * @as(f32, @floatFromInt(padding.top)), ), ); } }; const SetFontSize = struct { metrics: font.face.Metrics, fn apply(self: SetFontSize, r: *const OpenGL) !void { const gl_state = r.gl_state orelse return error.OpenGLUninitialized; try gl_state.program.setUniform( "cell_size", @Vector(2, f32){ @floatFromInt(self.metrics.cell_width), @floatFromInt(self.metrics.cell_height), }, ); try gl_state.program.setUniform( "strikethrough_position", @as(f32, @floatFromInt(self.metrics.strikethrough_position)), ); try gl_state.program.setUniform( "strikethrough_thickness", @as(f32, @floatFromInt(self.metrics.strikethrough_thickness)), ); } }; /// The raw structure that maps directly to the buffer sent to the vertex shader. /// This must be "extern" so that the field order is not reordered by the /// Zig compiler. const GPUCell = extern struct { /// vec2 grid_coord grid_col: u16, grid_row: u16, /// vec2 glyph_pos glyph_x: u32 = 0, glyph_y: u32 = 0, /// vec2 glyph_size glyph_width: u32 = 0, glyph_height: u32 = 0, /// vec2 glyph_size glyph_offset_x: i32 = 0, glyph_offset_y: i32 = 0, /// vec4 fg_color_in fg_r: u8, fg_g: u8, fg_b: u8, fg_a: u8, /// vec4 bg_color_in bg_r: u8, bg_g: u8, bg_b: u8, bg_a: u8, /// uint mode mode: GPUCellMode, /// The width in grid cells that a rendering takes. grid_width: u8, }; const GPUCellMode = enum(u8) { bg = 1, fg = 2, fg_color = 7, strikethrough = 8, // Non-exhaustive because masks change it _, /// Apply a mask to the mode. pub fn mask(self: GPUCellMode, m: GPUCellMode) GPUCellMode { return @enumFromInt(@intFromEnum(self) | @intFromEnum(m)); } }; /// The configuration for this renderer that is derived from the main /// configuration. This must be exported so that we don't need to /// pass around Config pointers which makes memory management a pain. pub const DerivedConfig = struct { font_thicken: bool, font_features: std.ArrayList([]const u8), font_styles: font.Group.StyleStatus, cursor_color: ?terminal.color.RGB, cursor_text: ?terminal.color.RGB, background: terminal.color.RGB, background_opacity: f64, foreground: terminal.color.RGB, selection_background: ?terminal.color.RGB, selection_foreground: ?terminal.color.RGB, pub fn init( alloc_gpa: Allocator, config: *const configpkg.Config, ) !DerivedConfig { // Copy our font features var font_features = features: { var clone = try config.@"font-feature".list.clone(alloc_gpa); break :features clone.toManaged(alloc_gpa); }; errdefer font_features.deinit(); // Get our font styles var font_styles = font.Group.StyleStatus.initFill(true); font_styles.set(.bold, config.@"font-style-bold" != .false); font_styles.set(.italic, config.@"font-style-italic" != .false); font_styles.set(.bold_italic, config.@"font-style-bold-italic" != .false); return .{ .background_opacity = @max(0, @min(1, config.@"background-opacity")), .font_thicken = config.@"font-thicken", .font_features = font_features, .font_styles = font_styles, .cursor_color = if (config.@"cursor-color") |col| col.toTerminalRGB() else null, .cursor_text = if (config.@"cursor-text") |txt| txt.toTerminalRGB() else null, .background = config.background.toTerminalRGB(), .foreground = config.foreground.toTerminalRGB(), .selection_background = if (config.@"selection-background") |bg| bg.toTerminalRGB() else null, .selection_foreground = if (config.@"selection-foreground") |bg| bg.toTerminalRGB() else null, }; } pub fn deinit(self: *DerivedConfig) void { self.font_features.deinit(); } }; pub fn init(alloc: Allocator, options: renderer.Options) !OpenGL { // Create the initial font shaper var shaper = try font.Shaper.init(alloc, .{ .features = options.config.font_features.items, }); errdefer shaper.deinit(); // Setup our font metrics uniform const metrics = try resetFontMetrics( alloc, options.font_group, options.config.font_thicken, ); var gl_state = try GLState.init(options.font_group); errdefer gl_state.deinit(); return OpenGL{ .alloc = alloc, .config = options.config, .cells_bg = .{}, .cells = .{}, .cell_size = .{ .width = metrics.cell_width, .height = metrics.cell_height }, .screen_size = null, .gl_state = gl_state, .font_group = options.font_group, .font_shaper = shaper, .draw_background = options.config.background, .focused = true, .padding = options.padding, .surface_mailbox = options.surface_mailbox, .deferred_font_size = .{ .metrics = metrics }, }; } pub fn deinit(self: *OpenGL) void { self.font_shaper.deinit(); if (self.gl_state) |*v| v.deinit(); self.cells.deinit(self.alloc); self.cells_bg.deinit(self.alloc); self.config.deinit(); self.* = undefined; } /// Returns the hints that we want for this pub fn glfwWindowHints(config: *const configpkg.Config) glfw.Window.Hints { return .{ .context_version_major = 3, .context_version_minor = 3, .opengl_profile = .opengl_core_profile, .opengl_forward_compat = true, .cocoa_graphics_switching = builtin.os.tag == .macos, .cocoa_retina_framebuffer = true, .transparent_framebuffer = config.@"background-opacity" < 1, }; } /// This is called early right after surface creation. pub fn surfaceInit(surface: *apprt.Surface) !void { // Treat this like a thread entry const self: OpenGL = undefined; switch (apprt.runtime) { else => @compileError("unsupported app runtime for OpenGL"), apprt.gtk => { // GTK uses global OpenGL context so we load from null. const version = try gl.glad.load(null); errdefer gl.glad.unload(); log.info("loaded OpenGL {}.{}", .{ gl.glad.versionMajor(@intCast(version)), gl.glad.versionMinor(@intCast(version)), }); }, apprt.glfw => try self.threadEnter(surface), } // These are very noisy so this is commented, but easy to uncomment // whenever we need to check the OpenGL extension list // if (builtin.mode == .Debug) { // var ext_iter = try gl.ext.iterator(); // while (try ext_iter.next()) |ext| { // log.debug("OpenGL extension available name={s}", .{ext}); // } // } } /// This is called just prior to spinning up the renderer thread for /// final main thread setup requirements. pub fn finalizeSurfaceInit(self: *const OpenGL, surface: *apprt.Surface) !void { _ = self; _ = surface; // For GLFW, we grabbed the OpenGL context in surfaceInit and we // need to release it before we start the renderer thread. if (apprt.runtime == apprt.glfw) { glfw.makeContextCurrent(null); } } /// Called when the OpenGL context is made invalid, so we need to free /// all previous resources and stop rendering. pub fn displayUnrealized(self: *OpenGL) void { if (single_threaded_draw) self.draw_mutex.lock(); defer if (single_threaded_draw) self.draw_mutex.unlock(); if (self.gl_state) |*v| { v.deinit(); self.gl_state = null; } } /// Called when the OpenGL is ready to be initialized. pub fn displayRealize(self: *OpenGL) !void { if (single_threaded_draw) self.draw_mutex.lock(); defer if (single_threaded_draw) self.draw_mutex.unlock(); // Reset our GPU uniforms const metrics = try resetFontMetrics( self.alloc, self.font_group, self.config.font_thicken, ); // Make our new state var gl_state = try GLState.init(self.font_group); errdefer gl_state.deinit(); // Unrealize if we have to if (self.gl_state) |*v| v.deinit(); // Set our new state self.gl_state = gl_state; // Make sure we invalidate all the fields so that we // reflush everything self.gl_cells_size = 0; self.gl_cells_written = 0; self.font_group.atlas_greyscale.modified = true; self.font_group.atlas_color.modified = true; // We need to reset our uniforms if (self.screen_size) |size| { self.deferred_screen_size = .{ .size = size }; } self.deferred_font_size = .{ .metrics = metrics }; } /// Callback called by renderer.Thread when it begins. pub fn threadEnter(self: *const OpenGL, surface: *apprt.Surface) !void { _ = self; switch (apprt.runtime) { else => @compileError("unsupported app runtime for OpenGL"), apprt.gtk => { // GTK doesn't support threaded OpenGL operations as far as I can // tell, so we use the renderer thread to setup all the state // but then do the actual draws and texture syncs and all that // on the main thread. As such, we don't do anything here. }, apprt.glfw => { // We need to make the OpenGL context current. OpenGL requires // that a single thread own the a single OpenGL context (if any). This // ensures that the context switches over to our thread. Important: // the prior thread MUST have detached the context prior to calling // this entrypoint. glfw.makeContextCurrent(surface.window); errdefer glfw.makeContextCurrent(null); glfw.swapInterval(1); // Load OpenGL bindings. This API is context-aware so this sets // a threadlocal context for these pointers. const version = try gl.glad.load(&glfw.getProcAddress); errdefer gl.glad.unload(); log.info("loaded OpenGL {}.{}", .{ gl.glad.versionMajor(@intCast(version)), gl.glad.versionMinor(@intCast(version)), }); }, } } /// Callback called by renderer.Thread when it exits. pub fn threadExit(self: *const OpenGL) void { _ = self; switch (apprt.runtime) { else => @compileError("unsupported app runtime for OpenGL"), apprt.gtk => { // We don't need to do any unloading for GTK because we may // be sharing the global bindings with other windows. }, apprt.glfw => { gl.glad.unload(); glfw.makeContextCurrent(null); }, } } /// Callback when the focus changes for the terminal this is rendering. /// /// Must be called on the render thread. pub fn setFocus(self: *OpenGL, focus: bool) !void { self.focused = focus; } /// Set the new font size. /// /// Must be called on the render thread. pub fn setFontSize(self: *OpenGL, size: font.face.DesiredSize) !void { if (single_threaded_draw) self.draw_mutex.lock(); defer if (single_threaded_draw) self.draw_mutex.unlock(); log.info("set font size={}", .{size}); // Set our new size, this will also reset our font atlas. try self.font_group.setSize(size); // Reset our GPU uniforms const metrics = try resetFontMetrics( self.alloc, self.font_group, self.config.font_thicken, ); // Defer our GPU updates self.deferred_font_size = .{ .metrics = metrics }; // Recalculate our cell size. If it is the same as before, then we do // nothing since the grid size couldn't have possibly changed. const new_cell_size = .{ .width = metrics.cell_width, .height = metrics.cell_height }; if (std.meta.eql(self.cell_size, new_cell_size)) return; self.cell_size = new_cell_size; // Notify the window that the cell size changed. _ = self.surface_mailbox.push(.{ .cell_size = new_cell_size, }, .{ .forever = {} }); } /// Reload the font metrics, recalculate cell size, and send that all /// down to the GPU. fn resetFontMetrics( alloc: Allocator, font_group: *font.GroupCache, font_thicken: bool, ) !font.face.Metrics { // Get our cell metrics based on a regular font ascii 'M'. Why 'M'? // Doesn't matter, any normal ASCII will do we're just trying to make // sure we use the regular font. const metrics = metrics: { const index = (try font_group.indexForCodepoint(alloc, 'M', .regular, .text)).?; const face = try font_group.group.faceFromIndex(index); break :metrics face.metrics; }; log.debug("cell dimensions={}", .{metrics}); // Set details for our sprite font font_group.group.sprite = font.sprite.Face{ .width = metrics.cell_width, .height = metrics.cell_height, .thickness = 2 * @as(u32, if (font_thicken) 2 else 1), .underline_position = metrics.underline_position, }; return metrics; } /// The primary render callback that is completely thread-safe. pub fn render( self: *OpenGL, surface: *apprt.Surface, state: *renderer.State, cursor_blink_visible: bool, ) !void { // Data we extract out of the critical area. const Critical = struct { gl_bg: terminal.color.RGB, selection: ?terminal.Selection, screen: terminal.Screen, preedit: ?renderer.State.Preedit, cursor_style: ?renderer.CursorStyle, }; // Update all our data as tightly as possible within the mutex. var critical: Critical = critical: { state.mutex.lock(); defer state.mutex.unlock(); // If we're in a synchronized output state, we pause all rendering. if (state.terminal.modes.get(.synchronized_output)) { log.debug("synchronized output started, skipping render", .{}); return; } // Swap bg/fg if the terminal is reversed const bg = self.config.background; const fg = self.config.foreground; defer { self.config.background = bg; self.config.foreground = fg; } if (state.terminal.modes.get(.reverse_colors)) { self.config.background = fg; self.config.foreground = bg; } // We used to share terminal state, but we've since learned through // analysis that it is faster to copy the terminal state than to // hold the lock wile rebuilding GPU cells. const viewport_bottom = state.terminal.screen.viewportIsBottom(); var screen_copy = if (viewport_bottom) try state.terminal.screen.clone( self.alloc, .{ .active = 0 }, .{ .active = state.terminal.rows - 1 }, ) else try state.terminal.screen.clone( self.alloc, .{ .viewport = 0 }, .{ .viewport = state.terminal.rows - 1 }, ); errdefer screen_copy.deinit(); // Convert our selection to viewport points because we copy only // the viewport above. const selection: ?terminal.Selection = if (state.terminal.screen.selection) |sel| sel.toViewport(&state.terminal.screen) else null; // Whether to draw our cursor or not. const cursor_style = renderer.cursorStyle( state, self.focused, cursor_blink_visible, ); break :critical .{ .gl_bg = self.config.background, .selection = selection, .screen = screen_copy, .preedit = if (cursor_style != null) state.preedit else null, .cursor_style = cursor_style, }; }; defer critical.screen.deinit(); // Grab our draw mutex if we have it and update our data { if (single_threaded_draw) self.draw_mutex.lock(); defer if (single_threaded_draw) self.draw_mutex.unlock(); // Set our draw data self.draw_background = critical.gl_bg; // Build our GPU cells try self.rebuildCells( critical.selection, &critical.screen, critical.preedit, critical.cursor_style, ); } // We're out of the critical path now. Let's render. We only render if // we're not single threaded. If we're single threaded we expect the // runtime to call draw. if (single_threaded_draw) return; try self.draw(); // Swap our window buffers switch (apprt.runtime) { else => @compileError("unsupported runtime"), apprt.glfw => surface.window.swapBuffers(), } } /// rebuildCells rebuilds all the GPU cells from our CPU state. This is a /// slow operation but ensures that the GPU state exactly matches the CPU state. /// In steady-state operation, we use some GPU tricks to send down stale data /// that is ignored. This accumulates more memory; rebuildCells clears it. /// /// Note this doesn't have to typically be manually called. Internally, /// the renderer will do this when it needs more memory space. pub fn rebuildCells( self: *OpenGL, term_selection: ?terminal.Selection, screen: *terminal.Screen, preedit: ?renderer.State.Preedit, cursor_style_: ?renderer.CursorStyle, ) !void { const t = trace(@src()); defer t.end(); // Bg cells at most will need space for the visible screen size self.cells_bg.clearRetainingCapacity(); try self.cells_bg.ensureTotalCapacity(self.alloc, screen.rows * screen.cols); // For now, we just ensure that we have enough cells for all the lines // we have plus a full width. This is very likely too much but its // the probably close enough while guaranteeing no more allocations. self.cells.clearRetainingCapacity(); try self.cells.ensureTotalCapacity( self.alloc, // * 3 for background modes and cursor and underlines // + 1 for cursor (screen.rows * screen.cols * 2) + 1, ); // We've written no data to the GPU, refresh it all self.gl_cells_written = 0; // This is the cell that has [mode == .fg] and is underneath our cursor. // We keep track of it so that we can invert the colors so the character // remains visible. var cursor_cell: ?GPUCell = null; // Build each cell var rowIter = screen.rowIterator(.viewport); var y: usize = 0; while (rowIter.next()) |row| { defer y += 1; // Our selection value is only non-null if this selection happens // to contain this row. This selection value will be set to only be // the selection that contains this row. This way, if the selection // changes but not for this line, we don't invalidate the cache. const selection = sel: { if (term_selection) |sel| { const screen_point = (terminal.point.Viewport{ .x = 0, .y = y, }).toScreen(screen); // If we are selected, we our colors are just inverted fg/bg. if (sel.containedRow(screen, screen_point)) |row_sel| { break :sel row_sel; } } break :sel null; }; // See Metal.zig const cursor_row = if (cursor_style_) |cursor_style| cursor_style == .block and screen.viewportIsBottom() and y == screen.cursor.y else false; // True if we want to do font shaping around the cursor. We want to // do font shaping as long as the cursor is enabled. const shape_cursor = screen.viewportIsBottom() and y == screen.cursor.y; // If this is the row with our cursor, then we may have to modify // the cell with the cursor. const start_i: usize = self.cells.items.len; defer if (cursor_row) { for (self.cells.items[start_i..]) |cell| { if (cell.grid_col == screen.cursor.x and cell.mode == .fg) { cursor_cell = cell; break; } } }; // Split our row into runs and shape each one. var iter = self.font_shaper.runIterator( self.font_group, row, selection, if (shape_cursor) screen.cursor.x else null, ); while (try iter.next(self.alloc)) |run| { for (try self.font_shaper.shape(run)) |shaper_cell| { if (self.updateCell( term_selection, screen, row.getCell(shaper_cell.x), shaper_cell, run, shaper_cell.x, y, )) |update| { assert(update); } else |err| { log.warn("error building cell, will be invalid x={} y={}, err={}", .{ shaper_cell.x, y, err, }); } } } // Set row is not dirty anymore row.setDirty(false); } // Add the cursor at the end so that it overlays everything. If we have // a cursor cell then we invert the colors on that and add it in so // that we can always see it. if (cursor_style_) |cursor_style| { const real_cursor_cell = self.addCursor(screen, cursor_style); // If we have a preedit, we try to render the preedit text on top // of the cursor. if (preedit) |preedit_v| preedit: { if (preedit_v.codepoint > 0) { // We try to base on the cursor cell but if its not there // we use the actual cursor and if thats not there we give // up on preedit rendering. var cell: GPUCell = cursor_cell orelse (real_cursor_cell orelse break :preedit).*; cell.fg_r = 0; cell.fg_g = 0; cell.fg_b = 0; cell.fg_a = 255; // If preedit rendering succeeded then we don't want to // re-render the underlying cell fg if (self.updateCellChar(&cell, preedit_v.codepoint)) { cursor_cell = null; self.cells.appendAssumeCapacity(cell); } } } if (cursor_cell) |*cell| { if (self.config.cursor_text) |txt| { cell.fg_r = txt.r; cell.fg_g = txt.g; cell.fg_b = txt.b; cell.fg_a = 255; } else { cell.fg_r = 0; cell.fg_g = 0; cell.fg_b = 0; cell.fg_a = 255; } self.cells.appendAssumeCapacity(cell.*); } } // Some debug mode safety checks if (std.debug.runtime_safety) { for (self.cells_bg.items) |cell| assert(cell.mode == .bg); for (self.cells.items) |cell| assert(cell.mode != .bg); } } fn addCursor( self: *OpenGL, screen: *terminal.Screen, cursor_style: renderer.CursorStyle, ) ?*const GPUCell { // Add the cursor const cell = screen.getCell( .active, screen.cursor.y, screen.cursor.x, ); const color = self.config.cursor_color orelse terminal.color.RGB{ .r = 0xFF, .g = 0xFF, .b = 0xFF, }; const sprite: font.Sprite = switch (cursor_style) { .block => .cursor_rect, .block_hollow => .cursor_hollow_rect, .bar => .cursor_bar, .underline => .underline, }; const glyph = self.font_group.renderGlyph( self.alloc, font.sprite_index, @intFromEnum(sprite), .{}, ) catch |err| { log.warn("error rendering cursor glyph err={}", .{err}); return null; }; self.cells.appendAssumeCapacity(.{ .mode = .fg, .grid_col = @intCast(screen.cursor.x), .grid_row = @intCast(screen.cursor.y), .grid_width = if (cell.attrs.wide) 2 else 1, .fg_r = color.r, .fg_g = color.g, .fg_b = color.b, .fg_a = 255, .bg_r = 0, .bg_g = 0, .bg_b = 0, .bg_a = 0, .glyph_x = glyph.atlas_x, .glyph_y = glyph.atlas_y, .glyph_width = glyph.width, .glyph_height = glyph.height, .glyph_offset_x = glyph.offset_x, .glyph_offset_y = glyph.offset_y, }); return &self.cells.items[self.cells.items.len - 1]; } /// Updates cell with the the given character. This returns true if the /// cell was successfully updated. fn updateCellChar(self: *OpenGL, cell: *GPUCell, cp: u21) bool { // Get the font index for this codepoint const font_index = if (self.font_group.indexForCodepoint( self.alloc, @intCast(cp), .regular, .text, )) |index| index orelse return false else |_| return false; // Get the font face so we can get the glyph const face = self.font_group.group.faceFromIndex(font_index) catch |err| { log.warn("error getting face for font_index={} err={}", .{ font_index, err }); return false; }; // Use the face to now get the glyph index const glyph_index = face.glyphIndex(@intCast(cp)) orelse return false; // Render the glyph for our preedit text const glyph = self.font_group.renderGlyph( self.alloc, font_index, glyph_index, .{}, ) catch |err| { log.warn("error rendering preedit glyph err={}", .{err}); return false; }; // Update the cell glyph cell.glyph_x = glyph.atlas_x; cell.glyph_y = glyph.atlas_y; cell.glyph_width = glyph.width; cell.glyph_height = glyph.height; cell.glyph_offset_x = glyph.offset_x; cell.glyph_offset_y = glyph.offset_y; return true; } /// Update a single cell. The bool returns whether the cell was updated /// or not. If the cell wasn't updated, a full refreshCells call is /// needed. pub fn updateCell( self: *OpenGL, selection: ?terminal.Selection, screen: *terminal.Screen, cell: terminal.Screen.Cell, shaper_cell: font.shape.Cell, shaper_run: font.shape.TextRun, x: usize, y: usize, ) !bool { const t = trace(@src()); defer t.end(); const BgFg = struct { /// Background is optional because in un-inverted mode /// it may just be equivalent to the default background in /// which case we do nothing to save on GPU render time. bg: ?terminal.color.RGB, /// Fg is always set to some color, though we may not render /// any fg if the cell is empty or has no attributes like /// underline. fg: terminal.color.RGB, }; // True if this cell is selected // TODO(perf): we can check in advance if selection is in // our viewport at all and not run this on every point. const selected: bool = if (selection) |sel| selected: { const screen_point = (terminal.point.Viewport{ .x = x, .y = y, }).toScreen(screen); break :selected sel.contains(screen_point); } else false; // The colors for the cell. const colors: BgFg = colors: { // If we are selected, we our colors are just inverted fg/bg var selection_res: ?BgFg = if (selected) .{ .bg = self.config.selection_background orelse self.config.foreground, .fg = self.config.selection_foreground orelse self.config.background, } else null; const res: BgFg = selection_res orelse if (!cell.attrs.inverse) .{ // In normal mode, background and fg match the cell. We // un-optionalize the fg by defaulting to our fg color. .bg = if (cell.attrs.has_bg) cell.bg else null, .fg = if (cell.attrs.has_fg) cell.fg else self.config.foreground, } else .{ // In inverted mode, the background MUST be set to something // (is never null) so it is either the fg or default fg. The // fg is either the bg or default background. .bg = if (cell.attrs.has_fg) cell.fg else self.config.foreground, .fg = if (cell.attrs.has_bg) cell.bg else self.config.background, }; // If the cell is "invisible" then we just make fg = bg so that // the cell is transparent but still copy-able. if (cell.attrs.invisible) { break :colors BgFg{ .bg = res.bg, .fg = res.bg orelse self.config.background, }; } break :colors res; }; // Calculate the amount of space we need in the cells list. const needed = needed: { var i: usize = 0; if (colors.bg != null) i += 1; if (!cell.empty()) i += 1; if (cell.attrs.underline != .none) i += 1; if (cell.attrs.strikethrough) i += 1; break :needed i; }; if (self.cells.items.len + needed > self.cells.capacity) return false; // Alpha multiplier const alpha: u8 = if (cell.attrs.faint) 175 else 255; // If the cell has a background, we always draw it. if (colors.bg) |rgb| { // Determine our background alpha. If we have transparency configured // then this is dynamic depending on some situations. This is all // in an attempt to make transparency look the best for various // situations. See inline comments. const bg_alpha: u8 = bg_alpha: { if (self.config.background_opacity >= 1) break :bg_alpha alpha; // If we're selected, we do not apply background opacity if (selected) break :bg_alpha alpha; // If we're reversed, do not apply background opacity if (cell.attrs.inverse) break :bg_alpha alpha; // If we have a background and its not the default background // then we apply background opacity if (cell.attrs.has_bg and !std.meta.eql(rgb, self.config.background)) { break :bg_alpha alpha; } // We apply background opacity. var bg_alpha: f64 = @floatFromInt(alpha); bg_alpha *= self.config.background_opacity; bg_alpha = @ceil(bg_alpha); break :bg_alpha @intFromFloat(bg_alpha); }; self.cells_bg.appendAssumeCapacity(.{ .mode = .bg, .grid_col = @intCast(x), .grid_row = @intCast(y), .grid_width = cell.widthLegacy(), .glyph_x = 0, .glyph_y = 0, .glyph_width = 0, .glyph_height = 0, .glyph_offset_x = 0, .glyph_offset_y = 0, .fg_r = 0, .fg_g = 0, .fg_b = 0, .fg_a = 0, .bg_r = rgb.r, .bg_g = rgb.g, .bg_b = rgb.b, .bg_a = bg_alpha, }); } // If the cell has a character, draw it if (cell.char > 0) { // Render const glyph = try self.font_group.renderGlyph( self.alloc, shaper_run.font_index, shaper_cell.glyph_index, .{ .max_height = @intCast(self.cell_size.height), .thicken = self.config.font_thicken, }, ); // If we're rendering a color font, we use the color atlas const presentation = try self.font_group.group.presentationFromIndex(shaper_run.font_index); const mode: GPUCellMode = switch (presentation) { .text => .fg, .emoji => .fg_color, }; self.cells.appendAssumeCapacity(.{ .mode = mode, .grid_col = @intCast(x), .grid_row = @intCast(y), .grid_width = cell.widthLegacy(), .glyph_x = glyph.atlas_x, .glyph_y = glyph.atlas_y, .glyph_width = glyph.width, .glyph_height = glyph.height, .glyph_offset_x = glyph.offset_x, .glyph_offset_y = glyph.offset_y, .fg_r = colors.fg.r, .fg_g = colors.fg.g, .fg_b = colors.fg.b, .fg_a = alpha, .bg_r = 0, .bg_g = 0, .bg_b = 0, .bg_a = 0, }); } if (cell.attrs.underline != .none) { const sprite: font.Sprite = switch (cell.attrs.underline) { .none => unreachable, .single => .underline, .double => .underline_double, .dotted => .underline_dotted, .dashed => .underline_dashed, .curly => .underline_curly, }; const underline_glyph = try self.font_group.renderGlyph( self.alloc, font.sprite_index, @intFromEnum(sprite), .{}, ); const color = if (cell.attrs.underline_color) cell.underline_fg else colors.fg; self.cells.appendAssumeCapacity(.{ .mode = .fg, .grid_col = @intCast(x), .grid_row = @intCast(y), .grid_width = cell.widthLegacy(), .glyph_x = underline_glyph.atlas_x, .glyph_y = underline_glyph.atlas_y, .glyph_width = underline_glyph.width, .glyph_height = underline_glyph.height, .glyph_offset_x = underline_glyph.offset_x, .glyph_offset_y = underline_glyph.offset_y, .fg_r = color.r, .fg_g = color.g, .fg_b = color.b, .fg_a = alpha, .bg_r = 0, .bg_g = 0, .bg_b = 0, .bg_a = 0, }); } if (cell.attrs.strikethrough) { self.cells.appendAssumeCapacity(.{ .mode = .strikethrough, .grid_col = @intCast(x), .grid_row = @intCast(y), .grid_width = cell.widthLegacy(), .glyph_x = 0, .glyph_y = 0, .glyph_width = 0, .glyph_height = 0, .glyph_offset_x = 0, .glyph_offset_y = 0, .fg_r = colors.fg.r, .fg_g = colors.fg.g, .fg_b = colors.fg.b, .fg_a = alpha, .bg_r = 0, .bg_g = 0, .bg_b = 0, .bg_a = 0, }); } return true; } /// Returns the grid size for a given screen size. This is safe to call /// on any thread. fn gridSize(self: *const OpenGL, screen_size: renderer.ScreenSize) renderer.GridSize { return renderer.GridSize.init( screen_size.subPadding(self.padding.explicit), self.cell_size, ); } /// Update the configuration. pub fn changeConfig(self: *OpenGL, config: *DerivedConfig) !void { // On configuration change we always reset our font group. There // are a variety of configurations that can change font settings // so to be safe we just always reset it. This has a performance hit // when its not necessary but config reloading shouldn't be so // common to cause a problem. self.font_group.reset(); self.font_group.group.styles = config.font_styles; self.font_group.atlas_greyscale.clear(); self.font_group.atlas_color.clear(); // We always redo the font shaper in case font features changed. We // could check to see if there was an actual config change but this is // easier and rare enough to not cause performance issues. { var font_shaper = try font.Shaper.init(self.alloc, .{ .features = config.font_features.items, }); errdefer font_shaper.deinit(); self.font_shaper.deinit(); self.font_shaper = font_shaper; } self.config.deinit(); self.config = config.*; } /// Set the screen size for rendering. This will update the projection /// used for the shader so that the scaling of the grid is correct. pub fn setScreenSize( self: *OpenGL, dim: renderer.ScreenSize, pad: renderer.Padding, ) !void { if (single_threaded_draw) self.draw_mutex.lock(); defer if (single_threaded_draw) self.draw_mutex.unlock(); // Store our screen size self.screen_size = dim; self.padding.explicit = pad; // Recalculate the rows/columns. const grid_size = self.gridSize(dim); log.debug("screen size screen={} grid={} cell={} padding={}", .{ dim, grid_size, self.cell_size, self.padding.explicit, }); // Defer our OpenGL updates self.deferred_screen_size = .{ .size = dim }; } /// Updates the font texture atlas if it is dirty. fn flushAtlas(self: *OpenGL) !void { const gl_state = self.gl_state orelse return; { const atlas = &self.font_group.atlas_greyscale; if (atlas.modified) { atlas.modified = false; var texbind = try gl_state.texture.bind(.@"2D"); defer texbind.unbind(); if (atlas.resized) { atlas.resized = false; try texbind.image2D( 0, .Red, @intCast(atlas.size), @intCast(atlas.size), 0, .Red, .UnsignedByte, atlas.data.ptr, ); } else { try texbind.subImage2D( 0, 0, 0, @intCast(atlas.size), @intCast(atlas.size), .Red, .UnsignedByte, atlas.data.ptr, ); } } } { const atlas = &self.font_group.atlas_color; if (atlas.modified) { atlas.modified = false; var texbind = try gl_state.texture_color.bind(.@"2D"); defer texbind.unbind(); if (atlas.resized) { atlas.resized = false; try texbind.image2D( 0, .RGBA, @intCast(atlas.size), @intCast(atlas.size), 0, .BGRA, .UnsignedByte, atlas.data.ptr, ); } else { try texbind.subImage2D( 0, 0, 0, @intCast(atlas.size), @intCast(atlas.size), .BGRA, .UnsignedByte, atlas.data.ptr, ); } } } } /// Render renders the current cell state. This will not modify any of /// the cells. pub fn draw(self: *OpenGL) !void { const t = trace(@src()); defer t.end(); // If we're in single-threaded more we grab a lock since we use shared data. if (single_threaded_draw) self.draw_mutex.lock(); defer if (single_threaded_draw) self.draw_mutex.unlock(); const gl_state = self.gl_state orelse return; // Try to flush our atlas, this will only do something if there // are changes to the atlas. try self.flushAtlas(); // Clear the surface gl.clearColor( @as(f32, @floatFromInt(self.draw_background.r)) / 255, @as(f32, @floatFromInt(self.draw_background.g)) / 255, @as(f32, @floatFromInt(self.draw_background.b)) / 255, @floatCast(self.config.background_opacity), ); gl.clear(gl.c.GL_COLOR_BUFFER_BIT); // Setup our VAO try gl_state.vao.bind(); defer gl.VertexArray.unbind() catch null; // Bind EBO var ebobind = try gl_state.ebo.bind(.ElementArrayBuffer); defer ebobind.unbind(); // Bind VBO and set data var binding = try gl_state.vbo.bind(.ArrayBuffer); defer binding.unbind(); // Bind our textures try gl.Texture.active(gl.c.GL_TEXTURE0); var texbind = try gl_state.texture.bind(.@"2D"); defer texbind.unbind(); try gl.Texture.active(gl.c.GL_TEXTURE1); var texbind1 = try gl_state.texture_color.bind(.@"2D"); defer texbind1.unbind(); // Pick our shader to use const pbind = try gl_state.program.use(); defer pbind.unbind(); // If we have deferred operations, run them. if (self.deferred_screen_size) |v| { try v.apply(self); self.deferred_screen_size = null; } if (self.deferred_font_size) |v| { try v.apply(self); self.deferred_font_size = null; } try self.drawCells(binding, self.cells_bg); try self.drawCells(binding, self.cells); } /// Loads some set of cell data into our buffer and issues a draw call. /// This expects all the OpenGL state to be setup. /// /// Future: when we move to multiple shaders, this will go away and /// we'll have a draw call per-shader. fn drawCells( self: *OpenGL, binding: gl.Buffer.Binding, cells: std.ArrayListUnmanaged(GPUCell), ) !void { // If we have no cells to render, then we render nothing. if (cells.items.len == 0) return; // Todo: get rid of this completely self.gl_cells_written = 0; // Our allocated buffer on the GPU is smaller than our capacity. // We reallocate a new buffer with the full new capacity. if (self.gl_cells_size < cells.capacity) { log.info("reallocating GPU buffer old={} new={}", .{ self.gl_cells_size, cells.capacity, }); try binding.setDataNullManual( @sizeOf(GPUCell) * cells.capacity, .StaticDraw, ); self.gl_cells_size = cells.capacity; self.gl_cells_written = 0; } // If we have data to write to the GPU, send it. if (self.gl_cells_written < cells.items.len) { const data = cells.items[self.gl_cells_written..]; // log.info("sending {} cells to GPU", .{data.len}); try binding.setSubData(self.gl_cells_written * @sizeOf(GPUCell), data); self.gl_cells_written += data.len; assert(data.len > 0); assert(self.gl_cells_written <= cells.items.len); } try gl.drawElementsInstanced( gl.c.GL_TRIANGLES, 6, gl.c.GL_UNSIGNED_BYTE, cells.items.len, ); } /// The OpenGL objects that are associated with a renderer. This makes it /// easy to create/destroy these as a set in situations i.e. where the /// OpenGL context is replaced. const GLState = struct { program: gl.Program, vao: gl.VertexArray, ebo: gl.Buffer, vbo: gl.Buffer, texture: gl.Texture, texture_color: gl.Texture, pub fn init(font_group: *font.GroupCache) !GLState { // Blending for text. We use GL_ONE here because we should be using // premultiplied alpha for all our colors in our fragment shaders. // This avoids having a blurry border where transparency is expected on // pixels. try gl.enable(gl.c.GL_BLEND); try gl.blendFunc(gl.c.GL_ONE, gl.c.GL_ONE_MINUS_SRC_ALPHA); // Shader const program = try gl.Program.createVF( @embedFile("shaders/cell.v.glsl"), @embedFile("shaders/cell.f.glsl"), ); // Set our cell dimensions const pbind = try program.use(); defer pbind.unbind(); // Set all of our texture indexes try program.setUniform("text", 0); try program.setUniform("text_color", 1); // Setup our VAO const vao = try gl.VertexArray.create(); errdefer vao.destroy(); try vao.bind(); defer gl.VertexArray.unbind() catch null; // Element buffer (EBO) const ebo = try gl.Buffer.create(); errdefer ebo.destroy(); var ebobind = try ebo.bind(.ElementArrayBuffer); defer ebobind.unbind(); try ebobind.setData([6]u8{ 0, 1, 3, // Top-left triangle 1, 2, 3, // Bottom-right triangle }, .StaticDraw); // Vertex buffer (VBO) const vbo = try gl.Buffer.create(); errdefer vbo.destroy(); var vbobind = try vbo.bind(.ArrayBuffer); defer vbobind.unbind(); var offset: usize = 0; try vbobind.attributeAdvanced(0, 2, gl.c.GL_UNSIGNED_SHORT, false, @sizeOf(GPUCell), offset); offset += 2 * @sizeOf(u16); try vbobind.attributeAdvanced(1, 2, gl.c.GL_UNSIGNED_INT, false, @sizeOf(GPUCell), offset); offset += 2 * @sizeOf(u32); try vbobind.attributeAdvanced(2, 2, gl.c.GL_UNSIGNED_INT, false, @sizeOf(GPUCell), offset); offset += 2 * @sizeOf(u32); try vbobind.attributeAdvanced(3, 2, gl.c.GL_INT, false, @sizeOf(GPUCell), offset); offset += 2 * @sizeOf(i32); try vbobind.attributeAdvanced(4, 4, gl.c.GL_UNSIGNED_BYTE, false, @sizeOf(GPUCell), offset); offset += 4 * @sizeOf(u8); try vbobind.attributeAdvanced(5, 4, gl.c.GL_UNSIGNED_BYTE, false, @sizeOf(GPUCell), offset); offset += 4 * @sizeOf(u8); try vbobind.attributeIAdvanced(6, 1, gl.c.GL_UNSIGNED_BYTE, @sizeOf(GPUCell), offset); offset += 1 * @sizeOf(u8); try vbobind.attributeIAdvanced(7, 1, gl.c.GL_UNSIGNED_BYTE, @sizeOf(GPUCell), offset); try vbobind.enableAttribArray(0); try vbobind.enableAttribArray(1); try vbobind.enableAttribArray(2); try vbobind.enableAttribArray(3); try vbobind.enableAttribArray(4); try vbobind.enableAttribArray(5); try vbobind.enableAttribArray(6); try vbobind.enableAttribArray(7); try vbobind.attributeDivisor(0, 1); try vbobind.attributeDivisor(1, 1); try vbobind.attributeDivisor(2, 1); try vbobind.attributeDivisor(3, 1); try vbobind.attributeDivisor(4, 1); try vbobind.attributeDivisor(5, 1); try vbobind.attributeDivisor(6, 1); try vbobind.attributeDivisor(7, 1); // Build our texture const tex = try gl.Texture.create(); errdefer tex.destroy(); { const texbind = try tex.bind(.@"2D"); try texbind.parameter(.WrapS, gl.c.GL_CLAMP_TO_EDGE); try texbind.parameter(.WrapT, gl.c.GL_CLAMP_TO_EDGE); try texbind.parameter(.MinFilter, gl.c.GL_LINEAR); try texbind.parameter(.MagFilter, gl.c.GL_LINEAR); try texbind.image2D( 0, .Red, @intCast(font_group.atlas_greyscale.size), @intCast(font_group.atlas_greyscale.size), 0, .Red, .UnsignedByte, font_group.atlas_greyscale.data.ptr, ); } // Build our color texture const tex_color = try gl.Texture.create(); errdefer tex_color.destroy(); { const texbind = try tex_color.bind(.@"2D"); try texbind.parameter(.WrapS, gl.c.GL_CLAMP_TO_EDGE); try texbind.parameter(.WrapT, gl.c.GL_CLAMP_TO_EDGE); try texbind.parameter(.MinFilter, gl.c.GL_LINEAR); try texbind.parameter(.MagFilter, gl.c.GL_LINEAR); try texbind.image2D( 0, .RGBA, @intCast(font_group.atlas_color.size), @intCast(font_group.atlas_color.size), 0, .BGRA, .UnsignedByte, font_group.atlas_color.data.ptr, ); } return .{ .program = program, .vao = vao, .ebo = ebo, .vbo = vbo, .texture = tex, .texture_color = tex_color, }; } pub fn deinit(self: *GLState) void { self.texture.destroy(); self.texture_color.destroy(); self.vbo.destroy(); self.ebo.destroy(); self.vao.destroy(); self.program.destroy(); } };