From c6a5aaf5c4a020eaefe24943ecb6cf9d4eb26836 Mon Sep 17 00:00:00 2001 From: Gabriel Schneider Date: Mon, 28 Sep 2026 15:57:22 -0300 Subject: Post chain: Shadertoy passes compiled by glslc; Crt, Ripple and Glitch rewritten as Shadertoy files Stage 9 of docs/render-pipeline.md. src/gui/Post.zig runs the chain over the finished frame: each pass reads the one before, ping-pong textures between, the last writes the window; an empty chain is the direct path. The prefix (shaders/post/prefix.glsl) is ghostty's uniform block, name for name and offset for offset (tested against a copy of its Uniforms, the selection colours by their GLSL names), at SDL GPU's bindings, y down. A user's file (Shader ) is compiled by glslc with compileGlsl's own flags on a thread of its own, taken in at the next loop step; errors name the file's own lines; a failed compile keeps the last good pipeline; glslc missing is said once. The bundled passes compile with the build, through the same prefix. Crt, Ripple and Glitch are Shadertoy files, rewritten: no barrel (input is identity, tested), everything in linear light and dithered, keyed to iTime. scene_effects, crt.zig and crt.frag.glsl are gone; the core keeps no clock for the chain. ShaderAnimation off|on|always drives redraw level A: the chain alone over the retained frame (34 us CPU a redraw, measured). Shared files touched: pardes.zig (nextWake loses the scene line, disableSceneEffects empties the chain, two tests), builtins.zig (one switch arm), ninep/ctl.zig (two switch arms), macos.zig (flags from the chain), gui.zig. Not touched: Messages.zig, mouse.zig, detached/*, host_io, tty. --- shaders/post/prefix.glsl | 67 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 67 insertions(+) create mode 100644 shaders/post/prefix.glsl (limited to 'shaders/post/prefix.glsl') diff --git a/shaders/post/prefix.glsl b/shaders/post/prefix.glsl new file mode 100644 index 00000000..efa49483 --- /dev/null +++ b/shaders/post/prefix.glsl @@ -0,0 +1,67 @@ +#version 450 +// pardes's Shadertoy prefix (docs/render-pipeline.md ยง6), put before every +// post pass: a bundled one in shaders/post/ at build time, a user's file at +// run time. The uniform names, types and std140 order are ghostty 1.3.2's +// (src/renderer/shaders/shadertoy_prefix.glsl), so a shader written for +// ghostty runs here; only the bindings are SDL GPU's (a fragment shader's +// textures in set 2, its uniform blocks in set 3). Y is down everywhere, as +// on ghostty's Metal renderer: fragCoord, iChannel0's uv and the cursor +// rectangles share one top-left space, and iCurrentCursor is (left x, +// BOTTOM-edge y, width, height) in framebuffer pixels. + +layout(set = 3, binding = 0, std140) uniform Globals { + uniform vec3 iResolution; + uniform float iTime; + uniform float iTimeDelta; + uniform float iFrameRate; + uniform int iFrame; + uniform float iChannelTime[4]; + uniform vec3 iChannelResolution[4]; + uniform vec4 iMouse; + uniform vec4 iDate; + uniform float iSampleRate; + uniform vec4 iCurrentCursor; + uniform vec4 iPreviousCursor; + uniform vec4 iCurrentCursorColor; + uniform vec4 iPreviousCursorColor; + uniform int iCurrentCursorStyle; + uniform int iPreviousCursorStyle; + uniform int iCursorVisible; + uniform float iTimeCursorChange; + uniform float iTimeFocus; + uniform int iFocus; + uniform vec3 iPalette[256]; + uniform vec3 iBackgroundColor; + uniform vec3 iForegroundColor; + uniform vec3 iCursorColor; + uniform vec3 iCursorText; + uniform vec3 iSelectionForegroundColor; + uniform vec3 iSelectionBackgroundColor; +}; + +// pardes's own: 1 when the window is opaque, so a pass cannot punch holes +// in it through its alpha. +layout(set = 3, binding = 1, std140) uniform PardesPost { + float pardesOpaque; +}; + +#define CURSORSTYLE_BLOCK 0 +#define CURSORSTYLE_BLOCK_HOLLOW 1 +#define CURSORSTYLE_BAR 2 +#define CURSORSTYLE_UNDERLINE 3 +#define CURSORSTYLE_LOCK 4 + +layout(set = 2, binding = 0) uniform sampler2D iChannel0; + +layout(location = 0) out vec4 _fragColor; + +#define texture2D texture + +void mainImage(out vec4 fragColor, in vec2 fragCoord); +void main() { + mainImage(_fragColor, gl_FragCoord.xy); + if (pardesOpaque > 0.5) _fragColor.a = 1.0; +} + +// The shader's own lines count from 1, so glslc's errors name them. +#line 1 -- cgit v1.3