perf(@typegpu/gl): cache linked programs per root

packages/typegpu-gl/src/tgpuRootWebGL.ts

@@ -106,25 +106,29 @@ function linkProgram(
   fragSource: string,
 ): WebGLProgram {
   const vert = compileShader(gl, gl.VERTEX_SHADER, vertSource);
-  const frag = compileShader(gl, gl.FRAGMENT_SHADER, fragSource);
+  let frag: WebGLShader | undefined;
 
-  const program = gl.createProgram();
-  if (!program) throw new Error('Failed to create WebGL program');
+  try {
+    frag = compileShader(gl, gl.FRAGMENT_SHADER, fragSource);
 
-  gl.attachShader(program, vert);
-  gl.attachShader(program, frag);
-  gl.linkProgram(program);
+    const program = gl.createProgram();
+    if (!program) throw new Error('Failed to create WebGL program');
 
-  gl.deleteShader(vert);
-  gl.deleteShader(frag);
+    gl.attachShader(program, vert);
+    gl.attachShader(program, frag);
+    gl.linkProgram(program);
 
-  if (!gl.getProgramParameter(program, gl.LINK_STATUS)) {
-    const log = gl.getProgramInfoLog(program);
-    gl.deleteProgram(program);
-    throw new Error(`Program linking failed: ${log}`);
-  }
+    if (!gl.getProgramParameter(program, gl.LINK_STATUS)) {
+      const log = gl.getProgramInfoLog(program);
+      gl.deleteProgram(program);
+      throw new Error(`Program linking failed: ${log}`);
+    }
 
-  return program;
+    return program;
+  } finally {
+    gl.deleteShader(vert);
+    if (frag) gl.deleteShader(frag);
+  }
 }
 
 interface UniformBinding {
@@ -406,6 +410,7 @@ export class TgpuRootWebGL {
   #buffers: WebGLBuffer[] = [];
   #textures: WebGLTextureImpl[] = [];
   #samplers: WebGLSamplerImpl[] = [];
+  #programCache = new Map<string, WebGLProgram>();
 
   constructor(gl: WebGL2RenderingContext) {
     this.#gl = gl;
@@ -513,7 +518,12 @@ export class TgpuRootWebGL {
     const vertexGlsl = GLSL_HEADER + vertexCode;
     const fragmentGlsl = GLSL_HEADER + fragmentCode;
 
-    const program = linkProgram(this.#gl, vertexGlsl, fragmentGlsl);
+    const key = vertexGlsl + '\0' + fragmentGlsl;
+    let program = this.#programCache.get(key);
+    if (!program) {
+      program = linkProgram(this.#gl, vertexGlsl, fragmentGlsl);
+      this.#programCache.set(key, program);
+    }
 
     return new TgpuWebGLRenderPipelineImpl(
       this.#gl,
@@ -545,6 +555,10 @@ export class TgpuRootWebGL {
   }
 
   destroy(): void {
+    for (const program of this.#programCache.values()) {
+      this.#gl.deleteProgram(program);
+    }
+    this.#programCache.clear();
     for (const buf of this.#buffers) {
       this.#gl.deleteBuffer(buf);
     }