Add WebGL compatibility

src/drawables/drawable-descriptor.ts

@@ -1,7 +1,7 @@
 import { Drawable } from './drawable';
 
 export interface DrawableDescriptor {
-  uniformName: string;
+  propertyUniformMapping: { [property: string]: string };
   uniformCountMacroName: string;
   sdf?: {
     shader: string;

src/drawables/drawable.ts

@@ -6,7 +6,6 @@ export abstract class Drawable {
   public static readonly descriptor: DrawableDescriptor;
 
   public abstract minDistance(target: vec2): number;
-
   protected abstract getObjectToSerialize(transform2d: mat2d, transform1d: number): any;
 
   public serializeToUniforms(
@@ -14,12 +13,15 @@ export abstract class Drawable {
     transform2d: mat2d,
     transform1d: number
   ): void {
-    const { uniformName } = (this.constructor as typeof Drawable).descriptor;
+    const { propertyUniformMapping } = (this.constructor as typeof Drawable).descriptor;
 
-    if (!Object.prototype.hasOwnProperty.call(uniforms, uniformName)) {
-      uniforms[uniformName] = [];
-    }
+    const serialized = this.getObjectToSerialize(transform2d, transform1d);
+    Object.entries(propertyUniformMapping).forEach(([k, v]) => {
+      if (!Object.prototype.hasOwnProperty.call(uniforms, v)) {
+        uniforms[v] = [];
+      }
 
-    uniforms[uniformName].push(this.getObjectToSerialize(transform2d, transform1d));
+      uniforms[v].push(serialized[k]);
+    });
   }
 }

src/drawables/lights/circle-light.ts

@@ -4,9 +4,13 @@ import { LightDrawable } from './light-drawable';
 
 export class CircleLight extends LightDrawable {
   public static readonly descriptor: DrawableDescriptor = {
-    uniformName: 'circleLights',
+    propertyUniformMapping: {
+      center: 'circleLightCenters',
+      color: 'circleLightColors',
+      intensity: 'circleLightIntensities',
+    },
     uniformCountMacroName: 'CIRCLE_LIGHT_COUNT',
-    shaderCombinationSteps: [0, 1, 2, 4, 8],
+    shaderCombinationSteps: [0, 1, 2, 4, 8, 16],
     empty: new CircleLight(vec2.fromValues(0, 0), vec3.fromValues(0, 0, 0), 0),
   };
 

src/drawables/lights/flashlight.ts

@@ -4,7 +4,12 @@ import { LightDrawable } from './light-drawable';
 
 export class Flashlight extends LightDrawable {
   public static readonly descriptor: DrawableDescriptor = {
-    uniformName: 'flashlights',
+    propertyUniformMapping: {
+      center: 'flashlightCenters',
+      color: 'flashlightColors',
+      intensity: 'flashlightIntensities',
+      direction: 'flashlightDirections',
+    },
     uniformCountMacroName: 'FLASHLIGHT_COUNT',
     shaderCombinationSteps: [0, 1, 2, 4],
     empty: new Flashlight(

src/drawables/shapes/circle.ts

@@ -6,15 +6,13 @@ export class Circle extends Drawable {
   public static descriptor: DrawableDescriptor = {
     sdf: {
       shader: `
-          uniform struct {
-              vec2 center;
-              float radius;
-          }[CIRCLE_COUNT] circles;
+          uniform vec2 circleCenters[CIRCLE_COUNT];
+          uniform vec2 circleRadii[CIRCLE_COUNT];
 
           void circleMinDistance(inout float minDistance, inout float color) {
               float myMinDistance = maxMinDistance;
               for (int i = 0; i < CIRCLE_COUNT; i++) {
-                  float dist = distance(circles[i].center, position) - circles[i].radius;
+                  float dist = distance(circleCenters[i], position) - circleRadii[i];
                   myMinDistance = min(myMinDistance, dist);
               }
               minDistance = min(minDistance, myMinDistance);
@@ -26,9 +24,12 @@ export class Circle extends Drawable {
         `,
       distanceFunctionName: 'circleMinDistance',
     },
-    uniformName: 'circles',
+    propertyUniformMapping: {
+      center: 'circleCenters',
+      radius: 'circleRadii',
+    },
     uniformCountMacroName: 'CIRCLE_COUNT',
-    shaderCombinationSteps: [0, 1, 2, 3, 16, 32],
+    shaderCombinationSteps: [0, 1, 2, 3, 8, 16],
     empty: new Circle(vec2.fromValues(0, 0), 0),
   };
 

src/drawables/shapes/inverted-tunnel.ts

@@ -8,44 +8,46 @@ export class InvertedTunnel extends Drawable {
   public static descriptor: DrawableDescriptor = {
     sdf: {
       shader: `
-          uniform struct InvertedTunnel {
-            vec2 from;
-            vec2 toFromDelta;
-            float fromRadius;
-            float toRadius;
-          }[INVERTED_TUNNEL_COUNT] invertedTunnels;
+        uniform vec2 froms[INVERTED_TUNNEL_COUNT];
+        uniform vec2 toFromDeltas[INVERTED_TUNNEL_COUNT];
+        uniform float fromRadii[INVERTED_TUNNEL_COUNT];
+        uniform float toRadii[INVERTED_TUNNEL_COUNT];
       
-          void invertedTunnelMinDistance(inout float minDistance, inout float color) {
-            float myMinDistance = -minDistance;
-            for (int i = 0; i < INVERTED_TUNNEL_COUNT; i++) {
-              InvertedTunnel tunnel = invertedTunnels[i];
-              vec2 targetFromDelta = position - tunnel.from;
+        void invertedTunnelMinDistance(inout float minDistance, inout float color) {
+          float myMinDistance = -minDistance;
+          for (int i = 0; i < INVERTED_TUNNEL_COUNT; i++) {
+            vec2 targetFromDelta = position - froms[i];
             
-              float h = clamp(
-                  dot(targetFromDelta, tunnel.toFromDelta)
-                / dot(tunnel.toFromDelta, tunnel.toFromDelta),
-                0.0, 1.0
-              );
+            float h = clamp(
+                dot(targetFromDelta, toFromDeltas[i])
+              / dot(toFromDeltas[i], toFromDeltas[i]),
+              0.0, 1.0
+            );
 
-              float currentDistance = -mix(
-                tunnel.fromRadius, tunnel.toRadius, h
-              ) + distance(
-                targetFromDelta, tunnel.toFromDelta * h
-              );
+            float currentDistance = -mix(
+              fromRadii[i], toRadii[i], h
+            ) + distance(
+              targetFromDelta, toFromDeltas[i] * h
+            );
 
-              myMinDistance = min(myMinDistance, currentDistance);
-            }
-    
-            color = mix(0.0, color, step(
-              distanceNdcPixelSize + SURFACE_OFFSET,
-              -myMinDistance
-            ));
-            minDistance = -myMinDistance;
+            myMinDistance = min(myMinDistance, currentDistance);
           }
-        `,
+  
+          color = mix(0.0, color, step(
+            distanceNdcPixelSize + SURFACE_OFFSET,
+            -myMinDistance
+          ));
+          minDistance = -myMinDistance;
+        }
+      `,
       distanceFunctionName: 'invertedTunnelMinDistance',
     },
-    uniformName: 'invertedTunnels',
+    propertyUniformMapping: {
+      from: 'froms',
+      toFromDelta: 'toFromDeltas',
+      fromRadius: 'fromRadii',
+      toRadius: 'toRadii',
+    },
     uniformCountMacroName: 'INVERTED_TUNNEL_COUNT',
     shaderCombinationSteps: [0, 1, 4, 16, 32],
     empty: new InvertedTunnel(vec2.fromValues(0, 0), vec2.fromValues(0, 0), 0, 0),

src/drawables/shapes/tunnel.ts

@@ -8,44 +8,46 @@ export class Tunnel extends Drawable {
   public static descriptor: DrawableDescriptor = {
     sdf: {
       shader: `
-          uniform struct Tunnel {
-            vec2 from;
-            vec2 toFromDelta;
-            float fromRadius;
-            float toRadius;
-          }[TUNNEL_COUNT] tunnels;
+        uniform vec2 froms[TUNNEL_COUNT];
+        uniform vec2 toFromDeltas[TUNNEL_COUNT];
+        uniform float fromRadii[TUNNEL_COUNT];
+        uniform float toRadii[TUNNEL_COUNT];
       
-          void tunnelMinDistance(inout float minDistance, inout float color) {
-            float myMinDistance = minDistance;
-            for (int i = 0; i < TUNNEL_COUNT; i++) {
-              Tunnel tunnel = tunnels[i];
-              vec2 targetFromDelta = position - tunnel.from;
+        void tunnelMinDistance(inout float minDistance, inout float color) {
+          float myMinDistance = minDistance;
+          for (int i = 0; i < TUNNEL_COUNT; i++) {
+            vec2 targetFromDelta = position - froms[i];
             
-              float h = clamp(
-                  dot(targetFromDelta, tunnel.toFromDelta)
-                / dot(tunnel.toFromDelta, tunnel.toFromDelta),
-                0.0, 1.0
-              );
+            float h = clamp(
+                dot(targetFromDelta, toFromDeltas[i])
+              / dot(toFromDeltas[i], toFromDeltas[i]),
+              0.0, 1.0
+            );
 
-              float currentDistance = -mix(
-                tunnel.fromRadius, tunnel.toRadius, h
-              ) + distance(
-                targetFromDelta, tunnel.toFromDelta * h
-              );
+            float currentDistance = -mix(
+              fromRadii[i], toRadii[i], h
+            ) + distance(
+              targetFromDelta, toFromDeltas[i] * h
+            );
     
-              myMinDistance = min(myMinDistance, currentDistance);
-            }
-      
-            color = mix(2.0, color, step(
-              distanceNdcPixelSize + SURFACE_OFFSET,
-              myMinDistance
-            ));
-            minDistance = min(minDistance, myMinDistance);
+            myMinDistance = min(myMinDistance, currentDistance);
           }
-        `,
+    
+          color = mix(2.0, color, step(
+            distanceNdcPixelSize + SURFACE_OFFSET,
+            myMinDistance
+          ));
+          minDistance = min(minDistance, myMinDistance);
+        }
+      `,
       distanceFunctionName: 'tunnelMinDistance',
     },
-    uniformName: 'tunnels',
+    propertyUniformMapping: {
+      from: 'froms',
+      toFromDelta: 'toFromDeltas',
+      fromRadius: 'fromRadii',
+      toRadius: 'toRadii',
+    },
     uniformCountMacroName: 'TUNNEL_COUNT',
     shaderCombinationSteps: [0, 1, 4, 16, 32],
     empty: new Tunnel(

src/graphics/graphics-library/frame-buffer/default-frame-buffer.ts

@@ -1,7 +1,8 @@
+import { UniversalRenderingContext } from '../universal-rendering-context';
 import { FrameBuffer } from './frame-buffer';
 
 export class DefaultFrameBuffer extends FrameBuffer {
-  constructor(gl: WebGL2RenderingContext) {
+  constructor(gl: UniversalRenderingContext) {
     super(gl);
     this.frameBuffer = null;
     this.setSize();

src/graphics/graphics-library/frame-buffer/frame-buffer.ts

@@ -1,4 +1,5 @@
 import { vec2 } from 'gl-matrix';
+import { UniversalRenderingContext } from '../universal-rendering-context';
 
 export abstract class FrameBuffer {
   public renderScale = 1;
@@ -9,7 +10,7 @@ export abstract class FrameBuffer {
   // null means the default framebuffer
   protected frameBuffer: WebGLFramebuffer | null = null;
 
-  constructor(protected gl: WebGL2RenderingContext) {}
+  constructor(protected gl: UniversalRenderingContext) {}
 
   public bindAndClear(colorInput?: WebGLTexture) {
     this.gl.bindFramebuffer(this.gl.FRAMEBUFFER, this.frameBuffer);

src/graphics/graphics-library/frame-buffer/intermediate-frame-buffer.ts

@@ -1,14 +1,17 @@
 import { enableExtension } from '../helper/enable-extension';
+import { UniversalRenderingContext } from '../universal-rendering-context';
 import { FrameBuffer } from './frame-buffer';
 
 export class IntermediateFrameBuffer extends FrameBuffer {
   private frameTexture: WebGLTexture;
   private floatLinearEnabled = false;
 
-  constructor(gl: WebGL2RenderingContext) {
+  constructor(gl: UniversalRenderingContext) {
     super(gl);
 
-    enableExtension(gl, 'EXT_color_buffer_float');
+    if (gl.isWebGL2) {
+      enableExtension(gl, 'EXT_color_buffer_float');
+    }
 
     try {
       enableExtension(gl, 'OES_texture_float_linear');
@@ -45,12 +48,12 @@ export class IntermediateFrameBuffer extends FrameBuffer {
       this.gl.texImage2D(
         this.gl.TEXTURE_2D,
         0,
-        this.gl.RG16F,
+        this.gl.isWebGL2 ? this.gl.RG16F : this.gl.RGBA,
         this.size.x,
         this.size.y,
         0,
-        this.gl.RG,
-        this.gl.FLOAT,
+        this.gl.isWebGL2 ? this.gl.RG : this.gl.RGBA,
+        this.gl.isWebGL2 ? this.gl.FLOAT : this.gl.UNSIGNED_BYTE,
         null
       );
     }

src/graphics/graphics-library/helper/enable-extension.ts

@@ -1,4 +1,5 @@
 import { Insights } from '../../rendering/insights';
+import { UniversalRenderingContext } from '../universal-rendering-context';
 
 const extensions: Map<string, any> = new Map();
 
@@ -11,7 +12,7 @@ const logExtensions = () => {
 };
 
 export const tryEnableExtension = (
-  gl: WebGL2RenderingContext,
+  gl: UniversalRenderingContext,
   name: string
 ): any | null => {
   if (extensions.has(name)) {
@@ -30,7 +31,7 @@ export const tryEnableExtension = (
   return extension;
 };
 
-export const enableExtension = (gl: WebGL2RenderingContext, name: string): any => {
+export const enableExtension = (gl: UniversalRenderingContext, name: string): any => {
   const extension = tryEnableExtension(gl, name);
 
   if (extension === null) {

src/graphics/graphics-library/helper/get-webgl2-context.ts

@@ -1,9 +0,0 @@
-export const getWebGl2Context = (canvas: HTMLCanvasElement): WebGL2RenderingContext => {
-  const gl = canvas.getContext('webgl2');
-
-  if (!gl) {
-    throw new Error('WebGl2 is not supported');
-  }
-
-  return gl;
-};

src/graphics/graphics-library/helper/load-uniform.ts

@@ -1,20 +1,21 @@
 import { mat3, ReadonlyVec3, vec2, vec3 } from 'gl-matrix';
+import { UniversalRenderingContext } from '../universal-rendering-context';
 
 const loaderMat3 = mat3.create();
 
 export const loadUniform = (
-  gl: WebGL2RenderingContext,
+  gl: UniversalRenderingContext,
   value: any,
   type: GLenum,
   location: WebGLUniformLocation
 ): any => {
   const converters: Map<
     GLenum,
-    (gl: WebGL2RenderingContext, value: any, location: WebGLUniformLocation) => void
+    (gl: UniversalRenderingContext, value: any, location: WebGLUniformLocation) => void
   > = new Map();
   {
-    converters.set(WebGL2RenderingContext.FLOAT, (gl, v, l) => {
-      if (v instanceof Array) {
+    converters.set(WebGLRenderingContext.FLOAT, (gl, v, l) => {
+      if (v instanceof Array || v[0] instanceof Float32Array) {
         if (v.length == 0) {
           return;
         }
@@ -25,19 +26,18 @@ export const loadUniform = (
       }
     });
 
-    converters.set(WebGL2RenderingContext.FLOAT_VEC2, (gl, v: vec2 | Array<vec2>, l) => {
+    converters.set(WebGLRenderingContext.FLOAT_VEC2, (gl, v: vec2 | Array<vec2>, l) => {
       if (v.length == 0) {
         return;
       }
 
-      if (v[0] instanceof Array) {
+      if (v[0] instanceof Array || v[0] instanceof Float32Array) {
         const result = new Float32Array(v.length * 2);
 
         for (let i = 0; i < v.length; i++) {
           result[2 * i] = (v[i] as Array<number>).x;
           result[2 * i + 1] = (v[i] as Array<number>).y;
         }
-
         gl.uniform2fv(l, result);
       } else {
         gl.uniform2fv(l, v as vec2);
@@ -45,13 +45,13 @@ export const loadUniform = (
     });
 
     converters.set(
-      WebGL2RenderingContext.FLOAT_VEC3,
+      WebGLRenderingContext.FLOAT_VEC3,
       (gl, v: ReadonlyVec3 | Array<vec3>, l) => {
         if (v.length == 0) {
           return;
         }
 
-        if (v[0] instanceof Array) {
+        if (v[0] instanceof Array || v[0] instanceof Float32Array) {
           const result = new Float32Array(v.length * 3);
 
           for (let i = 0; i < v.length; i++) {
@@ -67,11 +67,19 @@ export const loadUniform = (
       }
     );
 
-    converters.set(WebGL2RenderingContext.FLOAT_MAT3, (gl, v, l) => {
-      gl.uniformMatrix3fv(l, true, mat3.fromMat2d(loaderMat3, v));
+    converters.set(WebGLRenderingContext.FLOAT_MAT3, (gl, v, l) => {
+      if (gl.isWebGL2) {
+        gl.uniformMatrix3fv(l, true, mat3.fromMat2d(loaderMat3, v));
+      } else {
+        gl.uniformMatrix3fv(
+          l,
+          false,
+          mat3.transpose(mat3.create(), mat3.fromMat2d(loaderMat3, v))
+        );
+      }
     });
 
-    converters.set(WebGL2RenderingContext.BOOL, (gl, v, l) => gl.uniform1i(l, v));
+    converters.set(WebGLRenderingContext.BOOL, (gl, v, l) => gl.uniform1i(l, v));
 
     if (!converters.has(type)) {
       throw new Error(`Unimplemented webgl type: ${type}`);

src/graphics/graphics-library/helper/stopwatch.ts

@@ -1,3 +1,4 @@
+import { UniversalRenderingContext } from '../universal-rendering-context';
 import { enableExtension } from './enable-extension';
 
 enum StopwatchState {
@@ -13,7 +14,7 @@ export class WebGlStopwatch {
   private timerExtension: any;
   private timerQuery?: WebGLQuery;
 
-  constructor(private gl: WebGL2RenderingContext) {
+  constructor(private gl: UniversalRenderingContext) {
     this.timerExtension = enableExtension(gl, 'EXT_disjoint_timer_query_webgl2');
   }
 

src/graphics/graphics-library/parallel-compiler.ts

@@ -1,18 +1,23 @@
 import { wait } from '../../helper/wait';
 import { Insights } from '../rendering/insights';
 import { tryEnableExtension } from './helper/enable-extension';
+import { UniversalRenderingContext } from './universal-rendering-context';
 
 type CompilingProgram = {
   program: WebGLProgram;
   resolvePromise: ((program: WebGLProgram) => void) | null;
+  vertexShader: ShaderWithSource;
+  fragmentShader: ShaderWithSource;
 };
 
+type ShaderWithSource = WebGLShader & { source: string };
+
 export abstract class ParallelCompiler {
   private static extension?: any;
-  private static gl: WebGL2RenderingContext;
+  private static gl: UniversalRenderingContext;
   private static programs: Array<CompilingProgram> = [];
 
-  public static initialize(gl: WebGL2RenderingContext) {
+  public static initialize(gl: UniversalRenderingContext) {
     ParallelCompiler.gl = gl;
     ParallelCompiler.extension = tryEnableExtension(gl, 'KHR_parallel_shader_compile');
   }
@@ -28,14 +33,14 @@ export abstract class ParallelCompiler {
     // can only return null on lost context
     const program = ParallelCompiler.gl.createProgram()!;
 
-    ParallelCompiler.compileShader(
+    const vertexShader = ParallelCompiler.compileShader(
       vertexShaderSource,
       ParallelCompiler.gl.VERTEX_SHADER,
       program,
       substitutions
     );
 
-    ParallelCompiler.compileShader(
+    const fragmentShader = ParallelCompiler.compileShader(
       fragmentShaderSource,
       ParallelCompiler.gl.FRAGMENT_SHADER,
       program,
@@ -45,6 +50,8 @@ export abstract class ParallelCompiler {
     ParallelCompiler.programs.push({
       program,
       resolvePromise,
+      vertexShader,
+      fragmentShader,
     });
 
     return promise;
@@ -67,7 +74,7 @@ export abstract class ParallelCompiler {
     type: GLenum,
     program: WebGLProgram,
     substitutions: { [name: string]: string }
-  ) {
+  ): ShaderWithSource {
     const processedSource = source.replace(/{(.+)}/gm, (_, name: string): string => {
       const value = substitutions[name];
       return Number.isInteger(value) ? `${value}.0` : value;
@@ -79,7 +86,11 @@ export abstract class ParallelCompiler {
     this.gl.shaderSource(shader, processedSource);
     this.gl.compileShader(shader);
     this.gl.attachShader(program, shader);
-    this.gl.deleteShader(shader);
+
+    const result = shader as ShaderWithSource;
+    result.source = processedSource;
+
+    return result;
   }
 
   private static resolveFinishedPrograms() {
@@ -93,7 +104,7 @@ export abstract class ParallelCompiler {
           ParallelCompiler.extension.COMPLETION_STATUS_KHR
         )
       ) {
-        ParallelCompiler.checkProgram(p.program);
+        ParallelCompiler.checkProgram(p);
         done.push(p);
         p.resolvePromise!(p.program);
       }
@@ -104,18 +115,39 @@ export abstract class ParallelCompiler {
     );
   }
 
-  private static checkProgram(program: WebGLProgram) {
+  private static checkProgram(program: CompilingProgram) {
     const success = ParallelCompiler.gl.getProgramParameter(
-      program,
+      program.program,
       ParallelCompiler.gl.LINK_STATUS
     );
 
     if (!success && !ParallelCompiler.gl.isContextLost()) {
-      ParallelCompiler.gl.getAttachedShaders(program)?.forEach((s) => {
-        ParallelCompiler.checkShader(s);
-      });
+      ParallelCompiler.prettyPrintErrorsIfThereAreAny(program.vertexShader);
+      ParallelCompiler.prettyPrintErrorsIfThereAreAny(program.fragmentShader);
 
-      throw new Error(ParallelCompiler.gl.getProgramInfoLog(program)!);
+      throw new Error(ParallelCompiler.gl.getProgramInfoLog(program.program)!);
+    }
+
+    this.gl.deleteShader(program.vertexShader);
+    this.gl.deleteShader(program.fragmentShader);
+  }
+
+  private static prettyPrintErrorsIfThereAreAny(shader: ShaderWithSource) {
+    try {
+      ParallelCompiler.checkShader(shader);
+    } catch (e) {
+      for (const match of e
+        .toString()
+        .matchAll(/ERROR: 0:(?<line>\d+): (?<error>.*)$/gm)) {
+        const line = Number.parseInt(match.groups.line);
+        const error = match.groups.error;
+        console.error(
+          `Error: ${error}\nSource (line ${line}):\n${
+            shader.source.split('\n')[line - 1]
+          }`
+        );
+      }
+      throw new Error('Error while compiling shader');
     }
   }
 

src/graphics/graphics-library/program/fragment-shader-only-program.ts

@@ -1,10 +1,13 @@
+import { enableExtension } from '../helper/enable-extension';
+import { UniversalRenderingContext } from '../universal-rendering-context';
 import Program from './program';
 
 export class FragmentShaderOnlyProgram extends Program {
   private vao?: WebGLVertexArrayObject;
-
-  constructor(gl: WebGL2RenderingContext) {
+  private vertexArrayExtension: any;
+  constructor(gl: UniversalRenderingContext) {
     super(gl);
+    this.vertexArrayExtension = enableExtension(this.gl, 'OES_vertex_array_object');
   }
 
   public async initialize(
@@ -17,7 +20,11 @@ export class FragmentShaderOnlyProgram extends Program {
 
   public bind() {
     super.bind();
-    this.gl.bindVertexArray(this.vao!);
+    if (this.gl.isWebGL2) {
+      this.gl.bindVertexArray(this.vao!);
+    } else {
+      this.vertexArrayExtension.createVertexArrayOES();
+    }
   }
 
   public draw(uniforms: { [name: string]: any }) {
@@ -26,7 +33,12 @@ export class FragmentShaderOnlyProgram extends Program {
   }
 
   public destroy(): void {
-    this.gl.deleteVertexArray(this.vao!);
+    if (this.gl.isWebGL2) {
+      this.gl.deleteVertexArray(this.vao!);
+    } else {
+      this.vertexArrayExtension.deleteVertexArrayOES(this.vao!);
+    }
+
     super.destroy();
   }
 
@@ -45,10 +57,15 @@ export class FragmentShaderOnlyProgram extends Program {
       this.gl.STATIC_DRAW
     );
 
-    // can only return null on lost context
-    this.vao = this.gl.createVertexArray()!;
+    if (this.gl.isWebGL2) {
+      // can only return null on lost context
+      this.vao = this.gl.createVertexArray()!;
+      this.gl.bindVertexArray(this.vao!);
+    } else {
+      this.vao = this.vertexArrayExtension.createVertexArrayOES();
+      this.vertexArrayExtension.bindVertexArrayOES(this.vao!);
+    }
 
-    this.gl.bindVertexArray(this.vao);
     this.gl.enableVertexAttribArray(positionAttributeLocation);
     this.gl.vertexAttribPointer(positionAttributeLocation, 2, this.gl.FLOAT, false, 0, 0);
   }

src/graphics/graphics-library/program/program.ts

@@ -1,6 +1,7 @@
 import { mat2d, vec2 } from 'gl-matrix';
 import { loadUniform } from '../helper/load-uniform';
 import { ParallelCompiler } from '../parallel-compiler';
+import { UniversalRenderingContext } from '../universal-rendering-context';
 import { IProgram } from './i-program';
 
 export default abstract class Program implements IProgram {
@@ -14,7 +15,7 @@ export default abstract class Program implements IProgram {
     type: GLenum;
   }> = [];
 
-  constructor(protected gl: WebGL2RenderingContext) {}
+  constructor(protected gl: UniversalRenderingContext) {}
 
   public async initialize(
     [vertexShaderSource, fragmentShaderSource]: [string, string],
@@ -67,7 +68,7 @@ export default abstract class Program implements IProgram {
   private queryUniforms() {
     const uniformCount = this.gl.getProgramParameter(
       this.program!,
-      WebGL2RenderingContext.ACTIVE_UNIFORMS
+      WebGLRenderingContext.ACTIVE_UNIFORMS
     );
 
     for (let i = 0; i < uniformCount; i++) {

src/graphics/graphics-library/program/uniform-array-autoscaling-program.ts

@@ -2,6 +2,7 @@ import { mat2d, vec2 } from 'gl-matrix';
 import { DrawableDescriptor } from '../../../drawables/drawable-descriptor';
 import { getCombinations } from '../../../helper/get-combinations';
 import { last } from '../../../helper/last';
+import { UniversalRenderingContext } from '../universal-rendering-context';
 import { FragmentShaderOnlyProgram } from './fragment-shader-only-program';
 import { IProgram } from './i-program';
 
@@ -16,7 +17,7 @@ export class UniformArrayAutoScalingProgram implements IProgram {
   private drawingRectangleBottomLeft = vec2.fromValues(0, 0);
   private drawingRectangleSize = vec2.fromValues(1, 1);
 
-  constructor(private gl: WebGL2RenderingContext) {}
+  constructor(private gl: UniversalRenderingContext) {}
 
   public async initialize(
     shaderSources: [string, string],
@@ -44,9 +45,14 @@ export class UniformArrayAutoScalingProgram implements IProgram {
   }
 
   public draw(uniforms: { [name: string]: any }): void {
-    const values = this.descriptors!.map((d) =>
-      uniforms[d.uniformName] ? uniforms[d.uniformName].length : 0
-    );
+    const values = this.descriptors!.map((d) => {
+      const uniformNames = last(Object.entries(d.propertyUniformMapping));
+      if (!uniformNames) {
+        return 0;
+      }
+      const uniformName = uniformNames[1];
+      return uniforms[uniformName] ? uniforms[uniformName].length : 0;
+    });
 
     const closest = this.programs.find((p) => p.values.every((v, i) => v >= values[i]));
 

src/graphics/graphics-library/universal-rendering-context.ts

@@ -0,0 +1,34 @@
+import { Insights } from '../rendering/insights';
+
+export type UniversalRenderingContext = WebGL2RenderingContext &
+  WebGLRenderingContext & { isWebGL2: boolean };
+
+export const getUniversalRenderingContext = (
+  canvas: HTMLCanvasElement,
+  ignoreWebGL2 = false
+): UniversalRenderingContext => {
+  let context: WebGL2RenderingContext | WebGLRenderingContext | null = ignoreWebGL2
+    ? null
+    : canvas.getContext('webgl2');
+
+  let webgl2Support = true;
+
+  if (!context) {
+    context = canvas.getContext('webgl');
+    webgl2Support = false;
+  }
+
+  if (!context) {
+    context = canvas.getContext('experimental-webgl') as WebGLRenderingContext;
+  }
+
+  if (!context) {
+    throw new Error('Neither WebGL or WebGL2 is supported');
+  }
+
+  Insights.setValue('using WebGL2', webgl2Support);
+
+  const result = context as UniversalRenderingContext;
+  result.isWebGL2 = webgl2Support;
+  return result;
+};

src/graphics/rendering/render-pass/render-pass.ts

@@ -1,11 +1,12 @@
 import { DrawableDescriptor } from '../../../drawables/drawable-descriptor';
 import { FrameBuffer } from '../../graphics-library/frame-buffer/frame-buffer';
 import { UniformArrayAutoScalingProgram } from '../../graphics-library/program/uniform-array-autoscaling-program';
+import { UniversalRenderingContext } from '../../graphics-library/universal-rendering-context';
 
 export abstract class RenderPass {
   protected program: UniformArrayAutoScalingProgram;
 
-  constructor(gl: WebGL2RenderingContext, protected frame: FrameBuffer) {
+  constructor(gl: UniversalRenderingContext, protected frame: FrameBuffer) {
     this.program = new UniformArrayAutoScalingProgram(gl);
   }