Merge pull request #674 from LLK/revert-673-revert-660-revert-489

Revert "Revert "Revert "Merge pull request #489 from adroitwhiz/touching-white-fixes"""

Author: fsih

src/RenderWebGL.js

@@ -188,23 +188,9 @@ class RenderWebGL extends EventEmitter {
         /** @type {function} */
         this._exitRegion = null;
 
-        /** @type {object} */
-        this._backgroundDrawRegionId = {
-            enter: () => this._enterDrawBackground(),
-            exit: () => this._exitDrawBackground()
-        };
-
         /** @type {Array.<snapshotCallback>} */
         this._snapshotCallbacks = [];
 
-        /** @type {Array<number>} */
-        // Don't set this directly-- use setBackgroundColor so it stays in sync with _backgroundColor3b
-        this._backgroundColor4f = [0, 0, 0, 1];
-
-        /** @type {Uint8ClampedArray} */
-        // Don't set this directly-- use setBackgroundColor so it stays in sync with _backgroundColor4f
-        this._backgroundColor3b = new Uint8ClampedArray(3);
-
         this._createGeometry();
 
         this.on(RenderConstants.Events.NativeSizeChanged, this.onNativeSizeChanged);
@@ -264,14 +250,7 @@ class RenderWebGL extends EventEmitter {
      * @param {number} blue The blue component for the background.
      */
     setBackgroundColor (red, green, blue) {
-        this._backgroundColor4f[0] = red;
-        this._backgroundColor4f[1] = green;
-        this._backgroundColor4f[2] = blue;
-
-        this._backgroundColor3b[0] = red * 255;
-        this._backgroundColor3b[1] = green * 255;
-        this._backgroundColor3b[2] = blue * 255;
-
+        this._backgroundColor = [red, green, blue, 1];
     }
 
     /**
@@ -650,7 +629,7 @@ class RenderWebGL extends EventEmitter {
 
         twgl.bindFramebufferInfo(gl, null);
         gl.viewport(0, 0, gl.canvas.width, gl.canvas.height);
-        gl.clearColor.apply(gl, this._backgroundColor4f);
+        gl.clearColor.apply(gl, this._backgroundColor);
         gl.clear(gl.COLOR_BUFFER_BIT);
 
         this._drawThese(this._drawList, ShaderManager.DRAW_MODE.default, this._projection);
@@ -766,20 +745,12 @@ class RenderWebGL extends EventEmitter {
      */
     isTouchingColor (drawableID, color3b, mask3b) {
         const candidates = this._candidatesTouching(drawableID, this._visibleDrawList);
-
-        let bounds;
-        if (colorMatches(color3b, this._backgroundColor3b, 0)) {
-            // If the color we're checking for is the background color, don't confine the check to
-            // candidate drawables' bounds--since the background spans the entire stage, we must check
-            // everything that lies inside the drawable.
-            bounds = this._touchingBounds(drawableID);
-        } else if (candidates.length === 0) {
-            // If not checking for the background color, we can return early if there are no candidate drawables.
+        if (candidates.length === 0) {
             return false;
-        } else {
-            bounds = this._candidatesBounds(candidates);
         }
 
+        const bounds = this._candidatesBounds(candidates);
+
         const maxPixelsForCPU = this._getMaxPixelsForCPU();
 
         const debugCanvasContext = this._debugCanvas && this._debugCanvas.getContext('2d');
@@ -840,19 +811,6 @@ class RenderWebGL extends EventEmitter {
         }
     }
 
-    _enterDrawBackground () {
-        const gl = this.gl;
-        const currentShader = this._shaderManager.getShader(ShaderManager.DRAW_MODE.background, 0);
-        gl.disable(gl.BLEND);
-        gl.useProgram(currentShader.program);
-        twgl.setBuffersAndAttributes(gl, currentShader, this._bufferInfo);
-    }
-
-    _exitDrawBackground () {
-        const gl = this.gl;
-        gl.enable(gl.BLEND);
-    }
-
     _isTouchingColorGpuStart (drawableID, candidateIDs, bounds, color3b, mask3b) {
         this._doExitDrawRegion();
 
@@ -864,8 +822,15 @@ class RenderWebGL extends EventEmitter {
         gl.viewport(0, 0, bounds.width, bounds.height);
         const projection = twgl.m4.ortho(bounds.left, bounds.right, bounds.top, bounds.bottom, -1, 1);
 
-        // Clear the query buffer to fully transparent. This will be the color of pixels that fail the stencil test.
-        gl.clearColor(0, 0, 0, 0);
+        let fillBackgroundColor = this._backgroundColor;
+
+        // When using masking such that the background fill color will showing through, ensure we don't
+        // fill using the same color that we are trying to detect!
+        if (color3b[0] > 196 && color3b[1] > 196 && color3b[2] > 196) {
+            fillBackgroundColor = [0, 0, 0, 255];
+        }
+
+        gl.clearColor.apply(gl, fillBackgroundColor);
         gl.clear(gl.COLOR_BUFFER_BIT | gl.STENCIL_BUFFER_BIT);
 
         let extraUniforms;
@@ -877,9 +842,6 @@ class RenderWebGL extends EventEmitter {
         }
 
         try {
-            // Using the stencil buffer, mask out the drawing to either the drawable's alpha channel
-            // or pixels of the drawable which match the mask color, depending on whether a mask color is given.
-            // Masked-out pixels will not be checked.
             gl.enable(gl.STENCIL_TEST);
             gl.stencilFunc(gl.ALWAYS, 1, 1);
             gl.stencilOp(gl.KEEP, gl.KEEP, gl.REPLACE);
@@ -900,25 +862,12 @@ class RenderWebGL extends EventEmitter {
             gl.stencilOp(gl.KEEP, gl.KEEP, gl.KEEP);
             gl.colorMask(true, true, true, true);
 
-            // Draw the background as a quad. Drawing a background with gl.clear will not mask to the stenciled area.
-            this.enterDrawRegion(this._backgroundDrawRegionId);
-
-            const uniforms = {
-                u_backgroundColor: this._backgroundColor4f
-            };
-
-            const currentShader = this._shaderManager.getShader(ShaderManager.DRAW_MODE.background, 0);
-            twgl.setUniforms(currentShader, uniforms);
-            twgl.drawBufferInfo(gl, this._bufferInfo, gl.TRIANGLES);
-
-            // Draw the candidate drawables on top of the background.
             this._drawThese(candidateIDs, ShaderManager.DRAW_MODE.default, projection,
                 {idFilterFunc: testID => testID !== drawableID}
             );
         } finally {
             gl.colorMask(true, true, true, true);
             gl.disable(gl.STENCIL_TEST);
-            this._doExitDrawRegion();
         }
     }
 
@@ -937,8 +886,7 @@ class RenderWebGL extends EventEmitter {
         }
 
         for (let pixelBase = 0; pixelBase < pixels.length; pixelBase += 4) {
-            // Transparent pixels are masked (either by the drawable's alpha channel or color mask).
-            if (pixels[pixelBase + 3] !== 0 && colorMatches(color3b, pixels, pixelBase)) {
+            if (colorMatches(color3b, pixels, pixelBase)) {
                 return true;
             }
         }
@@ -1373,7 +1321,7 @@ class RenderWebGL extends EventEmitter {
         gl.viewport(0, 0, bounds.width, bounds.height);
         const projection = twgl.m4.ortho(bounds.left, bounds.right, bounds.top, bounds.bottom, -1, 1);
 
-        gl.clearColor.apply(gl, this._backgroundColor4f);
+        gl.clearColor.apply(gl, this._backgroundColor);
         gl.clear(gl.COLOR_BUFFER_BIT);
         this._drawThese(this._drawList, ShaderManager.DRAW_MODE.default, projection);
 
@@ -1461,13 +1409,6 @@ class RenderWebGL extends EventEmitter {
                     // Update the CPU position data
                     drawable.updateCPURenderAttributes();
                     const candidateBounds = drawable.getFastBounds();
-
-                    // Push bounds out to integers. If a drawable extends out into half a pixel, that half-pixel still
-                    // needs to be tested. Plus, in some areas we construct another rectangle from the union of these,
-                    // and iterate over its pixels (width * height). Turns out that doesn't work so well when the
-                    // width/height aren't integers.
-                    candidateBounds.snapToInt();
-
                     if (bounds.intersects(candidateBounds)) {
                         result.push({
                             id,

src/ShaderManager.js

@@ -176,12 +176,7 @@ ShaderManager.DRAW_MODE = {
     /**
      * Draw a line with caps.
      */
-    line: 'line',
-
-    /**
-     * Draw the background in a certain color. Must sometimes be used instead of gl.clear.
-     */
-    background: 'background'
+    line: 'line'
 };
 
 module.exports = ShaderManager;

src/shaders/sprite.frag

@@ -39,15 +39,9 @@ uniform float u_lineThickness;
 uniform float u_lineLength;
 #endif // DRAW_MODE_line
 
-#ifdef DRAW_MODE_background
-uniform vec4 u_backgroundColor;
-#endif // DRAW_MODE_background
-
 uniform sampler2D u_skin;
 
-#ifndef DRAW_MODE_background
 varying vec2 v_texCoord;
-#endif
 
 // Add this to divisors to prevent division by 0, which results in NaNs propagating through calculations.
 // Smaller values can cause problems on some mobile devices.
@@ -115,7 +109,7 @@ const vec2 kCenter = vec2(0.5, 0.5);
 
 void main()
 {
-	#if !(defined(DRAW_MODE_line) || defined(DRAW_MODE_background))
+	#ifndef DRAW_MODE_line
 	vec2 texcoord0 = v_texCoord;
 
 	#ifdef ENABLE_mosaic
@@ -221,9 +215,7 @@ void main()
 	gl_FragColor.rgb /= gl_FragColor.a + epsilon;
 	#endif
 
-	#endif // !(defined(DRAW_MODE_line) || defined(DRAW_MODE_background))
-
-	#ifdef DRAW_MODE_line
+	#else // DRAW_MODE_line
 	// Maaaaagic antialiased-line-with-round-caps shader.
 
 	// "along-the-lineness". This increases parallel to the line.
@@ -242,8 +234,4 @@ void main()
 	// the closer we are to the line, invert it.
 	gl_FragColor = u_lineColor * clamp(1.0 - line, 0.0, 1.0);
 	#endif // DRAW_MODE_line
-
-	#ifdef DRAW_MODE_background
-	gl_FragColor = u_backgroundColor;
-	#endif
 }

src/shaders/sprite.vert

@@ -14,7 +14,7 @@ uniform vec4 u_penPoints;
 const float epsilon = 1e-3;
 #endif
 
-#if !(defined(DRAW_MODE_line) || defined(DRAW_MODE_background))
+#ifndef DRAW_MODE_line
 uniform mat4 u_projectionMatrix;
 uniform mat4 u_modelMatrix;
 attribute vec2 a_texCoord;
@@ -66,8 +66,6 @@ void main() {
 	// 4. Apply view transform
 	position *= 2.0 / u_stageSize;
 	gl_Position = vec4(position, 0, 1);
-	#elif defined(DRAW_MODE_background)
-	gl_Position = vec4(a_position * 2.0, 0, 1);
 	#else
 	gl_Position = u_projectionMatrix * u_modelMatrix * vec4(a_position, 0, 1);
 	v_texCoord = a_texCoord;