Fixed the filter masking on iOS. Forgot OpenGL ES 2.0 didn't support …

…GL_ALPHA_TEST.

examples/Mac/FilterShowcase/FilterShowcase/FilterOperations.swift

@@ -388,7 +388,12 @@ let filterOperations: Array<FilterOperationInterface> = [
         filterOperationType:.Custom(filterSetupFunction:{(camera, filter, outputView) in
             let castFilter = filter as! Pixellate
             castFilter.fractionalWidthOfAPixel = 0.05
+            // TODO: Find a way to not hardcode these values
+#if os(iOS)
+            let circleGenerator = CircleGenerator(size:Size(width:480, height:640))
+#else
             let circleGenerator = CircleGenerator(size:Size(width:1280, height:720))
+#endif
             castFilter.mask = circleGenerator
             circleGenerator.renderCircleOfRadius(0.25, center:Position.Center, circleColor:Color.White, backgroundColor:Color.Transparent)
             camera --> castFilter --> outputView

framework/Source/Framebuffer.swift

@@ -36,6 +36,7 @@ public enum FramebufferTimingStyle {
 public class Framebuffer {
     let texture:GLuint
     let framebuffer:GLuint?
+    let stencilBuffer:GLuint?
     let size:GLSize
     let orientation:ImageOrientation
     let internalFormat:Int32
@@ -65,12 +66,16 @@ public class Framebuffer {
 
         if (!textureOnly) {
             do {
-                framebuffer = try generateFramebufferForTexture(texture, width:size.width, height:size.height, internalFormat:internalFormat, format:format, type:type, stencil:stencil)
+                let (createdFrameBuffer, createdStencil) = try generateFramebufferForTexture(texture, width:size.width, height:size.height, internalFormat:internalFormat, format:format, type:type, stencil:stencil)
+                framebuffer = createdFrameBuffer
+                stencilBuffer = createdStencil
             } catch {
+                stencilBuffer = nil
                 framebuffer = nil
                 throw error
             }
         } else {
+            stencilBuffer = nil
             framebuffer = nil
         }
     }
@@ -86,6 +91,11 @@ public class Framebuffer {
 			var mutableFramebuffer = framebuffer
             glDeleteFramebuffers(1, &mutableFramebuffer)
         }
+
+        if let stencilBuffer = stencilBuffer {
+            var mutableStencil = stencilBuffer
+            glDeleteRenderbuffers(1, &mutableStencil)
+        }
     }
 
     func sizeForTargetOrientation(targetOrientation:ImageOrientation) -> GLSize {

framework/Source/OpenGLRendering.swift

@@ -84,24 +84,30 @@ func clearFramebufferWithColor(color:Color) {
 
 func renderStencilMaskFromFramebuffer(framebuffer:Framebuffer) {
     let inputTextureProperties = framebuffer.texturePropertiesForOutputRotation(.NoRotation)
+    glEnable(GLenum(GL_STENCIL_TEST))
     glClearStencil(0)
     glClear (GLenum(GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT))
     glColorMask(GLboolean(GL_FALSE), GLboolean(GL_FALSE), GLboolean(GL_FALSE), GLboolean(GL_FALSE))
-    glDisable(GLenum(GL_DEPTH_TEST))
-    glEnable(GLenum(GL_STENCIL_TEST))
-    glEnable(GLenum(GL_ALPHA_TEST))
-    glBlendFunc(GLenum(GL_ONE), GLenum(GL_ONE))
-    glAlphaFunc(GLenum(GL_NOTEQUAL), 0.0)
     glStencilFunc(GLenum(GL_ALWAYS), 1, 1)
     glStencilOp(GLenum(GL_KEEP), GLenum(GL_KEEP), GLenum(GL_REPLACE))
 
+#if GL
+    glEnable(GLenum(GL_ALPHA_TEST))
+    glAlphaFunc(GLenum(GL_NOTEQUAL), 0.0)
     renderQuadWithShader(sharedImageProcessingContext.passthroughShader, vertices:standardImageVertices, inputTextures:[inputTextureProperties])
+#else
+    let alphaTestShader = crashOnShaderCompileFailure("Stencil"){return try sharedImageProcessingContext.programForVertexShader(OneInputVertexShader, fragmentShader:AlphaTestFragmentShader)}
+    renderQuadWithShader(alphaTestShader, vertices:standardImageVertices, inputTextures:[inputTextureProperties])
+#endif
 
     glColorMask(GLboolean(GL_TRUE), GLboolean(GL_TRUE), GLboolean(GL_TRUE), GLboolean(GL_TRUE))
+
     glStencilFunc(GLenum(GL_EQUAL), 1, 1)
     glStencilOp(GLenum(GL_KEEP), GLenum(GL_KEEP), GLenum(GL_KEEP))
 
+#if GL
     glDisable(GLenum(GL_ALPHA_TEST))
+#endif
 }
 
 func disableStencil() {
@@ -139,7 +145,7 @@ func generateTexture(minFilter minFilter:Int32, magFilter:Int32, wrapS:Int32, wr
     return texture
 }
 
-func generateFramebufferForTexture(texture:GLuint, width:GLint, height:GLint, internalFormat:Int32, format:Int32, type:Int32, stencil:Bool) throws -> GLuint {
+func generateFramebufferForTexture(texture:GLuint, width:GLint, height:GLint, internalFormat:Int32, format:Int32, type:Int32, stencil:Bool) throws -> (GLuint, GLuint?) {
     var framebuffer:GLuint = 0
     glActiveTexture(GLenum(GL_TEXTURE1))
 
@@ -155,22 +161,30 @@ func generateFramebufferForTexture(texture:GLuint, width:GLint, height:GLint, in
         throw FramebufferCreationError(errorCode:status)
     }
 
+    let stencilBuffer:GLuint?
     if stencil {
-        try attachStencilBuffer(width:width, height:height)
+        stencilBuffer = try attachStencilBuffer(width:width, height:height)
+    } else {
+        stencilBuffer = nil
     }
 
     glBindTexture(GLenum(GL_TEXTURE_2D), 0)
     glBindFramebuffer(GLenum(GL_FRAMEBUFFER), 0)
-    return framebuffer
+    return (framebuffer, stencilBuffer)
 }
 
 func attachStencilBuffer(width width:GLint, height:GLint) throws -> GLuint {
     var stencilBuffer:GLuint = 0
     glGenRenderbuffers(1, &stencilBuffer);
     glBindRenderbuffer(GLenum(GL_RENDERBUFFER), stencilBuffer)
     glRenderbufferStorage(GLenum(GL_RENDERBUFFER), GLenum(GL_DEPTH24_STENCIL8), width, height) // iOS seems to only support combination depth + stencil, from references
+#if os(iOS)
+    glFramebufferRenderbuffer(GLenum(GL_FRAMEBUFFER), GLenum(GL_DEPTH_ATTACHMENT), GLenum(GL_RENDERBUFFER), stencilBuffer)
+#endif
     glFramebufferRenderbuffer(GLenum(GL_FRAMEBUFFER), GLenum(GL_STENCIL_ATTACHMENT), GLenum(GL_RENDERBUFFER), stencilBuffer)
 
+    glBindRenderbuffer(GLenum(GL_RENDERBUFFER), 0)
+
     let status = glCheckFramebufferStatus(GLenum(GL_FRAMEBUFFER))
     if (status != GLenum(GL_FRAMEBUFFER_COMPLETE)) {
         throw FramebufferCreationError(errorCode:status)

framework/Source/Operations/Shaders/AlphaTest_GL.fsh

@@ -0,0 +1,16 @@
+varying vec2 textureCoordinate;
+
+uniform sampler2D inputImageTexture;
+
+void main()
+{
+    vec4 color = texture2D(inputImageTexture, textureCoordinate);
+    if (color.a < 0.5) 
+    {
+        discard;
+    } 
+    else
+    {
+        gl_FragColor = color;
+    }
+}

framework/Source/Operations/Shaders/AlphaTest_GLES.fsh

@@ -0,0 +1,16 @@
+varying highp vec2 textureCoordinate;
+
+uniform sampler2D inputImageTexture;
+
+void main()
+{
+    lowp vec4 color = texture2D(inputImageTexture, textureCoordinate);
+    if (color.a < 0.5) 
+    {
+        discard;
+    } 
+    else
+    {
+        gl_FragColor = color;
+    }
+}

framework/Source/Operations/Shaders/ConvertedShaders_GL.swift

@@ -1,6 +1,7 @@
 public let AdaptiveThresholdFragmentShader = "varying vec2 textureCoordinate;\n varying vec2 textureCoordinate2;\n \n uniform sampler2D inputImageTexture;\n uniform sampler2D inputImageTexture2;\n \n void main()\n {\n     float blurredInput = texture2D(inputImageTexture, textureCoordinate).r;\n     float localLuminance = texture2D(inputImageTexture2, textureCoordinate2).r;\n     float thresholdResult = step(blurredInput - 0.05, localLuminance);\n     \n     gl_FragColor = vec4(vec3(thresholdResult), 1.0);\n }\n "
 public let AddBlendFragmentShader = "varying vec2 textureCoordinate;\n varying vec2 textureCoordinate2;\n \n uniform sampler2D inputImageTexture;\n uniform sampler2D inputImageTexture2;\n \n void main()\n {\n     vec4 base = texture2D(inputImageTexture, textureCoordinate);\n     vec4 overlay = texture2D(inputImageTexture2, textureCoordinate2);\n  \n     float r;\n     if (overlay.r * base.a + base.r * overlay.a >= overlay.a * base.a) {\n         r = overlay.a * base.a + overlay.r * (1.0 - base.a) + base.r * (1.0 - overlay.a);\n     } else {\n         r = overlay.r + base.r;\n     }\n     \n     float g;\n     if (overlay.g * base.a + base.g * overlay.a >= overlay.a * base.a) {\n         g = overlay.a * base.a + overlay.g * (1.0 - base.a) + base.g * (1.0 - overlay.a);\n     } else {\n         g = overlay.g + base.g;\n     }\n     \n     float b;\n     if (overlay.b * base.a + base.b * overlay.a >= overlay.a * base.a) {\n         b = overlay.a * base.a + overlay.b * (1.0 - base.a) + base.b * (1.0 - overlay.a);\n     } else {\n         b = overlay.b + base.b;\n     }\n     \n     float a = overlay.a + base.a - overlay.a * base.a;\n     \n     gl_FragColor = vec4(r, g, b, a);\n }\n "
 public let AlphaBlendFragmentShader = "varying vec2 textureCoordinate;\n varying vec2 textureCoordinate2;\n \n uniform sampler2D inputImageTexture;\n uniform sampler2D inputImageTexture2;\n \n uniform float mixturePercent;\n \n void main()\n {\n  vec4 textureColor = texture2D(inputImageTexture, textureCoordinate);\n  vec4 textureColor2 = texture2D(inputImageTexture2, textureCoordinate2);\n  \n  gl_FragColor = vec4(mix(textureColor.rgb, textureColor2.rgb, textureColor2.a * mixturePercent), textureColor.a);\n }\n "
+public let AlphaTestFragmentShader = "varying vec2 textureCoordinate;\n \n uniform sampler2D inputImageTexture;\n \n void main()\n {\n     vec4 color = texture2D(inputImageTexture, textureCoordinate);\n     if (color.a < 0.5) \n     {\n         discard;\n     } \n     else\n     {\n         gl_FragColor = color;\n     }\n }\n "
 public let AverageColorVertexShader = "attribute vec4 position;\n attribute vec4 inputTextureCoordinate;\n \n uniform float texelWidth;\n uniform float texelHeight;\n \n varying vec2 upperLeftInputTextureCoordinate;\n varying vec2 upperRightInputTextureCoordinate;\n varying vec2 lowerLeftInputTextureCoordinate;\n varying vec2 lowerRightInputTextureCoordinate;\n \n void main()\n {\n     gl_Position = position;\n     \n     upperLeftInputTextureCoordinate = inputTextureCoordinate.xy + vec2(-texelWidth, -texelHeight);\n     upperRightInputTextureCoordinate = inputTextureCoordinate.xy + vec2(texelWidth, -texelHeight);\n     lowerLeftInputTextureCoordinate = inputTextureCoordinate.xy + vec2(-texelWidth, texelHeight);\n     lowerRightInputTextureCoordinate = inputTextureCoordinate.xy + vec2(texelWidth, texelHeight);\n }\n "
 public let AverageColorFragmentShader = "uniform sampler2D inputImageTexture;\n \n varying vec2 outputTextureCoordinate;\n \n varying vec2 upperLeftInputTextureCoordinate;\n varying vec2 upperRightInputTextureCoordinate;\n varying vec2 lowerLeftInputTextureCoordinate;\n varying vec2 lowerRightInputTextureCoordinate;\n \n void main()\n {\n     vec4 upperLeftColor = texture2D(inputImageTexture, upperLeftInputTextureCoordinate);\n     vec4 upperRightColor = texture2D(inputImageTexture, upperRightInputTextureCoordinate);\n     vec4 lowerLeftColor = texture2D(inputImageTexture, lowerLeftInputTextureCoordinate);\n     vec4 lowerRightColor = texture2D(inputImageTexture, lowerRightInputTextureCoordinate);\n     \n     gl_FragColor = 0.25 * (upperLeftColor + upperRightColor + lowerLeftColor + lowerRightColor);\n }\n "
 public let AverageLuminanceFragmentShader = "uniform sampler2D inputImageTexture;\n \n varying vec2 outputTextureCoordinate;\n \n varying vec2 upperLeftInputTextureCoordinate;\n varying vec2 upperRightInputTextureCoordinate;\n varying vec2 lowerLeftInputTextureCoordinate;\n varying vec2 lowerRightInputTextureCoordinate;\n \n void main()\n {\n     float upperLeftLuminance = texture2D(inputImageTexture, upperLeftInputTextureCoordinate).r;\n     float upperRightLuminance = texture2D(inputImageTexture, upperRightInputTextureCoordinate).r;\n     float lowerLeftLuminance = texture2D(inputImageTexture, lowerLeftInputTextureCoordinate).r;\n     float lowerRightLuminance = texture2D(inputImageTexture, lowerRightInputTextureCoordinate).r;\n     \n     float luminosity = 0.25 * (upperLeftLuminance + upperRightLuminance + lowerLeftLuminance + lowerRightLuminance);\n     gl_FragColor = vec4(luminosity, luminosity, luminosity, 1.0);\n }\n "

framework/Source/Operations/Shaders/ConvertedShaders_GLES.swift

@@ -1,6 +1,7 @@
 public let AdaptiveThresholdFragmentShader = "varying highp vec2 textureCoordinate;\n varying highp vec2 textureCoordinate2;\n \n uniform sampler2D inputImageTexture;\n uniform sampler2D inputImageTexture2; \n \n void main()\n {\n     highp float blurredInput = texture2D(inputImageTexture, textureCoordinate).r;\n     highp float localLuminance = texture2D(inputImageTexture2, textureCoordinate2).r;\n     highp float thresholdResult = step(blurredInput - 0.05, localLuminance);\n     \n     gl_FragColor = vec4(vec3(thresholdResult), 1.0);\n }\n "
 public let AddBlendFragmentShader = "varying highp vec2 textureCoordinate;\n varying highp vec2 textureCoordinate2;\n \n uniform sampler2D inputImageTexture;\n uniform sampler2D inputImageTexture2;\n \n void main()\n {\n   lowp vec4 base = texture2D(inputImageTexture, textureCoordinate);\n   lowp vec4 overlay = texture2D(inputImageTexture2, textureCoordinate2);\n  \n   mediump float r;\n   if (overlay.r * base.a + base.r * overlay.a >= overlay.a * base.a) {\n     r = overlay.a * base.a + overlay.r * (1.0 - base.a) + base.r * (1.0 - overlay.a);\n   } else {\n     r = overlay.r + base.r;\n   }\n \n   mediump float g;\n   if (overlay.g * base.a + base.g * overlay.a >= overlay.a * base.a) {\n     g = overlay.a * base.a + overlay.g * (1.0 - base.a) + base.g * (1.0 - overlay.a);\n   } else {\n     g = overlay.g + base.g;\n   }\n \n   mediump float b;\n   if (overlay.b * base.a + base.b * overlay.a >= overlay.a * base.a) {\n     b = overlay.a * base.a + overlay.b * (1.0 - base.a) + base.b * (1.0 - overlay.a);\n   } else {\n     b = overlay.b + base.b;\n   }\n \n   mediump float a = overlay.a + base.a - overlay.a * base.a;\n   \n   gl_FragColor = vec4(r, g, b, a);\n }\n "
 public let AlphaBlendFragmentShader = "varying highp vec2 textureCoordinate;\n varying highp vec2 textureCoordinate2;\n \n uniform sampler2D inputImageTexture;\n uniform sampler2D inputImageTexture2;\n \n uniform lowp float mixturePercent;\n \n void main()\n {\n  lowp vec4 textureColor = texture2D(inputImageTexture, textureCoordinate);\n  lowp vec4 textureColor2 = texture2D(inputImageTexture2, textureCoordinate2);\n  \n  gl_FragColor = vec4(mix(textureColor.rgb, textureColor2.rgb, textureColor2.a * mixturePercent), textureColor.a);\n }\n "
+public let AlphaTestFragmentShader = "varying highp vec2 textureCoordinate;\n \n uniform sampler2D inputImageTexture;\n \n void main()\n {\n     lowp vec4 color = texture2D(inputImageTexture, textureCoordinate);\n     if (color.a < 0.5) \n     {\n         discard;\n     } \n     else\n     {\n         gl_FragColor = color;\n     }\n }\n "
 public let AverageColorVertexShader = "attribute vec4 position;\n attribute vec4 inputTextureCoordinate;\n \n uniform float texelWidth;\n uniform float texelHeight;\n \n varying vec2 upperLeftInputTextureCoordinate;\n varying vec2 upperRightInputTextureCoordinate;\n varying vec2 lowerLeftInputTextureCoordinate;\n varying vec2 lowerRightInputTextureCoordinate;\n \n void main()\n {\n     gl_Position = position;\n     \n     upperLeftInputTextureCoordinate = inputTextureCoordinate.xy + vec2(-texelWidth, -texelHeight);\n     upperRightInputTextureCoordinate = inputTextureCoordinate.xy + vec2(texelWidth, -texelHeight);\n     lowerLeftInputTextureCoordinate = inputTextureCoordinate.xy + vec2(-texelWidth, texelHeight);\n     lowerRightInputTextureCoordinate = inputTextureCoordinate.xy + vec2(texelWidth, texelHeight);\n }\n "
 public let AverageColorFragmentShader = "precision highp float;\n \n uniform sampler2D inputImageTexture;\n \n varying highp vec2 outputTextureCoordinate;\n \n varying highp vec2 upperLeftInputTextureCoordinate;\n varying highp vec2 upperRightInputTextureCoordinate;\n varying highp vec2 lowerLeftInputTextureCoordinate;\n varying highp vec2 lowerRightInputTextureCoordinate;\n \n void main()\n {\n     highp vec4 upperLeftColor = texture2D(inputImageTexture, upperLeftInputTextureCoordinate);\n     highp vec4 upperRightColor = texture2D(inputImageTexture, upperRightInputTextureCoordinate);\n     highp vec4 lowerLeftColor = texture2D(inputImageTexture, lowerLeftInputTextureCoordinate);\n     highp vec4 lowerRightColor = texture2D(inputImageTexture, lowerRightInputTextureCoordinate);\n     \n     gl_FragColor = 0.25 * (upperLeftColor + upperRightColor + lowerLeftColor + lowerRightColor);\n }\n "
 public let AverageLuminanceFragmentShader = "precision highp float;\n \n uniform sampler2D inputImageTexture;\n \n varying highp vec2 outputTextureCoordinate;\n \n varying highp vec2 upperLeftInputTextureCoordinate;\n varying highp vec2 upperRightInputTextureCoordinate;\n varying highp vec2 lowerLeftInputTextureCoordinate;\n varying highp vec2 lowerRightInputTextureCoordinate;\n \n void main()\n {\n     highp float upperLeftLuminance = texture2D(inputImageTexture, upperLeftInputTextureCoordinate).r;\n     highp float upperRightLuminance = texture2D(inputImageTexture, upperRightInputTextureCoordinate).r;\n     highp float lowerLeftLuminance = texture2D(inputImageTexture, lowerLeftInputTextureCoordinate).r;\n     highp float lowerRightLuminance = texture2D(inputImageTexture, lowerRightInputTextureCoordinate).r;\n     \n     highp float luminosity = 0.25 * (upperLeftLuminance + upperRightLuminance + lowerLeftLuminance + lowerRightLuminance);\n     gl_FragColor = vec4(luminosity, luminosity, luminosity, 1.0);\n }\n "