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//
// IFImageFilter.m
// InstaFilters
//
// Created by Di Wu on 2/28/12.
// Copyright (c) 2012 twitter: @diwup. All rights reserved.
//
  
#import "IFImageFilter.h"
  
@interface IFImageFilter ()
{
GLint filterPositionAttribute, filterTextureCoordinateAttribute;
GLint filterInputTextureUniform, filterInputTextureUniform2, filterInputTextureUniform3, filterInputTextureUniform4, filterInputTextureUniform5, filterInputTextureUniform6;
  
GLuint filterFramebuffer;
}
  
@end
  
@implementation IFImageFilter
  
-(id) initWithFragmentShaderFromString: (NSString *) fragmentShaderString;
{
if (! (self = [super init]))
{
return nil;
}
  
[GPUImageOpenGLESContext useImageProcessingContext];
filterProgram = [[GLProgram alloc] initWithVertexShaderString: kGPUImageVertexShaderString fragmentShaderString: fragmentShaderString];
  
[filterProgram addAttribute: @ "position"];
[filterProgram addAttribute: @ "inputTextureCoordinate"];
  
if (! [filterProgram link])
{
NSString * progLog = [filterProgram programLog];
NSLog (@ "Program link log:% @", progLog);
NSString * fragLog = [filterProgram fragmentShaderLog];
NSLog (@ "Fragment shader compile log:% @", fragLog);
NSString * vertLog = [filterProgram vertexShaderLog];
NSLog (@ "Vertex shader compile log:% @", vertLog);
filterProgram = nil;
NSAssert (NO, @ "Filter shader link failed");
}
  
filterPositionAttribute = [filterProgram attributeIndex: @ "position"];
filterTextureCoordinateAttribute = [filterProgram attributeIndex: @ "inputTextureCoordinate"];
filterInputTextureUniform = [filterProgram uniformIndex: @ "inputImageTexture"]; // This does assume a name of "inputImageTexture" for the fragment shader
filterInputTextureUniform2 = [filterProgram uniformIndex: @ "inputImageTexture2"]; // This does assume a name of "inputImageTexture2" for second input texture in the fragment shader
filterInputTextureUniform3 = [filterProgram uniformIndex: @ "inputImageTexture3"]; // This does assume a name of "inputImageTexture3" for second input texture in the fragment shader
filterInputTextureUniform4 = [filterProgram uniformIndex: @ "inputImageTexture4"]; // This does assume a name of "inputImageTexture4" for second input texture in the fragment shader
filterInputTextureUniform5 = [filterProgram uniformIndex: @ "inputImageTexture5"]; // This does assume a name of "inputImageTexture5" for second input texture in the fragment shader
filterInputTextureUniform6 = [filterProgram uniformIndex: @ "inputImageTexture6"]; // This does assume a name of "inputImageTexture6" for second input texture in the fragment shader
  
[filterProgram use];
glEnableVertexAttribArray (filterPositionAttribute);
glEnableVertexAttribArray (filterTextureCoordinateAttribute);
NSLog (@ ". 0.0.0% @", NSStringFromCGSize (inputTextureSize));
  
return self;
}
  
-(void) renderToTextureWithVertices: (const GLfloat *) vertices textureCoordinates: (const GLfloat *) textureCoordinates;
{
NSLog (@ ". 0.0.0% @", NSStringFromCGSize (inputTextureSize));
  
[GPUImageOpenGLESContext useImageProcessingContext];
[self setFilterFBO];
  
[filterProgram use];
  
glClearColor (0.0f, 0.0f, 0.0f, 1.0f);
glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
  
glActiveTexture (GL_TEXTURE2);
glBindTexture (GL_TEXTURE_2D, filterSourceTexture);
  
glUniform1i (filterInputTextureUniform, 2);
  
if (filterSourceTexture2! = 0)
{
glActiveTexture (GL_TEXTURE3);
glBindTexture (GL_TEXTURE_2D, filterSourceTexture2);
  
glUniform1i (filterInputTextureUniform2, 3);
}
if (filterSourceTexture3! = 0)
{
glActiveTexture (GL_TEXTURE4);
glBindTexture (GL_TEXTURE_2D, filterSourceTexture3);
glUniform1i (filterInputTextureUniform3, 4);
}
if (filterSourceTexture4! = 0)
{
glActiveTexture (GL_TEXTURE5);
glBindTexture (GL_TEXTURE_2D, filterSourceTexture4);
glUniform1i (filterInputTextureUniform4, 5);
}
if (filterSourceTexture5! = 0)
{
glActiveTexture (GL_TEXTURE6);
glBindTexture (GL_TEXTURE_2D, filterSourceTexture5);
glUniform1i (filterInputTextureUniform5, 6);
}
if (filterSourceTexture6! = 0)
{
glActiveTexture (GL_TEXTURE7);
glBindTexture (GL_TEXTURE_2D, filterSourceTexture6);
glUniform1i (filterInputTextureUniform6, 7);
}
  
glVertexAttribPointer (filterPositionAttribute, 2, GL_FLOAT, 0, 0, vertices);
glVertexAttribPointer (filterTextureCoordinateAttribute, 2, GL_FLOAT, 0, 0, textureCoordinates);
  
glDrawArrays (GL_TRIANGLE_STRIP, 0, 4);
  
for (id <GPUImageInput> currentTarget in targets)
{
[currentTarget setInputSize: inputTextureSize];
[currentTarget newFrameReady];
}
}
  
-(void) setFilterFBO;
{
if (! filterFramebuffer)
{
[self createFilterFBO];
}
  
glBindFramebuffer (GL_FRAMEBUFFER, filterFramebuffer);
  
CGSize currentFBOSize = [self sizeOfFBO];
glViewport (0, 0, (int) currentFBOSize.width, (int) currentFBOSize.height);
}
  
-(void) createFilterFBO;
{
glActiveTe
xture (GL_TEXTURE1);
glGenFramebuffers (1, & filterFramebuffer);
glBindFramebuffer (GL_FRAMEBUFFER, filterFramebuffer);
NSLog (@ ". 0.0.0% @", NSStringFromCGSize (inputTextureSize));
CGSize currentFBOSize = [self sizeOfFBO];
// NSLog (@ "Filter size:% f,% f", currentFBOSize.width, currentFBOSize.height);
  
glRenderbufferStorage (GL_RENDERBUFFER, GL_RGBA8_OES, (int) currentFBOSize.width, (int) currentFBOSize.height);
glBindTexture (GL_TEXTURE_2D, outputTexture);
glTexImage2D (GL_TEXTURE_2D, 0, GL_RGBA, (int) currentFBOSize.width, (int) currentFBOSize.height, 0, GL_RGBA, GL_UNSIGNED_BYTE, 0);
glFramebufferTexture2D (GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, outputTexture, 0);
  
GLenum status = glCheckFramebufferStatus (GL_FRAMEBUFFER);
  
NSAssert (status == GL_FRAMEBUFFER_COMPLETE, @ "Incomplete filter FBO:% d", status);
}
  
-(CGSize) sizeOfFBO;
{
CGSize outputSize = [self maximumOutputSize];
if ((CGSizeEqualToSize (outputSize, CGSizeZero)) || (inputTextureSize.width <outputSize.width))
{
return inputTextureSize;
}
else
{
return outputSize;
}
}
  
-(void) setInputTexture: (GLuint) newInputTexture atIndex: (NSInteger) textureIndex;
{
if (textureIndex == 0)
{
filterSourceTexture = newInputTexture;
}
else if (filterSourceTexture2 == 0)
{
filterSourceTexture2 = newInputTexture;
}
else if (filterSourceTexture3 == 0) {
filterSourceTexture3 = newInputTexture;
}
else if (filterSourceTexture4 == 0) {
filterSourceTexture4 = newInputTexture;
}
else if (filterSourceTexture5 == 0) {
filterSourceTexture5 = newInputTexture;
}
else if (filterSourceTexture6 == 0) {
filterSourceTexture6 = newInputTexture;
}
  
}
  
@end


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