Android GPUImage implementation of GPUImageTwoPassFilter

GPUImageTwoPassFilter.java

package jp.co.cyberagent.android.gpuimage;

import static jp.co.cyberagent.android.gpuimage.GPUImageRenderer.CUBE;
import static jp.co.cyberagent.android.gpuimage.utils.TextureRotationUtils.TEXTURE_NO_ROTATION;

import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.FloatBuffer;
import java.nio.IntBuffer;

import jp.co.cyberagent.android.gpuimage.utils.TextureRotationUtils;
import android.opengl.GLES20;
import android.util.Log;

public class GPUImageTwoPassFilter1 extends GPUImageFilter {
  final static String TAG = "GPUImageTwoPassFilter";
	//int secondFilterOutputTexture;
	
	int secondFilterPositionAttribute;
	int secondFilterTextureCoordinateAttribute;
	
	int secondFilterInputTextureUniform;
	int secondFilterInputTextureUniform2;
	int secondFilterProgram;
	
	private ByteBuffer mTexture2CoordinatesBuffer;
	String secondStageVertexShader;
	String secondStageFragmentShader;
    
    
    private int[] secondFilterFramebuffer;
    private int[] secondFilterOutputTexture;
    private int outputTexture;
	public GPUImageTwoPassFilter1(String firstStageVertexShaderString, String firstStageFragmentShaderString, String secondStageVertexShaderString, String secondStageFragmentShaderString){
		super(firstStageVertexShaderString, firstStageFragmentShaderString);
		Log.d(TAG, "Full Constructor");
		secondStageVertexShader = secondStageVertexShaderString;
		secondStageFragmentShader = secondStageFragmentShaderString;
	}
	
	public GPUImageTwoPassFilter1(String firstStageFragmentShaderString, String secondStageFragmentShaderString){
		this(NO_FILTER_VERTEX_SHADER, firstStageFragmentShaderString, NO_FILTER_VERTEX_SHADER, secondStageFragmentShaderString);
		Log.d(TAG, "Second Constructor");
		secondStageVertexShader = NO_FILTER_VERTEX_SHADER;
		secondStageFragmentShader = secondStageFragmentShaderString;
	}
	
	@Override
    public void onInit() {
        super.onInit();

        //create the second filter program
        Log.d("Second Filter Program", "Pre Load");
        secondFilterProgram = OpenGlUtils.loadProgram(secondStageVertexShader, secondStageFragmentShader);
        Log.d("Second Filter Program", secondFilterProgram + "");
        secondFilterPositionAttribute = GLES20.glGetAttribLocation(secondFilterProgram, "position");
        secondFilterTextureCoordinateAttribute = GLES20.glGetAttribLocation(secondFilterProgram, "inputTextureCoordinate");
        
        secondFilterInputTextureUniform =  GLES20.glGetUniformLocation(secondFilterProgram, "inputImageTexture");
        secondFilterInputTextureUniform2 = GLES20.glGetUniformLocation(secondFilterProgram, "inputImageTexture2");
        
        //TODO: [GPUImageOpenGLESContext setActiveShaderProgram:secondFilterProgram]; ??
        GLES20.glUseProgram(secondFilterProgram);
        GLES20.glEnableVertexAttribArray(secondFilterPositionAttribute);
        GLES20.glEnableVertexAttribArray(secondFilterTextureCoordinateAttribute);

    }
	
	
	
	
    @Override
	public void onDraw(final int textureId, final FloatBuffer cubeBuffer,final FloatBuffer textureBuffer){
		//do the first pass, as usual
		super.onDraw(textureId, cubeBuffer, textureBuffer);
		
		//createSecondFilterFBO
		if(secondFilterFramebuffer == null){
			//createFilterFBOOfSize
			secondFilterFramebuffer = new int[1];
	    	Log.d(TAG, "creating filter framebuffer");
	    	
	    	
			  GLES20.glGenFramebuffers(1, secondFilterFramebuffer, 0);
	    	GLES20.glBindFramebuffer(GLES20.GL_FRAMEBUFFER, secondFilterFramebuffer[0]);
	    	
	    	if(secondFilterOutputTexture == null){
	    		Log.d(TAG, "creating second output texture");
	    		secondFilterOutputTexture = new int[1];
	    		GLES20.glGenTextures(1, secondFilterOutputTexture, 0);
		    	GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, secondFilterOutputTexture[0]);
		    	GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MIN_FILTER, GLES20.GL_LINEAR);
		    	GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MAG_FILTER, GLES20.GL_LINEAR);
		        GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_S, GLES20.GL_CLAMP_TO_EDGE);
		        GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_T, GLES20.GL_CLAMP_TO_EDGE);
		        GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, 0);
	    	}
	    	
	        GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, secondFilterOutputTexture[0]);
	        GLES20.glTexImage2D(GLES20.GL_TEXTURE_2D, 0, GLES20.GL_RGBA, width, height, 0,GLES20.GL_RGBA, GLES20.GL_UNSIGNED_BYTE, null);
	        GLES20.glFramebufferTexture2D(GLES20.GL_FRAMEBUFFER, GLES20.GL_COLOR_ATTACHMENT0, GLES20.GL_TEXTURE_2D, secondFilterOutputTexture[0], 0);
		    	GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, 0);
		}
		int status = GLES20.glCheckFramebufferStatus(GLES20.GL_FRAMEBUFFER);
		if(status != GLES20.GL_FRAMEBUFFER_COMPLETE){
			Log.d(TAG, "framebuffer failed to create");
		}
		    GLES20.glBindFramebuffer(GLES20.GL_FRAMEBUFFER, secondFilterFramebuffer[0]);
	    	//GLES20.glViewport(0, 0, width, height);
		
		     //change the program
      	GLES20.glUseProgram(secondFilterProgram);
      	
      	//clear the old colors
        GLES20.glClearColor(0, 0, 0, 1);
        GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT);
		
        
		
      	GLES20.glActiveTexture(GLES20.GL_TEXTURE3); //ios version is GL_TEXTURE3
		    //TODO: change this texture to be the correct input texture
      	GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, secondFilterOutputTexture[0]);
        GLES20.glUniform1i(secondFilterInputTextureUniform, 3);
        
        
        cubeBuffer.position(0);
        
        GLES20.glVertexAttribPointer(secondFilterPositionAttribute, 2, GLES20.GL_FLOAT, false, 0, cubeBuffer);
        GLES20.glEnableVertexAttribArray(secondFilterPositionAttribute);
        
        textureBuffer.position(0);
        //TODO: change the textureBuffer to be NO ROTATION
        GLES20.glVertexAttribPointer(secondFilterTextureCoordinateAttribute, 2, GLES20.GL_FLOAT, false, 0, textureBuffer);
        GLES20.glEnableVertexAttribArray(secondFilterTextureCoordinateAttribute); 
        
        
        
        
        GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4);
        GLES20.glDisableVertexAttribArray(secondFilterPositionAttribute);
        GLES20.glDisableVertexAttribArray(secondFilterTextureCoordinateAttribute);
        GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, 0);
        
        GLES20.glBindFramebuffer(GLES20.GL_FRAMEBUFFER, 0);
        
	}
}

For anyone looking at this code, I'm pretty sure the issue is that I have 2 different textures (the first one is the textureId passed into onDraw, the second is generated separately, represented as secondFilterOutputTexture). I'm not sure how to take the first texture in for a second pass.

On how to use the previous texture, look at GPUImageFilterGroup. There in onDraw you see the previousTexture which is used as input for the onDraw method of the filters.

did you get this work?