content: /*
   * Copyright (C) 2012 CyberAgent
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   * http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package jp.co.cyberagent.android.gpuimage;
  
  import android.opengl.GLES20;
  
  /**
   * Applies a ColorMatrix to the image.
   */
  public class GPUImageColorMatrixFilter extends GPUImageFilter {
      public static final String COLOR_MATRIX_FRAGMENT_SHADER = "" +
              "varying highp vec2 textureCoordinate;\n" +
              "\n" +
              "uniform sampler2D inputImageTexture;\n" +
              "\n" +
              "uniform lowp mat4 colorMatrix;\n" +
              "uniform lowp float intensity;\n" +
              "\n" +
              "void main()\n" +
              "{\n" +
              "    lowp vec4 textureColor = texture2D(inputImageTexture, textureCoordinate);\n" +
              "    lowp vec4 outputColor = textureColor * colorMatrix;\n" +
              "    \n" +
              "    gl_FragColor = (intensity * outputColor) + ((1.0 - intensity) * textureColor);\n" +
              "}";
  
      private float mIntensity;
      private float[] mColorMatrix;
      private int mColorMatrixLocation;
      private int mIntensityLocation;
  
      public GPUImageColorMatrixFilter() {
          this(1.0f, new float[] {
                  1.0f, 0.0f, 0.0f, 0.0f,
                  0.0f, 1.0f, 0.0f, 0.0f,
                  0.0f, 0.0f, 1.0f, 0.0f,
                  0.0f, 0.0f, 0.0f, 1.0f
          });
      }
  
      public GPUImageColorMatrixFilter(final float intensity, final float[] colorMatrix) {
          super(NO_FILTER_VERTEX_SHADER, COLOR_MATRIX_FRAGMENT_SHADER);
          mIntensity = intensity;
          mColorMatrix = colorMatrix;
      }
  
      @Override
      public void onInit() {
          super.onInit();
          mColorMatrixLocation = GLES20.glGetUniformLocation(getProgram(), "colorMatrix");
          mIntensityLocation = GLES20.glGetUniformLocation(getProgram(), "intensity");
      }
  
      @Override
      public void onInitialized() {
          super.onInitialized();
          setIntensity(mIntensity);
          setColorMatrix(mColorMatrix);
      }
  
      public void setIntensity(final float intensity) {
          mIntensity = intensity;
          setFloat(mIntensityLocation, intensity);
      }
  
      public void setColorMatrix(final float[] colorMatrix) {
          mColorMatrix = colorMatrix;
          setUniformMatrix4f(mColorMatrixLocation, colorMatrix);
      }
  }
  