content: /*
   * Copyright (C) 2011 The Android Open Source Project
   *
   * 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 android.filterpacks.imageproc;
  
  import android.filterfw.core.Filter;
  import android.filterfw.core.FilterContext;
  import android.filterfw.core.Frame;
  import android.filterfw.core.FrameFormat;
  import android.filterfw.core.GenerateFieldPort;
  import android.filterfw.core.MutableFrameFormat;
  import android.filterfw.core.ShaderProgram;
  import android.filterfw.format.ImageFormat;
  import android.filterfw.geometry.Point;
  import android.filterfw.geometry.Quad;
  
  /**
   * The FixedRotationFilter rotates the input image clockwise, it only accepts
   * 4 rotation angles: 0, 90, 180, 270
   * @hide
   */
  public class FixedRotationFilter extends Filter {
  
      @GenerateFieldPort(name = "rotation", hasDefault = true)
      private int mRotation = 0;
  
      private ShaderProgram mProgram = null;
  
      public FixedRotationFilter(String name) {
          super(name);
      }
  
      @Override
      public void setupPorts() {
          addMaskedInputPort("image", ImageFormat.create(ImageFormat.COLORSPACE_RGBA,
                                                         FrameFormat.TARGET_GPU));
          addOutputBasedOnInput("image", "image");
      }
  
      @Override
      public FrameFormat getOutputFormat(String portName, FrameFormat inputFormat) {
          return inputFormat;
      }
  
      @Override
      public void process(FilterContext context) {
          Frame input = pullInput("image");
          if (mRotation == 0) {
              pushOutput("image", input);
              return;
          }
          FrameFormat inputFormat = input.getFormat();
  
          // Create program if not created already
          if (mProgram == null) {
              mProgram = ShaderProgram.createIdentity(context);
          }
          MutableFrameFormat outputFormat = inputFormat.mutableCopy();
          int width = inputFormat.getWidth();
          int height = inputFormat.getHeight();
          Point p1 = new Point(0.0f, 0.0f);
          Point p2 = new Point(1.0f, 0.0f);
          Point p3 = new Point(0.0f, 1.0f);
          Point p4 = new Point(1.0f, 1.0f);
          Quad sourceRegion;
          switch (((int)Math.round(mRotation / 90f)) % 4) {
              case 1:
                  sourceRegion = new Quad(p3,p1,p4,p2);
                  outputFormat.setDimensions(height, width);
                  break;
              case 2:
                  sourceRegion = new Quad(p4,p3,p2,p1);
                  break;
              case 3:
                  sourceRegion = new Quad(p2,p4,p1,p3);
                  outputFormat.setDimensions(height, width);
                  break;
              case 0:
              default:
                  sourceRegion = new Quad(p1,p2,p3,p4);
                  break;
          }
          // Create output frame
          Frame output = context.getFrameManager().newFrame(outputFormat);
  
          // Set the source region
          mProgram.setSourceRegion(sourceRegion);
  
          // Process
          mProgram.process(input, output);
  
          // Push output
          pushOutput("image", output);
  
          // Release pushed frame
          output.release();
      }
  }
  