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.Program;
  import android.filterfw.core.ShaderProgram;
  import android.filterfw.format.ImageFormat;
  import android.filterfw.geometry.Quad;
  import android.filterfw.geometry.Point;
  
  /**
   * @hide
   */
  public class RotateFilter extends Filter {
  
      @GenerateFieldPort(name = "angle")
      private int mAngle;
  
      @GenerateFieldPort(name = "tile_size", hasDefault = true)
      private int mTileSize = 640;
  
      private Program mProgram;
  
      private int mWidth = 0;
      private int mHeight = 0;
      private int mTarget = FrameFormat.TARGET_UNSPECIFIED;
  
      private int mOutputWidth;
      private int mOutputHeight;
  
      public RotateFilter(String name) {
          super(name);
      }
  
      @Override
      public void setupPorts() {
          addMaskedInputPort("image", ImageFormat.create(ImageFormat.COLORSPACE_RGBA));
          addOutputBasedOnInput("image", "image");
      }
  
      public void initProgram(FilterContext context, int target) {
          switch (target) {
              case FrameFormat.TARGET_GPU:
                  ShaderProgram shaderProgram = ShaderProgram.createIdentity(context);
                  shaderProgram.setMaximumTileSize(mTileSize);
                  shaderProgram.setClearsOutput(true);
                  mProgram = shaderProgram;
                  break;
  
              default:
                  throw new RuntimeException("Filter Sharpen does not support frames of " +
                      "target " + target + "!");
          }
          mTarget = target;
      }
  
      @Override
      public void fieldPortValueUpdated(String name, FilterContext context) {
          if (mProgram != null) {
              updateParameters();
          }
      }
  
      @Override
      public void process(FilterContext context) {
          // Get input frame
          Frame input = pullInput("image");
          FrameFormat inputFormat = input.getFormat();
  
          // Create program if not created already
          if (mProgram == null || inputFormat.getTarget() != mTarget) {
              initProgram(context, inputFormat.getTarget());
          }
  
          if (inputFormat.getWidth() != mWidth || inputFormat.getHeight() != mHeight) {
              mWidth = inputFormat.getWidth();
              mHeight = inputFormat.getHeight();
              mOutputWidth = mWidth;
              mOutputHeight = mHeight;
  
              updateParameters();
          }
  
          // Create output frame
          FrameFormat outputFormat = ImageFormat.create(mOutputWidth, mOutputHeight,
                                                        ImageFormat.COLORSPACE_RGBA,
                                                        FrameFormat.TARGET_GPU);
  
          Frame output = context.getFrameManager().newFrame(outputFormat);
  
          // Process
          mProgram.process(input, output);
  
          // Push output
          pushOutput("image", output);
  
          // Release pushed frame
          output.release();
      }
  
      private void updateParameters() {
          float sinTheta;
          float cosTheta;
  
          if (mAngle % 90 == 0) {
              if (mAngle % 180 == 0) {
                  sinTheta = 0f;
                  cosTheta = (mAngle % 360 == 0) ? 1f:-1f;
              } else {
                  cosTheta = 0f;
                  sinTheta = ((mAngle + 90) % 360 == 0) ? -1f:1f;
  
                  mOutputWidth = mHeight;
                  mOutputHeight = mWidth;
              }
          } else {
              throw new RuntimeException("degree has to be multiply of 90.");
          }
  
          Point x0 = new Point(0.5f * (-cosTheta + sinTheta + 1f),
                               0.5f * (-sinTheta - cosTheta + 1f));
          Point x1 = new Point(0.5f * (cosTheta + sinTheta + 1f),
                               0.5f * (sinTheta - cosTheta + 1f));
          Point x2 = new Point(0.5f * (-cosTheta - sinTheta + 1f),
                               0.5f * (-sinTheta + cosTheta + 1f));
          Point x3 = new Point(0.5f * (cosTheta - sinTheta + 1f),
                               0.5f * (sinTheta + cosTheta + 1f));
          Quad quad = new Quad(x0, x1, x2, x3);
          ((ShaderProgram) mProgram).setTargetRegion(quad);
      }
  }
  