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.filterfw;
  
  import android.filterfw.core.CachedFrameManager;
  import android.filterfw.core.FilterContext;
  import android.filterfw.core.FrameManager;
  import android.filterfw.core.GLEnvironment;
  
  /**
   * Base class for mobile filter framework (MFF) frontend environments. These convenience classes
   * allow using the filter framework without the requirement of performing manual setup of its
   * required components.
   *
   * @hide
   */
  public class MffEnvironment {
  
      private FilterContext mContext;
  
      /**
       * Protected constructor to initialize the environment's essential components. These are the
       * frame-manager and the filter-context. Passing in null for the frame-manager causes this
       * to be auto-created.
       *
       * @param frameManager The FrameManager to use or null to auto-create one.
       */
      protected MffEnvironment(FrameManager frameManager) {
          // Get or create the frame manager
          if (frameManager == null) {
              frameManager = new CachedFrameManager();
          }
  
          // Setup the environment
          mContext = new FilterContext();
          mContext.setFrameManager(frameManager);
  
      }
  
      /**
       * Returns the environment's filter-context.
       */
      public FilterContext getContext() {
          return mContext;
      }
  
      /**
       * Set the environment's GL environment to the specified environment. This does not activate
       * the environment.
       */
      public void setGLEnvironment(GLEnvironment glEnvironment) {
          mContext.initGLEnvironment(glEnvironment);
      }
  
      /**
       * Create and activate a new GL environment for use in this filter context.
       */
      public void createGLEnvironment() {
          GLEnvironment glEnvironment = new GLEnvironment();
          glEnvironment.initWithNewContext();
          setGLEnvironment(glEnvironment);
      }
  
      /**
       * Activate the GL environment for use in the current thread. A GL environment must have been
       * previously set or created using setGLEnvironment() or createGLEnvironment()! Call this after
       * having switched to a new thread for GL filter execution.
       */
      public void activateGLEnvironment() {
          GLEnvironment glEnv = mContext.getGLEnvironment();
          if (glEnv != null) {
              mContext.getGLEnvironment().activate();
          } else {
              throw new NullPointerException("No GLEnvironment in place to activate!");
          }
      }
  
      /**
       * Deactivate the GL environment from use in the current thread. A GL environment must have been
       * previously set or created using setGLEnvironment() or createGLEnvironment()! Call this before
       * running GL filters in another thread.
       */
      public void deactivateGLEnvironment() {
          GLEnvironment glEnv = mContext.getGLEnvironment();
          if (glEnv != null) {
              mContext.getGLEnvironment().deactivate();
          } else {
              throw new NullPointerException("No GLEnvironment in place to deactivate!");
          }
      }
  }
  