Android Open Source - android_shaderize Obj Shader

• Back to OpenGL/Shade  ↑

From Project

Back to project page android_shaderize.

License

The source code is released under:

Apache License

Java Source Code

package fi.harism.shaderize;
// www  .jav a2 s . c  om
import java.util.HashMap;

import android.opengl.GLES20;
import android.util.Log;

/**
 * Helper class for handling shaders.
 */
public final class ObjShader {

  // Shader program handles.
  private int mProgram = 0;
  private int mShaderFragment = 0;
  // HashMap for storing uniform/attribute handles.
  private final HashMap<String, Integer> mShaderHandleMap = new HashMap<String, Integer>();
  private int mShaderVertex = 0;

  /**
   * Deletes program and shaders associated with it.
   */
  public void deleteProgram() {
    GLES20.glDeleteShader(mShaderFragment);
    GLES20.glDeleteShader(mShaderVertex);
    GLES20.glDeleteProgram(mProgram);
    mProgram = mShaderVertex = mShaderFragment = 0;
  }

  /**
   * Get id for given handle name. This method checks for both attribute and
   * uniform handles.
   * 
   * @param name
   *            Name of handle.
   * @return Id for given handle or -1 if none found.
   */
  public int getHandle(String name) {
    if (mShaderHandleMap.containsKey(name)) {
      return mShaderHandleMap.get(name);
    }
    int handle = GLES20.glGetAttribLocation(mProgram, name);
    if (handle == -1) {
      handle = GLES20.glGetUniformLocation(mProgram, name);
    }
    if (handle == -1) {
      // One should never leave log messages but am not going to follow
      // this rule. This line comes handy if you see repeating 'not found'
      // messages on LogCat - usually for typos otherwise annoying to
      // spot from shader code.
      Log.d("GlslShader", "Could not get attrib location for " + name);
    } else {
      mShaderHandleMap.put(name, handle);
    }
    return handle;
  }

  /**
   * Get array of ids with given names. Returned array is sized to given
   * amount name elements.
   * 
   * @param names
   *            List of handle names.
   * @return array of handle ids.
   */
  public int[] getHandles(String... names) {
    int[] res = new int[names.length];
    for (int i = 0; i < names.length; ++i) {
      res[i] = getHandle(names[i]);
    }
    return res;
  }

  /**
   * Helper method for compiling a shader.
   * 
   * @param shaderType
   *            Type of shader to compile
   * @param source
   *            String presentation for shader
   * @return id for compiled shader
   */
  private int loadShader(int shaderType, String source) throws Exception {
    int shader = GLES20.glCreateShader(shaderType);
    if (shader != 0) {
      GLES20.glShaderSource(shader, source);
      GLES20.glCompileShader(shader);
      int[] compiled = new int[1];
      GLES20.glGetShaderiv(shader, GLES20.GL_COMPILE_STATUS, compiled, 0);
      if (compiled[0] == 0) {
        String error = GLES20.glGetShaderInfoLog(shader);
        GLES20.glDeleteShader(shader);
        throw new Exception(error);
      }
    }
    return shader;
  }

  /**
   * Compiles vertex and fragment shaders and links them into a program one
   * can use for rendering. Once OpenGL context is lost and onSurfaceCreated
   * is called, there is no need to reset existing GlslShader objects but one
   * can simply reload shader.
   * 
   * @param vertexSource
   *            String presentation for vertex shader
   * @param fragmentSource
   *            String presentation for fragment shader
   */
  public void setProgram(String vertexSource, String fragmentSource)
      throws Exception {
    mShaderVertex = loadShader(GLES20.GL_VERTEX_SHADER, vertexSource);
    mShaderFragment = loadShader(GLES20.GL_FRAGMENT_SHADER, fragmentSource);
    int program = GLES20.glCreateProgram();
    if (program != 0) {
      GLES20.glAttachShader(program, mShaderVertex);
      GLES20.glAttachShader(program, mShaderFragment);
      GLES20.glLinkProgram(program);
      int[] linkStatus = new int[1];
      GLES20.glGetProgramiv(program, GLES20.GL_LINK_STATUS, linkStatus, 0);
      if (linkStatus[0] != GLES20.GL_TRUE) {
        String error = GLES20.glGetProgramInfoLog(program);
        deleteProgram();
        throw new Exception(error);
      }
    }
    mProgram = program;
    mShaderHandleMap.clear();
  }

  /**
   * Activates this shader program.
   */
  public void useProgram() {
    GLES20.glUseProgram(mProgram);
  }

}

Java Source Code List

• Back to OpenGL/Shade  ↑