shader.cpp

/*
 * Copyright 2013 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.
 */
#include "platform.h"

#include <EGL/egl.h>
#include <GLES2/gl2.h>

#include "shader.h"
#include <stdlib.h>
#include <stdio.h>

#define DEBUG (1)

bool shader::CompileShader(GLuint *shader, const GLenum type,
                           const GLchar *source, const int32_t iSize) {
  if (source == NULL || iSize <= 0) return false;

  *shader = glCreateShader(type);
  glShaderSource(*shader, 1, &source, &iSize);  // Not specifying 3rd parameter
                                                // (size) could be troublesome..

  glCompileShader(*shader);

#if defined(DEBUG)
  GLint logLength;
  glGetShaderiv(*shader, GL_INFO_LOG_LENGTH, &logLength);
  if (logLength > 0) {
    GLchar *log = (GLchar *)malloc(logLength);
    glGetShaderInfoLog(*shader, logLength, &logLength, log);
    PRINT("Shader compile log:\n%s", log);
    free(log);
  }
#endif

  GLint status;
  glGetShaderiv(*shader, GL_COMPILE_STATUS, &status);
  if (status == 0) {
    PRINT("compile failure\n");
    glDeleteShader(*shader);
    return false;
  }

  return true;
}

bool shader::CompileShader(GLuint *shader, const GLenum type,
                           std::vector<uint8_t> &data) {
  if (!data.size()) return false;

  const GLchar *source = (GLchar *)&data[0];
  int32_t iSize = data.size();
  return shader::CompileShader(shader, type, source, iSize);
}

bool shader::LinkProgram(const GLuint prog) {
  GLint status;

  glLinkProgram(prog);

 #if defined(DEBUG)
   GLint logLength;
   glGetProgramiv(prog, GL_INFO_LOG_LENGTH, &logLength);
   if (logLength > 0) {
     GLchar *log = (GLchar *)malloc(logLength);
     glGetProgramInfoLog(prog, logLength, &logLength, log);
     PRINT("Program link log:\n%s", log);
     free(log);
   }
 #endif

  glGetProgramiv(prog, GL_LINK_STATUS, &status);
  if (status == 0) {
    PRINT("Program link failed\n");
    return false;
  }

  return true;
}

bool shader::ValidateProgram(const GLuint prog) {
  GLint logLength, status;

  glValidateProgram(prog);
  glGetProgramiv(prog, GL_INFO_LOG_LENGTH, &logLength);
   if (logLength > 0) {
     GLchar *log = (GLchar *)malloc(logLength);
     glGetProgramInfoLog(prog, logLength, &logLength, log);
     PRINT("Program validate log:\n%s", log);
     free(log);
   }

  glGetProgramiv(prog, GL_VALIDATE_STATUS, &status);
  if (status == 0) return false;

  return true;
}