Renamed gles_book_examples to gles2_book to make it shorter and more correct....

third_party/gles_book_examples/Chapter_9/MipMap2D/MipMap2D.c

Index: third_party/gles_book_examples/Chapter_9/MipMap2D/MipMap2D.c
===================================================================
--- third_party/gles_book_examples/Chapter_9/MipMap2D/MipMap2D.c	(revision 35873)
+++ third_party/gles_book_examples/Chapter_9/MipMap2D/MipMap2D.c	(working copy)
@@ -1,346 +0,0 @@
-//
-// Book:      OpenGL(R) ES 2.0 Programming Guide
-// Authors:   Aaftab Munshi, Dan Ginsburg, Dave Shreiner
-// ISBN-10:   0321502795
-// ISBN-13:   9780321502797
-// Publisher: Addison-Wesley Professional
-// URLs:      http://safari.informit.com/9780321563835
-//            http://www.opengles-book.com
-//
-
-// MipMap2D.c
-//
-//    This is a simple example that demonstrates generating a mipmap chain
-//    and rendering with it
-//
-#include <stdlib.h>
-#include "esUtil.h"
-
-typedef struct
-{
-   // Handle to a program object
-   GLuint programObject;
-
-   // Attribute locations
-   GLint  positionLoc;
-   GLint  texCoordLoc;
-
-   // Sampler location
-   GLint samplerLoc;
-
-   // Offset location
-   GLint offsetLoc;
-
-   // Texture handle
-   GLuint textureId;
-
-} UserData;
-
-
-///
-//  From an RGB8 source image, generate the next level mipmap
-//
-GLboolean GenMipMap2D( GLubyte *src, GLubyte **dst, int srcWidth, int srcHeight, int *dstWidth, int *dstHeight )
-{
-   int x,
-       y;
-   int texelSize = 3;
-
-   *dstWidth = srcWidth / 2;
-   if ( *dstWidth <= 0 )
-      *dstWidth = 1;
-
-   *dstHeight = srcHeight / 2;
-   if ( *dstHeight <= 0 )
-      *dstHeight = 1;
-
-   *dst = malloc ( sizeof(GLubyte) * texelSize * (*dstWidth) * (*dstHeight) );
-   if ( *dst == NULL )
-      return GL_FALSE;
-
-   for ( y = 0; y < *dstHeight; y++ )
-   {
-      for( x = 0; x < *dstWidth; x++ )
-      {
-         int srcIndex[4];
-         float r = 0.0f,
-               g = 0.0f,
-               b = 0.0f;
-         int sample;
-
-         // Compute the offsets for 2x2 grid of pixels in previous
-         // image to perform box filter
-         srcIndex[0] = 
-            (((y * 2) * srcWidth) + (x * 2)) * texelSize;
-         srcIndex[1] = 
-            (((y * 2) * srcWidth) + (x * 2 + 1)) * texelSize; 
-         srcIndex[2] = 
-            ((((y * 2) + 1) * srcWidth) + (x * 2)) * texelSize;
-         srcIndex[3] = 
-            ((((y * 2) + 1) * srcWidth) + (x * 2 + 1)) * texelSize;
-
-         // Sum all pixels
-         for ( sample = 0; sample < 4; sample++ )
-         {
-            r += src[srcIndex[sample]];
-            g += src[srcIndex[sample] + 1];
-            b += src[srcIndex[sample] + 2];
-         }
-
-         // Average results
-         r /= 4.0;
-         g /= 4.0;
-         b /= 4.0;
-
-         // Store resulting pixels
-         (*dst)[ ( y * (*dstWidth) + x ) * texelSize ] = (GLubyte)( r );
-         (*dst)[ ( y * (*dstWidth) + x ) * texelSize + 1] = (GLubyte)( g );
-         (*dst)[ ( y * (*dstWidth) + x ) * texelSize + 2] = (GLubyte)( b );
-      }
-   }
-
-   return GL_TRUE;
-}
-
-///
-//  Generate an RGB8 checkerboard image
-//
-GLubyte* GenCheckImage( int width, int height, int checkSize )
-{
-   int x,
-       y;
-   GLubyte *pixels = malloc( width * height * 3 );
-   
-   if ( pixels == NULL )
-      return NULL;
-
-   for ( y = 0; y < height; y++ )
-      for ( x = 0; x < width; x++ )
-      {
-         GLubyte rColor = 0;
-         GLubyte bColor = 0;
-
-         if ( ( x / checkSize ) % 2 == 0 )
-         {
-            rColor = 255 * ( ( y / checkSize ) % 2 );
-            bColor = 255 * ( 1 - ( ( y / checkSize ) % 2 ) );
-         }
-         else
-         {
-            bColor = 255 * ( ( y / checkSize ) % 2 );
-            rColor = 255 * ( 1 - ( ( y / checkSize ) % 2 ) );
-         }
-
-         pixels[(y * height + x) * 3] = rColor;
-         pixels[(y * height + x) * 3 + 1] = 0;
-         pixels[(y * height + x) * 3 + 2] = bColor; 
-      } 
-
-   return pixels;
-}
-
-///
-// Create a mipmapped 2D texture image 
-//
-GLuint CreateMipMappedTexture2D( )
-{
-   // Texture object handle
-   GLuint textureId;
-   int    width = 256,
-          height = 256;
-   int    level;
-   GLubyte *pixels;
-   GLubyte *prevImage;
-   GLubyte *newImage;
-      
-   pixels = GenCheckImage( width, height, 8 );
-   if ( pixels == NULL )
-      return 0;
-
-   // Generate a texture object
-   glGenTextures ( 1, &textureId );
-
-   // Bind the texture object
-   glBindTexture ( GL_TEXTURE_2D, textureId );
-
-   // Load mipmap level 0
-   glTexImage2D ( GL_TEXTURE_2D, 0, GL_RGB, width, height, 
-                  0, GL_RGB, GL_UNSIGNED_BYTE, pixels );
-   
-   level = 1;
-   prevImage = &pixels[0];
-   
-   while ( width > 1 && height > 1 )
-   {
-      int newWidth,
-          newHeight;
-
-      // Generate the next mipmap level
-      GenMipMap2D( prevImage, &newImage, width, height, 
-                   &newWidth, &newHeight );
-
-      // Load the mipmap level
-      glTexImage2D( GL_TEXTURE_2D, level, GL_RGB, 
-                    newWidth, newHeight, 0, GL_RGB,
-                    GL_UNSIGNED_BYTE, newImage );
-
-      // Free the previous image
-      free ( prevImage );
-
-      // Set the previous image for the next iteration
-      prevImage = newImage;
-      level++;
-
-      // Half the width and height
-      width = newWidth;
-      height = newHeight;
-   }
-
-   free ( newImage );
-
-   // Set the filtering mode
-   glTexParameteri ( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST_MIPMAP_NEAREST );
-   glTexParameteri ( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );
-
-   return textureId;
-
-}
-
-
-///
-// Initialize the shader and program object
-//
-int Init ( ESContext *esContext )
-{
-   UserData *userData = esContext->userData;
-   GLbyte vShaderStr[] =
-      "uniform float u_offset;      \n"
-      "attribute vec4 a_position;   \n"
-      "attribute vec2 a_texCoord;   \n"
-      "varying vec2 v_texCoord;     \n"
-      "void main()                  \n"
-      "{                            \n"
-      "   gl_Position = a_position; \n"
-      "   gl_Position.x += u_offset;\n"
-      "   v_texCoord = a_texCoord;  \n"
-      "}                            \n";
-   
-   GLbyte fShaderStr[] =  
-      "precision mediump float;                            \n"
-      "varying vec2 v_texCoord;                            \n"
-      "uniform sampler2D s_texture;                        \n"
-      "void main()                                         \n"
-      "{                                                   \n"
-      "  gl_FragColor = texture2D( s_texture, v_texCoord );\n"
-      "}                                                   \n";
-
-   // Load the shaders and get a linked program object
-   userData->programObject = esLoadProgram ( vShaderStr, fShaderStr );
-
-   // Get the attribute locations
-   userData->positionLoc = glGetAttribLocation ( userData->programObject, "a_position" );
-   userData->texCoordLoc = glGetAttribLocation ( userData->programObject, "a_texCoord" );
-   
-   // Get the sampler location
-   userData->samplerLoc = glGetUniformLocation ( userData->programObject, "s_texture" );
-
-   // Get the offset location
-   userData->offsetLoc = glGetUniformLocation( userData->programObject, "u_offset" );
-
-   // Load the texture
-   userData->textureId = CreateMipMappedTexture2D ();
-
-   glClearColor ( 0.0f, 0.0f, 0.0f, 0.0f );
-   return TRUE;
-}
-
-///
-// Draw a triangle using the shader pair created in Init()
-//
-void Draw ( ESContext *esContext )
-{
-   UserData *userData = esContext->userData;
-   GLfloat vVertices[] = { -0.5f,  0.5f, 0.0f, 1.5f,  // Position 0
-                            0.0f,  0.0f,              // TexCoord 0 
-                           -0.5f, -0.5f, 0.0f, 0.75f, // Position 1
-                            0.0f,  1.0f,              // TexCoord 1
-                            0.5f, -0.5f, 0.0f, 0.75f, // Position 2
-                            1.0f,  1.0f,              // TexCoord 2
-                            0.5f,  0.5f, 0.0f, 1.5f,  // Position 3
-                            1.0f,  0.0f               // TexCoord 3
-                         };
-   GLushort indices[] = { 0, 1, 2, 0, 2, 3 };
-      
-   // Set the viewport
-   glViewport ( 0, 0, esContext->width, esContext->height );
-   
-   // Clear the color buffer
-   glClear ( GL_COLOR_BUFFER_BIT );
-
-   // Use the program object
-   glUseProgram ( userData->programObject );
-
-   // Load the vertex position
-   glVertexAttribPointer ( userData->positionLoc, 4, GL_FLOAT, 
-                           GL_FALSE, 6 * sizeof(GLfloat), vVertices );
-   // Load the texture coordinate
-   glVertexAttribPointer ( userData->texCoordLoc, 2, GL_FLOAT,
-                           GL_FALSE, 6 * sizeof(GLfloat), &vVertices[4] );
-
-   glEnableVertexAttribArray ( userData->positionLoc );
-   glEnableVertexAttribArray ( userData->texCoordLoc );
-
-   // Bind the texture
-   glActiveTexture ( GL_TEXTURE0 );
-   glBindTexture ( GL_TEXTURE_2D, userData->textureId );
-
-   // Set the sampler texture unit to 0
-   glUniform1i ( userData->samplerLoc, 0 );
-
-   // Draw quad with nearest sampling
-   glTexParameteri ( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST );
-   glUniform1f ( userData->offsetLoc, -0.6f );   
-   glDrawElements ( GL_TRIANGLES, 6, GL_UNSIGNED_SHORT, indices );
-
-   // Draw quad with trilinear filtering
-   glTexParameteri ( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR );
-   glUniform1f ( userData->offsetLoc, 0.6f );
-   glDrawElements ( GL_TRIANGLES, 6, GL_UNSIGNED_SHORT, indices );
-
-   eglSwapBuffers ( esContext->eglDisplay, esContext->eglSurface );
-}
-
-///
-// Cleanup
-//
-void ShutDown ( ESContext *esContext )
-{
-   UserData *userData = esContext->userData;
-
-   // Delete texture object
-   glDeleteTextures ( 1, &userData->textureId );
-
-   // Delete program object
-   glDeleteProgram ( userData->programObject );
-}
-
-
-int main ( int argc, char *argv[] )
-{
-   ESContext esContext;
-   UserData  userData;
-
-   esInitContext ( &esContext );
-   esContext.userData = &userData;
-
-   esCreateWindow ( &esContext, "MipMap 2D", 320, 240, ES_WINDOW_RGB );
-   
-   if ( !Init ( &esContext ) )
-      return 0;
-
-   esRegisterDrawFunc ( &esContext, Draw );
-   
-   esMainLoop ( &esContext );
-
-   ShutDown ( &esContext );
-}