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

third_party/gles_book_examples/Chapter_13/ParticleSystem/ParticleSystem.c

Index: third_party/gles_book_examples/Chapter_13/ParticleSystem/ParticleSystem.c
===================================================================
--- third_party/gles_book_examples/Chapter_13/ParticleSystem/ParticleSystem.c	(revision 35873)
+++ third_party/gles_book_examples/Chapter_13/ParticleSystem/ParticleSystem.c	(working copy)
@@ -1,294 +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
-//
-
-// ParticleSystem.c
-//
-//    This is an example that demonstrates rendering a particle system
-//    using a vertex shader and point sprites.
-//
-#include <stdlib.h>
-#include <math.h>
-#include "esUtil.h"
-
-#define NUM_PARTICLES	1000
-#define PARTICLE_SIZE   7
-
-typedef struct
-{
-   // Handle to a program object
-   GLuint programObject;
-
-   // Attribute locations
-   GLint  lifetimeLoc;
-   GLint  startPositionLoc;
-   GLint  endPositionLoc;
-   
-   // Uniform location
-   GLint timeLoc;
-   GLint colorLoc;
-   GLint centerPositionLoc;
-   GLint samplerLoc;
-
-   // Texture handle
-   GLuint textureId;
-
-   // Particle vertex data
-   float particleData[ NUM_PARTICLES * PARTICLE_SIZE ];
-
-   // Current time
-   float time;
-
-} UserData;
-
-///
-// Load texture from disk
-//
-GLuint LoadTexture ( char *fileName )
-{
-   int width,
-       height;
-   char *buffer = esLoadTGA ( fileName, &width, &height );
-   GLuint texId;
-
-   if ( buffer == NULL )
-   {
-      esLogMessage ( "Error loading (%s) image.\n", fileName );
-      return 0;
-   }
-
-   glGenTextures ( 1, &texId );
-   glBindTexture ( GL_TEXTURE_2D, texId );
-
-   glTexImage2D ( GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, buffer );
-   glTexParameteri ( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR );
-   glTexParameteri ( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );
-   glTexParameteri ( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE );
-   glTexParameteri ( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE );
-
-   free ( buffer );
-
-   return texId;
-}
-
-
-///
-// Initialize the shader and program object
-//
-int Init ( ESContext *esContext )
-{
-   UserData *userData = esContext->userData;
-   int i;
-   
-   GLbyte vShaderStr[] =
-      "uniform float u_time;		                           \n"
-      "uniform vec3 u_centerPosition;                       \n"
-      "attribute float a_lifetime;                          \n"
-      "attribute vec3 a_startPosition;                      \n"
-      "attribute vec3 a_endPosition;                        \n"
-      "varying float v_lifetime;                            \n"
-      "void main()                                          \n"
-      "{                                                    \n"
-      "  if ( u_time <= a_lifetime )                        \n"
-      "  {                                                  \n"
-      "    gl_Position.xyz = a_startPosition +              \n"
-      "                      (u_time * a_endPosition);      \n"
-      "    gl_Position.xyz += u_centerPosition;             \n"
-      "    gl_Position.w = 1.0;                             \n"
-      "  }                                                  \n"
-      "  else                                               \n"
-      "     gl_Position = vec4( -1000, -1000, 0, 0 );       \n"
-      "  v_lifetime = 1.0 - ( u_time / a_lifetime );        \n"
-      "  v_lifetime = clamp ( v_lifetime, 0.0, 1.0 );       \n"
-      "  gl_PointSize = ( v_lifetime * v_lifetime ) * 40.0; \n"
-      "}";
-      
-   GLbyte fShaderStr[] =  
-      "precision mediump float;                             \n"
-      "uniform vec4 u_color;		                           \n"
-      "varying float v_lifetime;                            \n"
-      "uniform sampler2D s_texture;                         \n"
-      "void main()                                          \n"
-      "{                                                    \n"
-      "  vec4 texColor;                                     \n"
-      "  texColor = texture2D( s_texture, gl_PointCoord );  \n"
-      "  gl_FragColor = vec4( u_color ) * texColor;         \n"
-      "  gl_FragColor.a *= v_lifetime;                      \n"
-      "}                                                    \n";
-
-   // Load the shaders and get a linked program object
-   userData->programObject = esLoadProgram ( vShaderStr, fShaderStr );
-
-   // Get the attribute locations
-   userData->lifetimeLoc = glGetAttribLocation ( userData->programObject, "a_lifetime" );
-   userData->startPositionLoc = glGetAttribLocation ( userData->programObject, "a_startPosition" );
-   userData->endPositionLoc = glGetAttribLocation ( userData->programObject, "a_endPosition" );
-   
-   // Get the uniform locations
-   userData->timeLoc = glGetUniformLocation ( userData->programObject, "u_time" );
-   userData->centerPositionLoc = glGetUniformLocation ( userData->programObject, "u_centerPosition" );
-   userData->colorLoc = glGetUniformLocation ( userData->programObject, "u_color" );
-   userData->samplerLoc = glGetUniformLocation ( userData->programObject, "s_texture" );
-
-   glClearColor ( 0.0f, 0.0f, 0.0f, 0.0f );
-
-   // Fill in particle data array
-   srand ( 0 );
-   for ( i = 0; i < NUM_PARTICLES; i++ )
-   {
-      float *particleData = &userData->particleData[i * PARTICLE_SIZE];
-   
-      // Lifetime of particle
-      (*particleData++) = ( (float)(rand() % 10000) / 10000.0f );
-
-      // End position of particle
-      (*particleData++) = ( (float)(rand() % 10000) / 5000.0f ) - 1.0f;
-      (*particleData++) = ( (float)(rand() % 10000) / 5000.0f ) - 1.0f;
-      (*particleData++) = ( (float)(rand() % 10000) / 5000.0f ) - 1.0f;
-
-      // Start position of particle
-      (*particleData++) = ( (float)(rand() % 10000) / 40000.0f ) - 0.125f;
-      (*particleData++) = ( (float)(rand() % 10000) / 40000.0f ) - 0.125f;
-      (*particleData++) = ( (float)(rand() % 10000) / 40000.0f ) - 0.125f;
-
-   }
-
-   // Initialize time to cause reset on first update
-   userData->time = 1.0f;
-
-   userData->textureId = LoadTexture ( "smoke.tga" );
-   if ( userData->textureId <= 0 )
-   {
-      return FALSE;
-   }
-   
-   return TRUE;
-}
-
-///
-//  Update time-based variables
-//
-void Update ( ESContext *esContext, float deltaTime )
-{
-   UserData *userData = esContext->userData;
-  
-   userData->time += deltaTime;
-
-   if ( userData->time >= 1.0f )
-   {
-      float centerPos[3];
-      float color[4];
-
-      userData->time = 0.0f;
-
-      // Pick a new start location and color
-      centerPos[0] = ( (float)(rand() % 10000) / 10000.0f ) - 0.5f;
-      centerPos[1] = ( (float)(rand() % 10000) / 10000.0f ) - 0.5f;
-      centerPos[2] = ( (float)(rand() % 10000) / 10000.0f ) - 0.5f;
-      
-      glUniform3fv ( userData->centerPositionLoc, 1, &centerPos[0] );
-
-      // Random color
-      color[0] = ( (float)(rand() % 10000) / 20000.0f ) + 0.5f;
-      color[1] = ( (float)(rand() % 10000) / 20000.0f ) + 0.5f;
-      color[2] = ( (float)(rand() % 10000) / 20000.0f ) + 0.5f;
-      color[3] = 0.5;
-
-      glUniform4fv ( userData->colorLoc, 1, &color[0] );
-   }
-
-   // Load uniform time variable
-   glUniform1f ( userData->timeLoc, userData->time );
-}
-
-///
-// Draw a triangle using the shader pair created in Init()
-//
-void Draw ( ESContext *esContext )
-{
-   UserData *userData = esContext->userData;
-      
-   // 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 attributes
-   glVertexAttribPointer ( userData->lifetimeLoc, 1, GL_FLOAT, 
-                           GL_FALSE, PARTICLE_SIZE * sizeof(GLfloat), 
-                           userData->particleData );
-   
-   glVertexAttribPointer ( userData->endPositionLoc, 3, GL_FLOAT,
-                           GL_FALSE, PARTICLE_SIZE * sizeof(GLfloat),
-                           &userData->particleData[1] );
-
-   glVertexAttribPointer ( userData->startPositionLoc, 3, GL_FLOAT,
-                           GL_FALSE, PARTICLE_SIZE * sizeof(GLfloat),
-                           &userData->particleData[4] );
-
-   
-   glEnableVertexAttribArray ( userData->lifetimeLoc );
-   glEnableVertexAttribArray ( userData->endPositionLoc );
-   glEnableVertexAttribArray ( userData->startPositionLoc );
-   // Blend particles
-   glEnable ( GL_BLEND );
-   glBlendFunc ( GL_SRC_ALPHA, GL_ONE );
-
-   // Bind the texture
-   glActiveTexture ( GL_TEXTURE0 );
-   glBindTexture ( GL_TEXTURE_2D, userData->textureId );
-   glEnable ( GL_TEXTURE_2D );
-
-   // Set the sampler texture unit to 0
-   glUniform1i ( userData->samplerLoc, 0 );
-
-   glDrawArrays( GL_POINTS, 0, NUM_PARTICLES );
-   
-   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, "ParticleSystem", 640, 480, ES_WINDOW_RGB );
-   
-   if ( !Init ( &esContext ) )
-      return 0;
-
-   esRegisterDrawFunc ( &esContext, Draw );
-   esRegisterUpdateFunc ( &esContext, Update );
-   
-   esMainLoop ( &esContext );
-
-   ShutDown ( &esContext );
-}