Index: third_party/gles_book_examples/Chapter_9/TextureWrap/TextureWrap.c |
=================================================================== |
--- third_party/gles_book_examples/Chapter_9/TextureWrap/TextureWrap.c (revision 35873) |
+++ third_party/gles_book_examples/Chapter_9/TextureWrap/TextureWrap.c (working copy) |
@@ -1,254 +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 |
-// |
- |
-// TextureWrap.c |
-// |
-// This is an example that demonstrates the three texture |
-// wrap modes available on 2D textures |
-// |
-#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; |
- |
-/// |
-// 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 CreateTexture2D( ) |
-{ |
- // Texture object handle |
- GLuint textureId; |
- int width = 256, |
- height = 256; |
- GLubyte *pixels; |
- |
- pixels = GenCheckImage( width, height, 64 ); |
- 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 ); |
- |
- // Set the filtering mode |
- glTexParameteri ( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR ); |
- 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 = CreateTexture2D (); |
- |
- 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[] = { -0.3f, 0.3f, 0.0f, 1.0f, // Position 0 |
- -1.0f, -1.0f, // TexCoord 0 |
- -0.3f, -0.3f, 0.0f, 1.0f, // Position 1 |
- -1.0f, 2.0f, // TexCoord 1 |
- 0.3f, -0.3f, 0.0f, 1.0f, // Position 2 |
- 2.0f, 2.0f, // TexCoord 2 |
- 0.3f, 0.3f, 0.0f, 1.0f, // Position 3 |
- 2.0f, -1.0f // 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 repeat wrap mode |
- glTexParameteri ( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT ); |
- glTexParameteri ( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT ); |
- glUniform1f ( userData->offsetLoc, -0.7f ); |
- glDrawElements ( GL_TRIANGLES, 6, GL_UNSIGNED_SHORT, indices ); |
- |
- // Draw quad with clamp to edge wrap mode |
- glTexParameteri ( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE ); |
- glTexParameteri ( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE ); |
- glUniform1f ( userData->offsetLoc, 0.0f ); |
- glDrawElements ( GL_TRIANGLES, 6, GL_UNSIGNED_SHORT, indices ); |
- |
- // Draw quad with mirrored repeat |
- glTexParameteri ( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_MIRRORED_REPEAT ); |
- glTexParameteri ( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_MIRRORED_REPEAT ); |
- glUniform1f ( userData->offsetLoc, 0.7f ); |
- 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", 640, 480, ES_WINDOW_RGB ); |
- |
- if ( !Init ( &esContext ) ) |
- return 0; |
- |
- esRegisterDrawFunc ( &esContext, Draw ); |
- |
- esMainLoop ( &esContext ); |
- |
- ShutDown ( &esContext ); |
-} |