mirror of
https://gitlab.winehq.org/wine/wine-gecko.git
synced 2024-09-13 09:24:08 -07:00
214 lines
6.3 KiB
C
214 lines
6.3 KiB
C
//
|
|
// 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
|
|
//
|
|
|
|
// MultiTexture.c
|
|
//
|
|
// This is an example that draws a quad with a basemap and
|
|
// lightmap to demonstrate multitexturing.
|
|
//
|
|
#include <stdlib.h>
|
|
#include "esUtil.h"
|
|
|
|
typedef struct
|
|
{
|
|
// Handle to a program object
|
|
GLuint programObject;
|
|
|
|
// Attribute locations
|
|
GLint positionLoc;
|
|
GLint texCoordLoc;
|
|
|
|
// Sampler locations
|
|
GLint baseMapLoc;
|
|
GLint lightMapLoc;
|
|
|
|
// Texture handle
|
|
GLuint baseMapTexId;
|
|
GLuint lightMapTexId;
|
|
|
|
} 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;
|
|
GLbyte vShaderStr[] =
|
|
"attribute vec4 a_position; \n"
|
|
"attribute vec2 a_texCoord; \n"
|
|
"varying vec2 v_texCoord; \n"
|
|
"void main() \n"
|
|
"{ \n"
|
|
" gl_Position = a_position; \n"
|
|
" v_texCoord = a_texCoord; \n"
|
|
"} \n";
|
|
|
|
GLbyte fShaderStr[] =
|
|
"precision mediump float; \n"
|
|
"varying vec2 v_texCoord; \n"
|
|
"uniform sampler2D s_baseMap; \n"
|
|
"uniform sampler2D s_lightMap; \n"
|
|
"void main() \n"
|
|
"{ \n"
|
|
" vec4 baseColor; \n"
|
|
" vec4 lightColor; \n"
|
|
" \n"
|
|
" baseColor = texture2D( s_baseMap, v_texCoord ); \n"
|
|
" lightColor = texture2D( s_lightMap, v_texCoord ); \n"
|
|
" gl_FragColor = baseColor * (lightColor + 0.25); \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->baseMapLoc = glGetUniformLocation ( userData->programObject, "s_baseMap" );
|
|
userData->lightMapLoc = glGetUniformLocation ( userData->programObject, "s_lightMap" );
|
|
|
|
// Load the textures
|
|
userData->baseMapTexId = LoadTexture ( "basemap.tga" );
|
|
userData->lightMapTexId = LoadTexture ( "lightmap.tga" );
|
|
|
|
if ( userData->baseMapTexId == 0 || userData->lightMapTexId == 0 )
|
|
return FALSE;
|
|
|
|
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, // Position 0
|
|
0.0f, 0.0f, // TexCoord 0
|
|
-0.5f, -0.5f, 0.0f, // Position 1
|
|
0.0f, 1.0f, // TexCoord 1
|
|
0.5f, -0.5f, 0.0f, // Position 2
|
|
1.0f, 1.0f, // TexCoord 2
|
|
0.5f, 0.5f, 0.0f, // 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, 3, GL_FLOAT,
|
|
GL_FALSE, 5 * sizeof(GLfloat), vVertices );
|
|
// Load the texture coordinate
|
|
glVertexAttribPointer ( userData->texCoordLoc, 2, GL_FLOAT,
|
|
GL_FALSE, 5 * sizeof(GLfloat), &vVertices[3] );
|
|
|
|
glEnableVertexAttribArray ( userData->positionLoc );
|
|
glEnableVertexAttribArray ( userData->texCoordLoc );
|
|
|
|
// Bind the base map
|
|
glActiveTexture ( GL_TEXTURE0 );
|
|
glBindTexture ( GL_TEXTURE_2D, userData->baseMapTexId );
|
|
|
|
// Set the base map sampler to texture unit to 0
|
|
glUniform1i ( userData->baseMapLoc, 0 );
|
|
|
|
// Bind the light map
|
|
glActiveTexture ( GL_TEXTURE1 );
|
|
glBindTexture ( GL_TEXTURE_2D, userData->lightMapTexId );
|
|
|
|
// Set the light map sampler to texture unit 1
|
|
glUniform1i ( userData->lightMapLoc, 1 );
|
|
|
|
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->baseMapTexId );
|
|
glDeleteTextures ( 1, &userData->lightMapTexId );
|
|
|
|
// Delete program object
|
|
glDeleteProgram ( userData->programObject );
|
|
}
|
|
|
|
|
|
int main ( int argc, char *argv[] )
|
|
{
|
|
ESContext esContext;
|
|
UserData userData;
|
|
|
|
esInitContext ( &esContext );
|
|
esContext.userData = &userData;
|
|
|
|
esCreateWindow ( &esContext, TEXT("MultiTexture"), 320, 240, ES_WINDOW_RGB );
|
|
|
|
if ( !Init ( &esContext ) )
|
|
return 0;
|
|
|
|
esRegisterDrawFunc ( &esContext, Draw );
|
|
|
|
esMainLoop ( &esContext );
|
|
|
|
ShutDown ( &esContext );
|
|
}
|