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/*
THIS WORK, INCLUDING THE SOURCE CODE, DOCUMENTATION
AND RELATED MEDIA AND DATA, IS PLACED INTO THE PUBLIC DOMAIN.
THE ORIGINAL AUTHOR IS KYLE FOLEY.
THIS SOFTWARE IS PROVIDED AS-IS WITHOUT WARRANTY
OF ANY KIND, NOT EVEN THE IMPLIED WARRANTY OF
MERCHANTABILITY. THE AUTHOR OF THIS SOFTWARE,
ASSUMES _NO_ RESPONSIBILITY FOR ANY CONSEQUENCE
RESULTING FROM THE USE, MODIFICATION, OR
REDISTRIBUTION OF THIS SOFTWARE.
*/
#include "GL/glew.h"
#include "SDL/SDL.h"
#include "SDL/SDL_image.h"
#include <stdio.h>
#include <string.h>
int main(int argc, char *argv[])
{
SDL_Surface *screen;
if ( SDL_Init(SDL_INIT_VIDEO) != 0 ) {
printf("Unable to initialize SDL: %s\n", SDL_GetError());
return 1;
}
SDL_GL_SetAttribute( SDL_GL_DOUBLEBUFFER, 1 );
screen = SDL_SetVideoMode( 640, 480, 16, SDL_OPENGL );
if ( !screen ) {
printf("Unable to set video mode: %s\n", SDL_GetError());
return 1;
}
glClearColor( 0, 0, 0, 0 );
#if !EMSCRIPTEN
glEnable( GL_TEXTURE_2D ); // Need this to display a texture XXX unnecessary in OpenGL ES 2.0/WebGL
#endif
glViewport( 0, 0, 640, 480 );
glMatrixMode( GL_PROJECTION );
glLoadIdentity();
glOrtho( 0, 640, 480, 0, -1, 1 );
glMatrixMode( GL_MODELVIEW );
glLoadIdentity();
// Load the OpenGL texture
GLuint texture; // Texture object handle
SDL_Surface *surface; // Gives us the information to make the texture
if ( (surface = IMG_Load("screenshot.png")) ) {
// Check that the image's width is a power of 2
if ( (surface->w & (surface->w - 1)) != 0 ) {
printf("warning: image.bmp's width is not a power of 2\n");
}
// Also check if the height is a power of 2
if ( (surface->h & (surface->h - 1)) != 0 ) {
printf("warning: image.bmp's height is not a power of 2\n");
}
glGenTextures( 1, &texture );
glBindTexture( GL_TEXTURE_2D, texture );
glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR );
glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );urface gives us
glTexImage2D( GL_TEXTURE_2D, 0, GL_RGBA, surface->w, surface->h, 0,
GL_RGBA, GL_UNSIGNED_BYTE, surface->pixels );
}
else {
printf("SDL could not load image.bmp: %s\n", SDL_GetError());
SDL_Quit();
return 1;
}
if ( surface ) {
SDL_FreeSurface( surface );
}
glClear( GL_COLOR_BUFFER_BIT );
// BEGIN
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glFrustum(-0.6435469817188064, 0.6435469817188064 ,-0.48266022190470925, 0.48266022190470925 ,0.5400000214576721, 2048);
glMatrixMode(GL_MODELVIEW0);
GLfloat matrixData[] = { -1, 0, 0, 0,
0, 0,-1, 0,
0, 1, 0, 0,
0, 0, 0, 1 };
glLoadMatrixf(matrixData);
glRotated(0, 0, 1, 0);
glRotated(0,-1, 0, 0);
glRotated(0, 0, 0,-1);
glTranslated(-512,-512,-527);
glEnable(GL_CULL_FACE);
glEnable(GL_DEPTH_TEST);
glClear(GL_DEPTH_BUFFER_BIT);
glEnableClientState(GL_NORMAL_ARRAY);
glEnableClientState(GL_COLOR_ARRAY);
glEnableClientState(GL_TEXTURE_COORD_ARRAY);
glActiveTexture(GL_TEXTURE0);
glEnableClientState(GL_VERTEX_ARRAY);
glBindBuffer(GL_ARRAY_BUFFER, XXXXXXXXXXXXXXX);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, YYYYYYYYYYYYYYYY);
// sauer vertex data is apparently 0-12: V3F, 12: N1B, 16-24: T2F, 24-28: T2S, 28-32: C4B
glVertexPointer(3, GL_FLOAT, 32, 0); // all these apply to the ARRAY_BUFFER that is bound
glTexCoordPointer(2, GL_FLOAT ,32, 16);
glClientActiveTexture(GL_TEXTURE1);
glTexCoordPointer(2, GL_SHORT, 32, 24);
glClientActiveTexture(GL_TEXTURE0); // likely not needed, it is a cleanup
glNormalPointer(GL_BYTE, 32, 12);
glColorPointer(4, GL_UNSIGNED_BYTE, 32, 28);
glBindTexture(GL_TEXTURE_2D, texture); // diffuse?
glActiveTexture(GL_TEXTURE0);
glActiveTexture(GL_TEXTURE1);
glBindTexture(GL_TEXTURE_2D, texture); // lightmap? should be different
glActiveTexture(GL_TEXTURE0);
GLint ok;
char *vertexShader = "#pragma CUBE2_fog\n"
"uniform vec4 texgenscroll;\n"
"void main(void)\n"
"{\n"
" gl_Position = ftransform();\n"
" gl_TexCoord[0].xy = gl_MultiTexCoord0.xy + texgenscroll.xy;\n"
" gl_TexCoord[1].xy = gl_MultiTexCoord1.xy * 3.051851e-05;\n"
" #pragma CUBE2_shadowmap\n"
" #pragma CUBE2_dynlight\n"
" #pragma CUBE2_water\n"
"}\n";
char *fragmentShader = "uniform vec4 colorparams;\n"
"uniform sampler2D diffusemap, lightmap;\n"
"void main(void)\n"
"{\n"
" vec4 diffuse = texture2D(diffusemap, gl_TexCoord[0].xy);\n"
" vec4 lm = texture2D(lightmap, gl_TexCoord[1].xy);\n"
" #pragma CUBE2_shadowmap lm\n"
" #pragma CUBE2_dynlight lm\n"
" diffuse *= colorparams;\n"
" gl_FragColor = diffuse * lm;\n"
" #pragma CUBE2_water\n"
"}\n";
GLuint vs = glCreateShader(GL_VERTEX_SHADER);
glShaderSource(vs, 1, &vertexShader, NULL);
glCompileShader(vs);
glGetShaderiv(vs, GL_COMPILE_STATUS, &ok);
assert(ok);
GLuint fs = glCreateShader(GL_FRAGMENT_SHADER);
glShaderSource(fs, 1, &fragmentShader, NULL);
glCompileShader(fs);
GLint ok;
glGetShaderiv(fs, GL_COMPILE_STATUS, &ok);
assert(ok);
GLuint program = glCreateProgram();
glAttachShader(program, vs);
glAttachShader(program, fs);
glLinkProgram(program);
glGetProgramiv(program, GL_LINK_STATUS, &ok);
assert(ok);
glUseProgram(program);
GLint lightmapLocation = glGetUniformLocation(program, "lightmap");
assert(lightmapLocation >= 0);
glUniform1i(lightmapLocation, 1); // sampler2D? Is it the texture unit?
GLint diffusemapLocation = glGetUniformLocation(program, "diffusemap");
assert(diffusemapLocation >= 0);
glUniform1i(diffusemapLocation, 0); // sampler2D? Is it the texture unit?
GLint texgenscrollLocation = glGetUniformLocation(program, "texgenscroll");
assert(texgenscrollLocation >= 0);
GLint colorparamsLocation = glGetUniformLocation(program, "colorparams");
assert(colorparamsLocation >= 0);
GLfloat texgenscrollData[] = { 0, 0, 0, 0 };
glUniform4fv(texgenscrollLocation, 1, textgenscrollData);
GLfloat colorparamsData[] = { 2, 2, 2, 1 };
glUniform4fv(colorparamsLocation, 1, colorparamsData);
glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_SHORT, 12);
glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_SHORT, 0);
glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_SHORT, 24);
glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_SHORT, 36);
// END
SDL_GL_SwapBuffers();
#if !EMSCRIPTEN
// Wait for 3 seconds to give us a chance to see the image
SDL_Delay(3000);
#endif
// Now we can delete the OpenGL texture and close down SDL
glDeleteTextures( 1, &texture );
SDL_Quit();
return 0;
}
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