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/* platform.c
*
* Platform
*
*
*/
#include <SDL/SDL.h>
#include <SDL/SDL_image.h>
#include <GL/glew.h>
#include "platform.h"
/* few light arrays */
GLfloat fNoLight[] = { 0.0f, 0.0f, 0.0f, 0.0f };
GLfloat fLowLight[] = { 0.25f, 0.25f, 0.25f, 1.0f };
GLfloat fMedLight[] = { 0.50f, 0.50f, 0.50f, 1.0f };
GLfloat fBrightLight[] = { 1.0f, 1.0f, 1.0f, 1.0f };
/* light values and coordinates */
GLfloat whiteLight[] = { 0.05f, 0.05f, 0.05f, 1.0f };
GLfloat sourceLight[] = { 0.75f, 0.75f, 0.75f, 1.0f };
GLfloat lightPos[] = { -10.f, 5.0f, 5.0f, 1.0f };
/* variables that should be already defined and declared for us by main program */
extern const unsigned int xres_w;
extern const unsigned int yres_w;
extern const unsigned int bpp_w;
extern const unsigned int sdl_video_flags;
extern const char *window_caption;
extern const char *window_icon_path;
void setup_opengl(void)
{
/* setup fog */
glEnable(GL_FOG);
glFogfv(GL_FOG_COLOR, fLowLight); /* set fog color to match background */
glFogf(GL_FOG_START, 4.0f);
glFogf(GL_FOG_END, 20.0f);
glFogi(GL_FOG_MODE, GL_LINEAR); /* fog equation */
glEnable(GL_DEPTH_TEST); /* hidden surface removal */
glFrontFace(GL_CCW); /* counter clock-wise polygons face out */
glEnable(GL_CULL_FACE); /* do not calculate inside of a pyramid */
/* enable lighting */
glEnable(GL_LIGHTING);
/* global illumination, ambient RGBA intensity of the entire scene */
glLightModelfv(GL_LIGHT_MODEL_AMBIENT, fLowLight);
/* setup and enable light 0 */
glLightfv(GL_LIGHT0, GL_AMBIENT, fMedLight);
glLightfv(GL_LIGHT0, GL_DIFFUSE, fMedLight);
glLightfv(GL_LIGHT0, GL_SPECULAR, fBrightLight);
glLightfv(GL_LIGHT0, GL_POSITION, lightPos);
glEnable(GL_LIGHT0);
/* enable color tracking */
glEnable(GL_COLOR_MATERIAL);
/* set material properties to follow glColor values */
/* all primitives specified after the glMaterial call are affected by the
* last values set, until another call to glMaterial is made */
glColorMaterial(GL_FRONT, GL_AMBIENT_AND_DIFFUSE);
glMaterialfv(GL_FRONT, GL_SPECULAR, fBrightLight);
glMateriali(GL_FRONT, GL_SHININESS, 128);
/* turn on anti aliasing for points, lines, and polygons */
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glEnable(GL_BLEND);
glEnable(GL_POINT_SMOOTH);
glHint(GL_POINT_SMOOTH_HINT, GL_NICEST);
glEnable(GL_LINE_SMOOTH);
glHint(GL_LINE_SMOOTH_HINT, GL_NICEST);
/* screws up snowman, this has been replaced by superior multisampling */
//glEnable(GL_POLYGON_SMOOTH);
//glHint(GL_POLYGON_SMOOTH_HINT, GL_NICEST);
/* multisampling for polygons, conflicts with *polygon* anti-aliasing */
glEnable(GL_MULTISAMPLE);
/* how OpenGL combines the colors from texels with the color of the underlying
* geometry is controlled by the texture environment mode */
glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
/* once texture is loaded and enabled, it will applied to every primitive
* that specifies coordinates, ORLY? */
glEnable(GL_TEXTURE_2D);
/* don't know about this, but why not */
glLightModeli(GL_LIGHT_MODEL_COLOR_CONTROL, GL_SEPARATE_SPECULAR_COLOR);
/* gray background */
glClearColor(0.5f, 0.5f, 0.5f, 1.0f);
}
SDL_Surface *setup_sdl_video(int w, int h, int bpp, unsigned int flags)
{
SDL_Surface *srfc;
if (!bpp)
{
const SDL_VideoInfo* info = NULL;
/* get some video information. */
info = SDL_GetVideoInfo();
if (!info)
{
fprintf( stderr, "SDL: video query failed: %s\n", SDL_GetError());
exit(-1);
}
bpp = info->vfmt->BitsPerPixel;
printf("SDL: bpp was not specified, chose %d bits\n", bpp);
}
if (!flags)
flags = SDL_OPENGL | SDL_RESIZABLE;
if ((srfc = SDL_SetVideoMode(w, h, bpp, flags)) == NULL)
{
fprintf(stderr, "SDL: unable to set video mode: %s\n", SDL_GetError());
exit(-1);
}
return srfc;
}
void setup_sdl(void)
{
SDL_Surface *screen;
const SDL_VideoInfo* info = NULL;
if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_AUDIO | SDL_INIT_TIMER) == -1)
{
fprintf(stderr, "SDL: unable to init, %s\n", SDL_GetError());
exit(-1);
}
atexit(SDL_Quit);
SDL_GL_SetAttribute(SDL_GL_RED_SIZE, 8);
SDL_GL_SetAttribute(SDL_GL_GREEN_SIZE, 8);
SDL_GL_SetAttribute(SDL_GL_BLUE_SIZE, 8);
SDL_GL_SetAttribute(SDL_GL_ALPHA_SIZE, 8);
SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 24);
SDL_WM_SetCaption(window_caption, NULL);
SDL_WM_SetIcon(IMG_Load(window_icon_path), NULL);
/* set video mode */
screen = setup_sdl_video(xres_w, yres_w, bpp_w, sdl_video_flags);
/* get some video information. */
info = SDL_GetVideoInfo();
if (!info)
{
fprintf( stderr, "SDL: video query failed: %s\n", SDL_GetError());
exit(-1);
}
int bpp = info->vfmt->BitsPerPixel;
printf("SDL: applied %d bits per pixel\n", bpp);
/* query opengl attributes after SetVideoMode call */
int fb_red_comp;
int fb_green_comp;
int fb_blue_comp;
int fb_alpha_comp;
int double_buff;
int depth_sz;
SDL_GL_GetAttribute(SDL_GL_RED_SIZE, &fb_red_comp);
SDL_GL_GetAttribute(SDL_GL_GREEN_SIZE, &fb_green_comp);
SDL_GL_GetAttribute(SDL_GL_BLUE_SIZE, &fb_blue_comp);
SDL_GL_GetAttribute(SDL_GL_ALPHA_SIZE, &fb_alpha_comp);
SDL_GL_GetAttribute(SDL_GL_DOUBLEBUFFER, &double_buff);
SDL_GL_GetAttribute(SDL_GL_DEPTH_SIZE, &depth_sz);
printf("SDL: framebuffer; size of components, red: %d bits, green: %d bits, "
"blue: %d bits, alpha: %d bits\n"
"SDL: double-buffering: %s, depth buffer size: %d bits\n",
fb_red_comp, fb_green_comp, fb_blue_comp, fb_alpha_comp,
double_buff ? "enabled" : "disabled", depth_sz);
SDL_EnableUNICODE(1);
/* SDL doesn't trigger off a ResizeEvent at startup, but as we need this
* for OpenGL, we do this ourselves */
SDL_Event resizeEvent;
resizeEvent.type = SDL_VIDEORESIZE;
resizeEvent.resize.w = xres_w;
resizeEvent.resize.h = yres_w;
SDL_PushEvent(&resizeEvent);
/* save the surf pointer in platform */
}
void setup_glew(void)
{
/* initalize glew */
GLenum glewerr = glewInit();
if (GLEW_OK != glewerr)
{
fprintf(stderr, "GLEW error: %s\n", glewGetErrorString(glewerr));
exit(-1);
}
else
fprintf(stdout, "GLEW: using version %s\n", glewGetString(GLEW_VERSION));
/* display OpenGL version */
GLint major;
GLint minor;
glGetIntegerv(GL_MAJOR_VERSION, &major);
glGetIntegerv(GL_MINOR_VERSION, &minor);
fprintf(stdout, "GLEW: detected OpenGL %d.%d\n", major, minor);
}
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