view test/testdyngl.c @ 1768:814f9f2c7a33

Fixed bug #80 Date: 21 Apr 2003 17:20:20 +0100 From: Alan Swanson <swanson@uklinux.net> Subject: [SDL] New XFree 4.3 Video Mode Patch If you look at the unsorted list of modes returned by X, here's mine; 1280 x 1024 @ 85.0 > 1024 x 768 @ 100.3 > USER 800 x 600 @ 125.5 > SET 640 x 480 @ 124.9 > 1280 x 1024 @ 75.0 ] 1280 x 1024 @ 60.0 ] 1280 x 960 @ 85.0 ] X11 1280 x 960 @ 60.0 ] AUTO 1152 x 864 @ 75.0 ]=20 1152 x 768 @ 54.8 ] 960 x 720 @ 120.0 ] ... 640 x 400 @ 85.1 ] 256k 576 x 432 @ 150.0 ] 249k PIXEL 640 x 350 @ 85.1 ] 224k COUNT 576 x 384 @ 109.6 ] 221k ... The user set modes come first followed by X set modes which are ordered by decreasing number of pixels and refresh. The reason why every other library or program not using SDL working is due to SDL scanning the modes in reverse getting X11 provided modes modes with the lowest refresh.
author Sam Lantinga <slouken@libsdl.org>
date Fri, 05 May 2006 05:50:26 +0000
parents ae78374ac894
children 14717b52abc0
line wrap: on
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/*
 * Small SDL example to demonstrate dynamically loading 
 * OpenGL lib and functions
 *
 * (FYI it was supposed to look like snow in the wind or something...)
 *
 * Compile with :
 * gcc testdyngl.c `sdl-config --libs --cflags` -o testdyngl -DHAVE_OPENGL
 *
 * You can specify a different OpenGL lib on the command line, i.e. :
 * ./testdyngl  /usr/X11R6/lib/libGL.so.1.2
 * or
 * ./testdyngl  /usr/lib/libGL.so.1.0.4496
 *
 */

#include <stdio.h>
#include <stdlib.h>

#include "SDL.h"

#ifdef HAVE_OPENGL

#include "SDL_opengl.h"

/* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */
static void quit(int rc)
{
	SDL_Quit();
	exit(rc);
}

void* get_funcaddr(const char* p)
{
	void* f=SDL_GL_GetProcAddress(p);
	if (f)
	{
		return f;
	}
	else
	{
		printf("Unable to get function pointer for %s\n",p);
		quit(1);
	}
	return NULL;
}

typedef struct
{
	void(APIENTRY*glBegin)(GLenum);
	void(APIENTRY*glEnd)();
	void(APIENTRY*glVertex3f)(GLfloat, GLfloat, GLfloat);
	void(APIENTRY*glClearColor)(GLfloat, GLfloat, GLfloat, GLfloat);
	void(APIENTRY*glClear)(GLbitfield);
	void(APIENTRY*glDisable)(GLenum);
	void(APIENTRY*glEnable)(GLenum);
	void(APIENTRY*glColor4ub)(GLubyte,GLubyte,GLubyte,GLubyte);
	void(APIENTRY*glPointSize)(GLfloat);
	void(APIENTRY*glHint)(GLenum,GLenum);
	void(APIENTRY*glBlendFunc)(GLenum,GLenum);
	void(APIENTRY*glMatrixMode)(GLenum);
	void(APIENTRY*glLoadIdentity)();
	void(APIENTRY*glOrtho)(GLdouble,GLdouble,GLdouble,GLdouble,GLdouble,GLdouble);
	void(APIENTRY*glRotatef)(GLfloat,GLfloat,GLfloat,GLfloat);
	void(APIENTRY*glViewport)(GLint,GLint,GLsizei,GLsizei);
	void(APIENTRY*glFogf)(GLenum,GLfloat);
}
glfuncs;

void init_glfuncs(glfuncs* f)
{
	f->glBegin=get_funcaddr("glBegin");
	f->glEnd=get_funcaddr("glEnd");
	f->glVertex3f=get_funcaddr("glVertex3f");
	f->glClearColor=get_funcaddr("glClearColor");
	f->glClear=get_funcaddr("glClear");
	f->glDisable=get_funcaddr("glDisable");
	f->glEnable=get_funcaddr("glEnable");
	f->glColor4ub=get_funcaddr("glColor4ub");
	f->glPointSize=get_funcaddr("glPointSize");
	f->glHint=get_funcaddr("glHint");
	f->glBlendFunc=get_funcaddr("glBlendFunc");
	f->glMatrixMode=get_funcaddr("glMatrixMode");
	f->glLoadIdentity=get_funcaddr("glLoadIdentity");
	f->glOrtho=get_funcaddr("glOrtho");
	f->glRotatef=get_funcaddr("glRotatef");
	f->glViewport=get_funcaddr("glViewport");
	f->glFogf=get_funcaddr("glFogf");
}

#define NB_PIXELS 1000

int main(int argc,char *argv[])
{
	glfuncs f;
	int i;
	SDL_Event event;
	int done=0;
	GLfloat pixels[NB_PIXELS*3];
	const char *gl_library = NULL; /* Use the default GL library */

	if (argv[1]) {
		gl_library = argv[1];
	}
	
	if (SDL_Init(SDL_INIT_VIDEO)<0)
	{
		printf("Unable to init SDL : %s\n",SDL_GetError());
		return(1);
	}

	if (SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER,1)<0)
	{
		printf("Unable to set GL attribute : %s\n",SDL_GetError());
		quit(1);
	}
	
	if (SDL_GL_LoadLibrary(gl_library)<0)
	{
		printf("Unable to dynamically open GL lib : %s\n",SDL_GetError());
		quit(1);
	}

	if (SDL_SetVideoMode(640,480,0,SDL_OPENGL)==NULL)
	{
		printf("Unable to open video mode : %s\n",SDL_GetError());
		quit(1);
	}

	/* Set the window manager title bar */
	SDL_WM_SetCaption( "SDL Dynamic OpenGL Loading Test", "testdyngl" );

	init_glfuncs(&f);

	for(i=0;i<NB_PIXELS;i++)
	{
		pixels[3*i]=rand()%250-125;
		pixels[3*i+1]=rand()%250-125;
		pixels[3*i+2]=rand()%250-125;
	}
	
	f.glViewport(0,0,640,480);
	
	f.glMatrixMode(GL_PROJECTION);
	f.glLoadIdentity();
	f.glOrtho(-100,100,-100,100,-500,500);
	
	f.glMatrixMode(GL_MODELVIEW);
	f.glLoadIdentity();
	
	f.glEnable(GL_DEPTH_TEST);
	f.glDisable(GL_TEXTURE_2D);
	f.glEnable(GL_BLEND);
	f.glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
	
	f.glClearColor(0.0f,0.0f,0.0f,0.0f);
	f.glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
	
	f.glEnable(GL_POINT_SMOOTH);
	f.glHint(GL_POINT_SMOOTH_HINT,GL_NICEST);
	f.glPointSize(5.0f);
	f.glEnable(GL_FOG);
	f.glFogf(GL_FOG_START,-500);
	f.glFogf(GL_FOG_END,500);
	f.glFogf(GL_FOG_DENSITY,0.005);
	
	do
	{
		f.glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
		
		f.glRotatef(2.0,1.0,1.0,1.0);
		f.glRotatef(1.0,0.0,1.0,1.0);
		
		f.glColor4ub(255,255,255,255);
		f.glBegin(GL_POINTS);
		for(i=0;i<NB_PIXELS;i++)
		{
			f.glVertex3f(pixels[3*i],pixels[3*i+1],pixels[3*i+2]);
		}
		f.glEnd();
		SDL_GL_SwapBuffers();

		while(SDL_PollEvent(&event))
		{
			if(event.type & SDL_KEYDOWN)
				done=1;
		}

		SDL_Delay(20);
	}
	while(!done);
	
	SDL_Quit();
	return 0;
}

#else /* HAVE_OPENGL */

int main(int argc, char *argv[])
{
	printf("No OpenGL support on this system\n");
	return 1;
}

#endif /* HAVE_OPENGL */