test/testdyngl.c
author Sam Lantinga <slouken@libsdl.org>
Sun, 18 Jul 2004 19:46:38 +0000
changeset 910 4ab6d1fd028f
parent 885 9f6ad2286011
child 990 8e20c48a9c13
permissions -rw-r--r--
Date: Sat, 26 Jun 2004 14:58:42 +0300 From: "Mike Gorchak" Subject: QNX 6.3 fixes for SDL Sam, I've added new OpenGL framework for SDL, which appeared in the new QNX version - 6.3. I've leave compatibility with previous QNX versions. And I've moved all GL specific functions to the separate module, like it done for the other platforms. SDL is now ready for the QNX 6.3 :)

/*
 * 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"

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);
		exit(1);
	}
}

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];
#if defined(_WIN32)
	char *gl_library = "OpenGL32.DLL";
#elif defined(__QNXNTO__)
	char *gl_library = "libGL.so.3";
#else
	char *gl_library = "libGL.so.1";
#endif
	
	if (argv[1]) {
		gl_library = argv[1];
	}
	
	if (SDL_Init(SDL_INIT_VIDEO)<0)
	{
		printf("Unable to init SDL : %s\n",SDL_GetError());
		exit(1);
	}
	
	if (SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER,1)<0)
	{
		printf("Unable to set GL attribute : %s\n",SDL_GetError());
		exit(1);
	}
	
	if (SDL_GL_LoadLibrary(gl_library)<0)
	{
		printf("Unable to dynamically open GL lib : %s\n",SDL_GetError());
		exit(1);
	}

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