(Said Max Horn on the SDL mailing list...) Hi folks, based on Eric Wing's patch, I created the attached patch which fixes the OpenGL coordinate inversion bug in SDL. It works fine over here on 10.3 with Ryan's test program (which I also attached). There is another change in it: I removed the "- 1" in the two lines using CGDisplayPixelsHigh()... while I understand from a logical point of view why they *should* be correct, I checked the actual values computed that way, and they were off-by-one. After removing the " - 1", the returned mouse coordinates are correct. I checked this by moving the mouse to the screen top/bottom in fullscreen mode, BTW. With the change, the proper values 0 and 479 are returned (in 640x480 mode). Sam, you may still want to test on 10.1, it's very simple using Ryan's minimal test code :-) Cheers, Max (Here is the reproduction case for revision history's sake...) /* * To compile: * gcc -o test test.c `sdl-config --cflags` `sdl-config --libs` -framework OpenGL * * --ryan. */ #include <stdio.h> #include "SDL.h" #include "SDL_opengl.h" int main(int argc, char **argv) { Uint32 flags = SDL_OPENGL /* | SDL_FULLSCREEN */; SDL_Surface *screen; SDL_Event event; int done = 0; GLfloat ratio; SDL_Init(SDL_INIT_VIDEO); SDL_ShowCursor(0); if ((argv[1]) && (strcmp(argv[1], "--grab") == 0)) SDL_WM_GrabInput(SDL_GRAB_ON); screen = SDL_SetVideoMode(640, 480, 0, flags); if (!screen) return(42); ratio = ((GLfloat) screen->w) / ((GLfloat) screen->h); glClearColor( 0.0f, 0.0f, 0.0f, 0.0f ); glClearDepth( 1.0f ); glEnable( GL_DEPTH_TEST ); glDepthFunc( GL_LEQUAL ); glViewport( 0, 0, screen->w, screen->h); glMatrixMode( GL_PROJECTION ); glLoadIdentity(); gluPerspective( 45.0f, ratio, 0.1f, 100.0f ); glMatrixMode( GL_MODELVIEW ); glLoadIdentity(); glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); SDL_GL_SwapBuffers(); // eh, close enough. #define MAX_X 6.12 #define MAX_Y 4.50 while (!done) { int x, y; GLfloat glx, gly; if (!SDL_WaitEvent(&event)) break; switch (event.type) { case SDL_KEYUP: if (event.key.keysym.sym == SDLK_ESCAPE) done = 1; break; } SDL_GetMouseState(&x, &y); glx = ((((GLfloat) x) / ((GLfloat) screen->w)) - 0.5f) * MAX_X; gly = ((((GLfloat) y) / ((GLfloat) screen->h)) - 0.5f) * MAX_Y; glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glLoadIdentity(); glTranslatef(glx,-gly,-6.0f); glBegin(GL_TRIANGLES); glColor3f(1,0,0); glVertex3f( 0.00f, 0.25f, 0.00f); glColor3f(0,1,0); glVertex3f(-0.25f, -0.25f, 0.00f); glColor3f(0,0,1); glVertex3f( 0.25f, -0.25f, 0.00f); glEnd(); SDL_GL_SwapBuffers(); } SDL_Quit(); return(0); } /* end of test.c ... */

/* Simple test of the SDL threading code */

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

#include "SDL.h"
#include "SDL_thread.h"

#define NUMTHREADS 10

static char volatile time_for_threads_to_die[NUMTHREADS];

int SubThreadFunc(void *data) {
	while(! *(int volatile *)data) {
		; /*SDL_Delay(10); /* do nothing */
	}
	return 0;
}

int ThreadFunc(void *data) {
	SDL_Thread *sub_threads[NUMTHREADS];
	int flags[NUMTHREADS];
	int i;
	int tid = (int ) data;

	fprintf(stderr, "Creating Thread %d\n", tid);

	for(i = 0; i < NUMTHREADS; i++) {
		flags[i] = 0;
		sub_threads[i] = SDL_CreateThread(SubThreadFunc, &flags[i]);
	}

	printf("Thread '%d' waiting for signal\n", tid);
	while(time_for_threads_to_die[tid] != 1) {
		; /* do nothing */
	}

	printf("Thread '%d' sending signals to subthreads\n", tid);
	for(i = 0; i <  NUMTHREADS; i++) {
		flags[i] = 1;
		SDL_WaitThread(sub_threads[i], NULL);
	}

	printf("Thread '%d' exiting!\n", tid);

	return 0;
}

int main(int argc, char *argv[])
{
	SDL_Thread *threads[NUMTHREADS];
	int i;

	/* Load the SDL library */
	if ( SDL_Init(0) < 0 ) {
		fprintf(stderr, "Couldn't initialize SDL: %s\n",SDL_GetError());
		exit(1);
	}
	atexit(SDL_Quit);


	signal(SIGSEGV, SIG_DFL);
	for(i = 0; i < NUMTHREADS; i++) {
		time_for_threads_to_die[i] = 0;
		threads[i] = SDL_CreateThread(ThreadFunc, (void *) i);
	
		if ( threads[i] == NULL ) {
			fprintf(stderr,
			"Couldn't create thread: %s\n", SDL_GetError());
			exit(1);
		}
	}

	for(i = 0; i < NUMTHREADS; i++) {
		time_for_threads_to_die[i] = 1;
	}

	for(i = NUMTHREADS-1; i >= 0; --i) {
		SDL_WaitThread(threads[i], NULL);
	}
	return(0);	/* Never reached */
}