Date: Sun, 18 Jul 2004 00:22:07 -0400

From: "Philippe Anctil"
Subject: [SDL] odd mouse event generated on init

The mouse relative and absolute coordinates appear to be always equal for
the first mouse event.

--HG--
extra : convert_revision : svn%3Ac70aab31-4412-0410-b14c-859654838e24/trunk%40944

src/events/SDL_mouse.c

@@ -38,8 +38,8 @@ static char rcsid =
 
 
 /* These are static for our mouse handling code */
-static Sint16 SDL_MouseX = 0;
-static Sint16 SDL_MouseY = 0;
+static Sint16 SDL_MouseX = -1;
+static Sint16 SDL_MouseY = -1;
 static Sint16 SDL_DeltaX = 0;
 static Sint16 SDL_DeltaY = 0;
 static Uint8  SDL_ButtonState = 0;
@@ -49,8 +49,8 @@ static Uint8  SDL_ButtonState = 0;
 int SDL_MouseInit(void)
 {
 	/* The mouse is at (0,0) */
-	SDL_MouseX = 0;
-	SDL_MouseY = 0;
+	SDL_MouseX = -1;
+	SDL_MouseY = -1;
 	SDL_DeltaX = 0;
 	SDL_DeltaY = 0;
 	SDL_ButtonState = 0;
@@ -72,10 +72,20 @@ void SDL_ResetMouse(void)
 
 Uint8 SDL_GetMouseState (int *x, int *y)
 {
-	if ( x )
+	if ( x ) {
+		if ( SDL_MouseX < 0 ) {
+			*x = 0;
+		} else {
 			*x = SDL_MouseX;
-	if ( y )
+		}
+	}
+	if ( y ) {
+		if ( SDL_MouseY < 0 ) {
+			*y = 0;
+		} else {
 			*y = SDL_MouseY;
+		}
+	}
 	return(SDL_ButtonState);
 }
 
@@ -152,7 +162,7 @@ int SDL_PrivateMouseMotion(Uint8 buttonstate, int relative, Sint16 x, Sint16 y)
 	   This prevents lots of extraneous large delta relative motion when
 	   the screen is windowed mode and the mouse is outside the window.
 	*/
-	if ( ! relative ) {
+	if ( ! relative && SDL_MouseX >= 0 && SDL_MouseY >= 0 ) {
 		Xrel = X-SDL_MouseX;
 		Yrel = Y-SDL_MouseY;
 	}