diff src/events/SDL_mouse.c @ 0:74212992fb08

Initial revision
author Sam Lantinga <slouken@lokigames.com>
date Thu, 26 Apr 2001 16:45:43 +0000
parents
children e8157fcb3114
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/events/SDL_mouse.c	Thu Apr 26 16:45:43 2001 +0000
@@ -0,0 +1,247 @@
+/*
+    SDL - Simple DirectMedia Layer
+    Copyright (C) 1997, 1998, 1999, 2000, 2001  Sam Lantinga
+
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Library General Public
+    License as published by the Free Software Foundation; either
+    version 2 of the License, or (at your option) any later version.
+
+    This library is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+    Library General Public License for more details.
+
+    You should have received a copy of the GNU Library General Public
+    License along with this library; if not, write to the Free
+    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+    Sam Lantinga
+    slouken@devolution.com
+*/
+
+#ifdef SAVE_RCSID
+static char rcsid =
+ "@(#) $Id$";
+#endif
+
+/* General mouse handling code for SDL */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "SDL_events.h"
+#include "SDL_events_c.h"
+#include "SDL_cursor_c.h"
+#include "SDL_sysvideo.h"
+
+
+/* These are static for our mouse handling code */
+static Sint16 SDL_MouseX = 0;
+static Sint16 SDL_MouseY = 0;
+static Sint16 SDL_DeltaX = 0;
+static Sint16 SDL_DeltaY = 0;
+static Uint8  SDL_ButtonState = 0;
+
+
+/* Public functions */
+int SDL_MouseInit(void)
+{
+	/* The mouse is at (0,0) */
+	SDL_MouseX = 0;
+	SDL_MouseY = 0;
+	SDL_DeltaX = 0;
+	SDL_DeltaY = 0;
+	SDL_ButtonState = 0;
+
+	/* That's it! */
+	return(0);
+}
+
+Uint8 SDL_GetMouseState (int *x, int *y)
+{
+	if ( x )
+		*x = SDL_MouseX;
+	if ( y )
+		*y = SDL_MouseY;
+	return(SDL_ButtonState);
+}
+
+Uint8 SDL_GetRelativeMouseState (int *x, int *y)
+{
+	if ( x )
+		*x = SDL_DeltaX;
+	if ( y )
+		*y = SDL_DeltaY;
+	SDL_DeltaX = 0;
+	SDL_DeltaY = 0;
+	return(SDL_ButtonState);
+}
+
+static void ClipOffset(Sint16 *x, Sint16 *y)
+{
+	/* This clips absolute mouse coordinates when the apparent
+	   display surface is smaller than the real display surface.
+	 */
+	if ( SDL_VideoSurface->offset ) {
+		*y -= SDL_VideoSurface->offset/SDL_VideoSurface->pitch;
+		*x -= (SDL_VideoSurface->offset%SDL_VideoSurface->pitch)/
+				SDL_VideoSurface->format->BytesPerPixel;
+	}
+}
+
+/* These are global for SDL_eventloop.c */
+int SDL_PrivateMouseMotion(Uint8 buttonstate, int relative, Sint16 x, Sint16 y)
+{
+	int posted;
+	Uint16 X, Y;
+	Sint16 Xrel;
+	Sint16 Yrel;
+
+	/* Don't handle mouse motion if there's no cursor surface */
+	if ( SDL_VideoSurface == NULL ) {
+		return(0);
+	}
+
+	/* Default buttonstate is the current one */
+	if ( ! buttonstate ) {
+		buttonstate = SDL_ButtonState;
+	}
+
+	Xrel = x;
+	Yrel = y;
+	if ( relative ) {
+		/* Push the cursor around */
+		x = (SDL_MouseX+x);
+		y = (SDL_MouseY+y);
+	} else {
+		/* Do we need to clip {x,y} ? */
+		ClipOffset(&x, &y);
+	}
+
+	/* Mouse coordinates range from 0 - width-1 and 0 - height-1 */
+	if ( x < 0 )
+		X = 0;
+	else
+	if ( x >= SDL_VideoSurface->w )
+		X = SDL_VideoSurface->w-1;
+	else
+		X = (Uint16)x;
+
+	if ( y < 0 )
+		Y = 0;
+	else
+	if ( y >= SDL_VideoSurface->h )
+		Y = SDL_VideoSurface->h-1;
+	else
+		Y = (Uint16)y;
+
+	/* If not relative mode, generate relative motion from clamped X/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 ) {
+		Xrel = X-SDL_MouseX;
+		Yrel = Y-SDL_MouseY;
+	}
+
+	/* Update internal mouse state */
+	SDL_ButtonState = buttonstate;
+	SDL_MouseX = X;
+	SDL_MouseY = Y;
+	SDL_DeltaX += Xrel;
+	SDL_DeltaY += Yrel;
+	SDL_MoveCursor(SDL_MouseX, SDL_MouseY);
+
+	/* Post the event, if desired */
+	posted = 0;
+	if ( SDL_ProcessEvents[SDL_MOUSEMOTION] == SDL_ENABLE ) {
+		SDL_Event event;
+		memset(&event, 0, sizeof(event));
+		event.type = SDL_MOUSEMOTION;
+		event.motion.state = buttonstate;
+		event.motion.x = X;
+		event.motion.y = Y;
+		event.motion.xrel = Xrel;
+		event.motion.yrel = Yrel;
+		if ( (SDL_EventOK == NULL) || (*SDL_EventOK)(&event) ) {
+			posted = 1;
+			SDL_PushEvent(&event);
+		}
+	}
+	return(posted);
+}
+
+int SDL_PrivateMouseButton(Uint8 state, Uint8 button, Sint16 x, Sint16 y)
+{
+	SDL_Event event;
+	int posted;
+	int move_mouse;
+	Uint8 buttonstate;
+
+	memset(&event, 0, sizeof(event));
+
+	/* Check parameters */
+	if ( x || y ) {
+		ClipOffset(&x, &y);
+		move_mouse = 1;
+		/* Mouse coordinates range from 0 - width-1 and 0 - height-1 */
+		if ( x < 0 )
+			x = 0;
+		else
+		if ( x >= SDL_VideoSurface->w )
+			x = SDL_VideoSurface->w-1;
+
+		if ( y < 0 )
+			y = 0;
+		else
+		if ( y >= SDL_VideoSurface->h )
+			y = SDL_VideoSurface->h-1;
+	} else {
+		move_mouse = 0;
+	}
+	if ( ! x )
+		x = SDL_MouseX;
+	if ( ! y )
+		y = SDL_MouseY;
+
+	/* Figure out which event to perform */
+	buttonstate = SDL_ButtonState;
+	switch ( state ) {
+		case SDL_PRESSED:
+			event.type = SDL_MOUSEBUTTONDOWN;
+			buttonstate |= SDL_BUTTON(button);
+			break;
+		case SDL_RELEASED:
+			event.type = SDL_MOUSEBUTTONUP;
+			buttonstate &= ~SDL_BUTTON(button);
+			break;
+		default:
+			/* Invalid state -- bail */
+			return(0);
+	}
+
+	/* Update internal mouse state */
+	SDL_ButtonState = buttonstate;
+	if ( move_mouse ) {
+		SDL_MouseX = x;
+		SDL_MouseY = y;
+		SDL_MoveCursor(SDL_MouseX, SDL_MouseY);
+	}
+
+	/* Post the event, if desired */
+	posted = 0;
+	if ( SDL_ProcessEvents[event.type] == SDL_ENABLE ) {
+		event.button.state = state;
+		event.button.button = button;
+		event.button.x = x;
+		event.button.y = y;
+		if ( (SDL_EventOK == NULL) || (*SDL_EventOK)(&event) ) {
+			posted = 1;
+			SDL_PushEvent(&event);
+		}
+	}
+	return(posted);
+}
+