1/*
2    SDL - Simple DirectMedia Layer
3    Copyright (C) 1997-2012 Sam Lantinga
4
5    This library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Lesser General Public
7    License as published by the Free Software Foundation; either
8    version 2.1 of the License, or (at your option) any later version.
9
10    This library is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13    Lesser General Public License for more details.
14
15    You should have received a copy of the GNU Lesser General Public
16    License along with this library; if not, write to the Free Software
17    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
18
19    Sam Lantinga
20    slouken@libsdl.org
21*/
22#include "SDL_config.h"
23
24/* General mouse handling code for SDL */
25
26#include "SDL_events.h"
27#include "SDL_events_c.h"
28#include "../video/SDL_cursor_c.h"
29#include "../video/SDL_sysvideo.h"
30
31
32/* These are static for our mouse handling code */
33static Sint16 SDL_MouseX = 0;
34static Sint16 SDL_MouseY = 0;
35static Sint16 SDL_DeltaX = 0;
36static Sint16 SDL_DeltaY = 0;
37static Sint16 SDL_MouseMaxX = 0;
38static Sint16 SDL_MouseMaxY = 0;
39static Uint8  SDL_ButtonState = 0;
40
41
42/* Public functions */
43int SDL_MouseInit(void)
44{
45	/* The mouse is at (0,0) */
46	SDL_MouseX = 0;
47	SDL_MouseY = 0;
48	SDL_DeltaX = 0;
49	SDL_DeltaY = 0;
50	SDL_MouseMaxX = 0;
51	SDL_MouseMaxY = 0;
52	SDL_ButtonState = 0;
53
54	/* That's it! */
55	return(0);
56}
57void SDL_MouseQuit(void)
58{
59}
60
61/* We lost the mouse, so post button up messages for all pressed buttons */
62void SDL_ResetMouse(void)
63{
64	Uint8 i;
65	for ( i = 0; i < sizeof(SDL_ButtonState)*8; ++i ) {
66		if ( SDL_ButtonState & SDL_BUTTON(i) ) {
67			SDL_PrivateMouseButton(SDL_RELEASED, i, 0, 0);
68		}
69	}
70}
71
72Uint8 SDL_GetMouseState (int *x, int *y)
73{
74	if ( x ) {
75		*x = SDL_MouseX;
76	}
77	if ( y ) {
78		*y = SDL_MouseY;
79	}
80	return(SDL_ButtonState);
81}
82
83Uint8 SDL_GetRelativeMouseState (int *x, int *y)
84{
85	if ( x )
86		*x = SDL_DeltaX;
87	if ( y )
88		*y = SDL_DeltaY;
89	SDL_DeltaX = 0;
90	SDL_DeltaY = 0;
91	return(SDL_ButtonState);
92}
93
94static void ClipOffset(Sint16 *x, Sint16 *y)
95{
96	/* This clips absolute mouse coordinates when the apparent
97	   display surface is smaller than the real display surface.
98	 */
99	if ( SDL_VideoSurface && SDL_VideoSurface->offset ) {
100		*y -= SDL_VideoSurface->offset/SDL_VideoSurface->pitch;
101		*x -= (SDL_VideoSurface->offset%SDL_VideoSurface->pitch)/
102				SDL_VideoSurface->format->BytesPerPixel;
103	}
104}
105
106void SDL_SetMouseRange(int maxX, int maxY)
107{
108	SDL_MouseMaxX = (Sint16)maxX;
109	SDL_MouseMaxY = (Sint16)maxY;
110}
111
112/* These are global for SDL_eventloop.c */
113int SDL_PrivateMouseMotion(Uint8 buttonstate, int relative, Sint16 x, Sint16 y)
114{
115	int posted;
116	Uint16 X, Y;
117	Sint16 Xrel;
118	Sint16 Yrel;
119
120	/* Default buttonstate is the current one */
121	if ( ! buttonstate ) {
122		buttonstate = SDL_ButtonState;
123	}
124
125	Xrel = x;
126	Yrel = y;
127	if ( relative ) {
128		/* Push the cursor around */
129		x = (SDL_MouseX+x);
130		y = (SDL_MouseY+y);
131	} else {
132		/* Do we need to clip {x,y} ? */
133		ClipOffset(&x, &y);
134	}
135
136	/* Mouse coordinates range from 0 - width-1 and 0 - height-1 */
137	if ( x < 0 )
138		X = 0;
139	else
140	if ( x >= SDL_MouseMaxX )
141		X = SDL_MouseMaxX-1;
142	else
143		X = (Uint16)x;
144
145	if ( y < 0 )
146		Y = 0;
147	else
148	if ( y >= SDL_MouseMaxY )
149		Y = SDL_MouseMaxY-1;
150	else
151		Y = (Uint16)y;
152
153	/* If not relative mode, generate relative motion from clamped X/Y.
154	   This prevents lots of extraneous large delta relative motion when
155	   the screen is windowed mode and the mouse is outside the window.
156	*/
157	if ( ! relative ) {
158		Xrel = X-SDL_MouseX;
159		Yrel = Y-SDL_MouseY;
160	}
161
162	/* Drop events that don't change state */
163	if ( ! Xrel && ! Yrel ) {
164#if 0
165printf("Mouse event didn't change state - dropped!\n");
166#endif
167		return(0);
168	}
169
170	/* Update internal mouse state */
171	SDL_ButtonState = buttonstate;
172	SDL_MouseX = X;
173	SDL_MouseY = Y;
174	SDL_DeltaX += Xrel;
175	SDL_DeltaY += Yrel;
176        SDL_MoveCursor(SDL_MouseX, SDL_MouseY);
177
178	/* Post the event, if desired */
179	posted = 0;
180	if ( SDL_ProcessEvents[SDL_MOUSEMOTION] == SDL_ENABLE ) {
181		SDL_Event event;
182		SDL_memset(&event, 0, sizeof(event));
183		event.type = SDL_MOUSEMOTION;
184		event.motion.state = buttonstate;
185		event.motion.x = X;
186		event.motion.y = Y;
187		event.motion.xrel = Xrel;
188		event.motion.yrel = Yrel;
189		if ( (SDL_EventOK == NULL) || (*SDL_EventOK)(&event) ) {
190			posted = 1;
191			SDL_PushEvent(&event);
192		}
193	}
194	return(posted);
195}
196
197int SDL_PrivateMouseButton(Uint8 state, Uint8 button, Sint16 x, Sint16 y)
198{
199	SDL_Event event;
200	int posted;
201	int move_mouse;
202	Uint8 buttonstate;
203
204	SDL_memset(&event, 0, sizeof(event));
205
206	/* Check parameters */
207	if ( x || y ) {
208		ClipOffset(&x, &y);
209		move_mouse = 1;
210		/* Mouse coordinates range from 0 - width-1 and 0 - height-1 */
211		if ( x < 0 )
212			x = 0;
213		else
214		if ( x >= SDL_MouseMaxX )
215			x = SDL_MouseMaxX-1;
216
217		if ( y < 0 )
218			y = 0;
219		else
220		if ( y >= SDL_MouseMaxY )
221			y = SDL_MouseMaxY-1;
222	} else {
223		move_mouse = 0;
224	}
225	if ( ! x )
226		x = SDL_MouseX;
227	if ( ! y )
228		y = SDL_MouseY;
229
230	/* Figure out which event to perform */
231	buttonstate = SDL_ButtonState;
232	switch ( state ) {
233		case SDL_PRESSED:
234			event.type = SDL_MOUSEBUTTONDOWN;
235			buttonstate |= SDL_BUTTON(button);
236			break;
237		case SDL_RELEASED:
238			event.type = SDL_MOUSEBUTTONUP;
239			buttonstate &= ~SDL_BUTTON(button);
240			break;
241		default:
242			/* Invalid state -- bail */
243			return(0);
244	}
245
246	/* Update internal mouse state */
247	SDL_ButtonState = buttonstate;
248	if ( move_mouse ) {
249		SDL_MouseX = x;
250		SDL_MouseY = y;
251		SDL_MoveCursor(SDL_MouseX, SDL_MouseY);
252	}
253
254	/* Post the event, if desired */
255	posted = 0;
256	if ( SDL_ProcessEvents[event.type] == SDL_ENABLE ) {
257		event.button.state = state;
258		event.button.button = button;
259		event.button.x = x;
260		event.button.y = y;
261		if ( (SDL_EventOK == NULL) || (*SDL_EventOK)(&event) ) {
262			posted = 1;
263			SDL_PushEvent(&event);
264		}
265	}
266	return(posted);
267}
268
269