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 */
33 static Sint16 SDL_MouseX = 0;
34 static Sint16 SDL_MouseY = 0;
35 static Sint16 SDL_DeltaX = 0;
36 static Sint16 SDL_DeltaY = 0;
37 static Sint16 SDL_MouseMaxX = 0;
38 static Sint16 SDL_MouseMaxY = 0;
39 static Uint8 SDL_ButtonState = 0;
40
41
42 /* Public functions */
SDL_MouseInit(void)43 int 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 }
SDL_MouseQuit(void)57 void SDL_MouseQuit(void)
58 {
59 }
60
61 /* We lost the mouse, so post button up messages for all pressed buttons */
SDL_ResetMouse(void)62 void 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
SDL_GetMouseState(int * x,int * y)72 Uint8 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
SDL_GetRelativeMouseState(int * x,int * y)83 Uint8 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
ClipOffset(Sint16 * x,Sint16 * y)94 static 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
SDL_SetMouseRange(int maxX,int maxY)106 void 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 */
SDL_PrivateMouseMotion(Uint8 buttonstate,int relative,Sint16 x,Sint16 y)113 int 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
165 printf("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
SDL_PrivateMouseButton(Uint8 state,Uint8 button,Sint16 x,Sint16 y)197 int 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