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comparison src/scrollbar-msw.c @ 412:697ef44129c6 r21-2-14

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Import from CVS: tag r21-2-14
author cvs
date Mon, 13 Aug 2007 11:20:41 +0200
parents de805c49cfc1
children 11054d720c21
comparison
equal deleted inserted replaced
411:12e008d41344 412:697ef44129c6
263 vertical_drag_in_progress = 0; 263 vertical_drag_in_progress = 0;
264 break; 264 break;
265 } 265 }
266 } 266 }
267 267
268 static int
269 can_scroll(struct scrollbar_instance* scrollbar)
270 {
271 return scrollbar != NULL
272 && IsWindowVisible (SCROLLBAR_MSW_HANDLE (scrollbar))
273 && IsWindowEnabled (SCROLLBAR_MSW_HANDLE (scrollbar));
274 }
275
276 int
277 mswindows_handle_mousewheel_event (Lisp_Object frame, int keys, int delta)
278 {
279 int hasVertBar, hasHorzBar; /* Indicates prescence of scroll bars */
280 unsigned wheelScrollLines = 0; /* Number of lines per wheel notch */
281
282 /* Find the currently selected window */
283 Lisp_Object win = FRAME_SELECTED_WINDOW (XFRAME (frame));
284 struct window* w = XWINDOW (win);
285 struct window_mirror* mirror = find_window_mirror (w);
286
287 /* Check that there is something to scroll */
288 hasVertBar = can_scroll (mirror->scrollbar_vertical_instance);
289 hasHorzBar = can_scroll (mirror->scrollbar_horizontal_instance);
290 if (!hasVertBar && !hasHorzBar)
291 return FALSE;
292
293 /* No support for panning and zooming, so ignore */
294 if (keys & (MK_SHIFT | MK_CONTROL))
295 return FALSE;
296
297 /* Get the number of lines per wheel delta */
298 SystemParametersInfo (SPI_GETWHEELSCROLLLINES, 0, &wheelScrollLines, 0);
299
300 /* Calculate the amount to scroll */
301 if (wheelScrollLines == WHEEL_PAGESCROLL)
302 {
303 /* Scroll by a page */
304 Lisp_Object function;
305 if (hasVertBar)
306 function = delta > 0 ? Qscrollbar_page_up : Qscrollbar_page_down;
307 else
308 function = delta > 0 ? Qscrollbar_page_left : Qscrollbar_page_right;
309 mswindows_enqueue_misc_user_event (frame, function, Fcons (win, Qnil));
310 }
311 else /* Scroll by a number of lines */
312 {
313 /* Calc the number of lines to scroll */
314 int toScroll = MulDiv (delta, wheelScrollLines, WHEEL_DELTA);
315
316 /* Do the scroll */
317 Lisp_Object function;
318 if (hasVertBar)
319 function = delta > 0 ? Qscrollbar_line_up : Qscrollbar_line_down;
320 else
321 function = delta > 0 ? Qscrollbar_char_left : Qscrollbar_char_right;
322 if (toScroll < 0)
323 toScroll = -toScroll;
324 while (toScroll--)
325 mswindows_enqueue_misc_user_event (frame, function, win);
326 }
327
328 return TRUE;
329 }
330
331 #ifdef MEMORY_USAGE_STATS 268 #ifdef MEMORY_USAGE_STATS
332 269
333 static int 270 static int
334 mswindows_compute_scrollbar_instance_usage (struct device *d, 271 mswindows_compute_scrollbar_instance_usage (struct device *d,
335 struct scrollbar_instance *inst, 272 struct scrollbar_instance *inst,