Mercurial > sdl-ios-xcode
view src/video/Xext/XmuStdCmap/DelCmap.c @ 3333:b334b4f7dfa0
[SDL] Bad math in SDL_RenderCopy
Mason Wheeler to sdl
When I tried to render an image using something other than NULL for srcrect, it got horribly distorted. I traced it down to the fact that the math in the rectangle adjustments performed just before the call to renderer->RenderCopy is written inside out. It should look like this:
if (dstrect->w != real_dstrect.w) {
int deltax = (dstrect->x - real_dstrect.x);
int deltaw = (dstrect->w - real_dstrect.w);
real_srcrect.x += (deltax * real_srcrect.w) / dstrect->w;
real_srcrect.w += (deltaw * real_srcrect.w) / dstrect->w;
}
if (dstrect->h != real_dstrect.h) {
int deltay = (dstrect->y - real_dstrect.y);
int deltah = (dstrect->h - real_dstrect.h);
real_srcrect.y += (deltay * real_srcrect.h) / dstrect->h;
real_srcrect.h += (deltah * real_srcrect.h) / dstrect->h;
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Sat, 03 Oct 2009 16:23:16 +0000 |
parents | 2032348afed1 |
children |
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/* $Xorg: DelCmap.c,v 1.4 2001/02/09 02:03:52 xorgcvs Exp $ */ /* Copyright 1989, 1998 The Open Group Permission to use, copy, modify, distribute, and sell this software and its documentation for any purpose is hereby granted without fee, provided that the above copyright notice appear in all copies and that both that copyright notice and this permission notice appear in supporting documentation. The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. Except as contained in this notice, the name of The Open Group shall not be used in advertising or otherwise to promote the sale, use or other dealings in this Software without prior written authorization from The Open Group. */ /* $XFree86: xc/lib/Xmu/DelCmap.c,v 1.6 2001/01/17 19:42:54 dawes Exp $ */ /* * Author: Donna Converse, MIT X Consortium */ #ifdef HAVE_CONFIG_H #include <config.h> #endif #include <X11/Xlib.h> #include <X11/Xutil.h> #include "../extensions/StdCmap.h" /* To remove any standard colormap property, use XmuDeleteStandardColormap(). * XmuDeleteStandardColormap() will remove the specified property from the * specified screen, releasing any resources used by the colormap(s) of the * property if possible. */ void XmuDeleteStandardColormap(Display * dpy, int screen, Atom property) /* dpy; - specifies the X server to connect to * screen - specifies the screen of the display * property - specifies the standard colormap property */ { XStandardColormap *stdcmaps, *s; int count = 0; if (XGetRGBColormaps(dpy, RootWindow(dpy, screen), &stdcmaps, &count, property)) { for (s = stdcmaps; count > 0; count--, s++) { if ((s->killid == ReleaseByFreeingColormap) && (s->colormap != None) && (s->colormap != DefaultColormap(dpy, screen))) XFreeColormap(dpy, s->colormap); else if (s->killid != None) XKillClient(dpy, s->killid); } XDeleteProperty(dpy, RootWindow(dpy, screen), property); XFree((char *) stdcmaps); XSync(dpy, False); } }