Mercurial > sdl-ios-xcode
annotate test/automated/platform/platform.h @ 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> |
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date | Sat, 03 Oct 2009 16:23:16 +0000 |
parents | 22ac66da0765 |
children | 0c429a5fda8a |
rev | line source |
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3259
22ac66da0765
Merged Edgar's code changes from Google Summer of Code 2009
Sam Lantinga <slouken@libsdl.org>
parents:
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1 /** |
22ac66da0765
Merged Edgar's code changes from Google Summer of Code 2009
Sam Lantinga <slouken@libsdl.org>
parents:
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2 * Part of SDL test suite. |
22ac66da0765
Merged Edgar's code changes from Google Summer of Code 2009
Sam Lantinga <slouken@libsdl.org>
parents:
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3 * |
22ac66da0765
Merged Edgar's code changes from Google Summer of Code 2009
Sam Lantinga <slouken@libsdl.org>
parents:
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4 * Written by Edgar Simo "bobbens" |
22ac66da0765
Merged Edgar's code changes from Google Summer of Code 2009
Sam Lantinga <slouken@libsdl.org>
parents:
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5 * |
22ac66da0765
Merged Edgar's code changes from Google Summer of Code 2009
Sam Lantinga <slouken@libsdl.org>
parents:
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6 * Released under Public Domain. |
22ac66da0765
Merged Edgar's code changes from Google Summer of Code 2009
Sam Lantinga <slouken@libsdl.org>
parents:
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7 */ |
22ac66da0765
Merged Edgar's code changes from Google Summer of Code 2009
Sam Lantinga <slouken@libsdl.org>
parents:
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8 |
22ac66da0765
Merged Edgar's code changes from Google Summer of Code 2009
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
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9 |
22ac66da0765
Merged Edgar's code changes from Google Summer of Code 2009
Sam Lantinga <slouken@libsdl.org>
parents:
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10 #ifndef _TEST_PLATFORM |
22ac66da0765
Merged Edgar's code changes from Google Summer of Code 2009
Sam Lantinga <slouken@libsdl.org>
parents:
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11 # define _TEST_PLATFORM |
22ac66da0765
Merged Edgar's code changes from Google Summer of Code 2009
Sam Lantinga <slouken@libsdl.org>
parents:
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12 |
22ac66da0765
Merged Edgar's code changes from Google Summer of Code 2009
Sam Lantinga <slouken@libsdl.org>
parents:
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13 |
22ac66da0765
Merged Edgar's code changes from Google Summer of Code 2009
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
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14 const char *platform_getPlatform (void); |
22ac66da0765
Merged Edgar's code changes from Google Summer of Code 2009
Sam Lantinga <slouken@libsdl.org>
parents:
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15 int test_platform (void); |
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Merged Edgar's code changes from Google Summer of Code 2009
Sam Lantinga <slouken@libsdl.org>
parents:
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16 |
22ac66da0765
Merged Edgar's code changes from Google Summer of Code 2009
Sam Lantinga <slouken@libsdl.org>
parents:
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changeset
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17 |
22ac66da0765
Merged Edgar's code changes from Google Summer of Code 2009
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
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18 #endif /* _TEST_PLATFORM */ |
22ac66da0765
Merged Edgar's code changes from Google Summer of Code 2009
Sam Lantinga <slouken@libsdl.org>
parents:
diff
changeset
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19 |