sdl2.pc.in
author Sam Lantinga <slouken@libsdl.org>
Wed, 30 Nov 2016 22:06:05 -0800
changeset 10668 1889c850fafc
parent 7876 d6373384b5ce
permissions -rw-r--r--
Fixed bug 3340 - SDL_BlitScaled causes access violation in some cases.

Simon Hug

The SDL_BlitScaled function runs into an access violation for specific blit coordinates and surface sizes. The attached testcase blits a 800x600 surface to a 1280x720 surface at the coordinates -640,-345 scaled to 1280x720. The blit function that moves the data then runs over and reads after the pixel data from the src surface causing an access violation.

I can't say where exactly it goes wrong, but I think it could have something to do with the rounding in SDL_UpperBlitScaled. final_src.y is 288 and final_src.h is 313. Together that's 601, which I believe is one too much, but I just don't know the code enough to make sure that's the problem.

Sylvain

I think this patch fix the issue, but maybe it's worth re-writing "SDL_UpperBlitScaled" using SDL_FRect.
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# sdl pkg-config source file
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prefix=@prefix@
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exec_prefix=@exec_prefix@
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libdir=@libdir@
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includedir=@includedir@
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Name: sdl2
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Description: Simple DirectMedia Layer is a cross-platform multimedia library designed to provide low level access to audio, keyboard, mouse, joystick, 3D hardware via OpenGL, and 2D video framebuffer.
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Version: @SDL_VERSION@
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Requires:
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Conflicts:
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Libs: -L${libdir} @SDL_RLD_FLAGS@ @SDL_LIBS@
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Libs.private: @SDL_STATIC_LIBS@
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Cflags: -I${includedir}/SDL2 @SDL_CFLAGS@