Mercurial > sdl-ios-xcode
view include/SDL_blendmode.h @ 5053:b5b42be9333c
Fixed bug #1026
Vittorio Giovara 2010-07-16 19:09:28 PDT
i was reading SDL_renderer_gles and i noticed that every time we there
is some gl call the gl state is modified with a couple of
glEnableClientState()/glDisableClientState.
While this is completely fine for desktops systems, this is a major
performace kill on mobile devices, right where opengles is
implemented.
Normal practice in this case is to update the glstate once, keep it
always the same and disable/enable other states only in very special
occasions.
On the web there's plenty of documentation (on the top of my head
http://developer.apple.com/iphone/library/documentation/3DDrawing/Conceptual/OpenGLES_ProgrammingGuide/Performance/Performance.html#//apple_ref/doc/uid/TP40008793-CH105-SW5
) and i personally tried this.
I modified my code and got a 10 fps boost, then modified SDL_render_gles and
shifted from 40 fps to 50 fps alone -- considering that i started from ~30fps i
got an 80% performance increase with this technique.
I have attached a dif of my changes, hope that it will be included in
mainstream.
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Wed, 19 Jan 2011 23:56:16 -0800 |
parents | aa8888658021 |
children | e743b9c3f6d6 |
line wrap: on
line source
/* SDL - Simple DirectMedia Layer Copyright (C) 1997-2010 Sam Lantinga This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA Sam Lantinga slouken@libsdl.org */ /** * \file SDL_blendmode.h * * Header file declaring the SDL_BlendMode enumeration */ #ifndef _SDL_blendmode_h #define _SDL_blendmode_h #include "begin_code.h" /* Set up for C function definitions, even when using C++ */ #ifdef __cplusplus /* *INDENT-OFF* */ extern "C" { /* *INDENT-ON* */ #endif /** * \brief The blend mode used in SDL_RenderCopy() and drawing operations. */ typedef enum { SDL_BLENDMODE_NONE = 0x00000000, /**< No blending */ SDL_BLENDMODE_MASK = 0x00000001, /**< dst = A ? src : dst (alpha is mask) */ SDL_BLENDMODE_BLEND = 0x00000002, /**< dst = (src * A) + (dst * (1-A)) */ SDL_BLENDMODE_ADD = 0x00000004, /**< dst = (src * A) + dst */ SDL_BLENDMODE_MOD = 0x00000008 /**< dst = src * dst */ } SDL_BlendMode; /* Ends C function definitions when using C++ */ #ifdef __cplusplus /* *INDENT-OFF* */ } /* *INDENT-ON* */ #endif #include "close_code.h" #endif /* _SDL_video_h */ /* vi: set ts=4 sw=4 expandtab: */