Mercurial > sdl-ios-xcode
view src/video/bwindow/SDL_BView.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 | f7b03b6838cb |
children | b530ef003506 |
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/* 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 */ #include "SDL_config.h" #ifndef _SDL_BView_h #define _SDL_BView_h /* This is the event handling and graphics update portion of SDL_BWin */ extern "C" { #include "../../events/SDL_events_c.h" }; class SDL_BView:public BView { public: SDL_BView(BRect frame):BView(frame, "SDL View", B_FOLLOW_ALL_SIDES, (B_WILL_DRAW | B_FRAME_EVENTS)) { image = NULL; xoff = yoff = 0; SetViewColor(0, 0, 0, 0); SetHighColor(0, 0, 0, 0); } virtual ~ SDL_BView() { SetBitmap(NULL); } /* Set drawing offsets for fullscreen mode */ virtual void SetXYOffset(int x, int y) { xoff = x; yoff = y; } virtual void GetXYOffset(int &x, int &y) { x = xoff; y = yoff; } /* The view changed size. If it means we're in fullscreen, we * draw a nice black box in the entire view to get black borders. */ virtual void FrameResized(float width, float height) { BRect bounds; bounds.top = bounds.left = 0; bounds.right = width; bounds.bottom = height; /* Fill the entire view with black */ FillRect(bounds, B_SOLID_HIGH); /* And if there's an image, redraw it. */ if (image) { bounds = image->Bounds(); Draw(bounds); } } /* Drawing portion of this complete breakfast. :) */ virtual void SetBitmap(BBitmap * bitmap) { if (image) { delete image; } image = bitmap; } virtual void Draw(BRect updateRect) { if (image) { if (xoff || yoff) { BRect dest; dest.top = updateRect.top + yoff; dest.left = updateRect.left + xoff; dest.bottom = updateRect.bottom + yoff; dest.right = updateRect.right + xoff; DrawBitmap(image, updateRect, dest); } else { DrawBitmap(image, updateRect, updateRect); } } } virtual void DrawAsync(BRect updateRect) { if (xoff || yoff) { BRect dest; dest.top = updateRect.top + yoff; dest.left = updateRect.left + xoff; dest.bottom = updateRect.bottom + yoff; dest.right = updateRect.right + xoff;; DrawBitmapAsync(image, updateRect, dest); } else { DrawBitmapAsync(image, updateRect, updateRect); } } private: BBitmap * image; int xoff, yoff; }; #endif /* _SDL_BView_h */ /* vi: set ts=4 sw=4 expandtab: */