2014/10/15 下午 10:13:04

iphone Programming Glossary: quad

Hardware accelerated h.264 decoding to texture, overlay or similar in iOS

http://stackoverflow.com/questions/10646657/hardware-accelerated-h-264-decoding-to-texture-overlay-or-similar-in-ios

Android I am picturing something like rendering the video to a texture and using that texture to draw a full screen quad then use other sprites to draw the rest of the objects or maybe writing an intermediate filter just before the renderer..

Draw Graph curves with UIBezierPath

http://stackoverflow.com/questions/13719143/draw-graph-curves-with-uibezierpath

you can use the mid points as the end points of the sections of the curve and the points as the control points for a quad curve... So... Move to point m1. Add quad curve to point m2 with p2 as a control point. Add quad curve to point m3 with.. of the sections of the curve and the points as the control points for a quad curve... So... Move to point m1. Add quad curve to point m2 with p2 as a control point. Add quad curve to point m3 with p3 as a control point. Add quad curve to point.. control points for a quad curve... So... Move to point m1. Add quad curve to point m2 with p2 as a control point. Add quad curve to point m3 with p3 as a control point. Add quad curve to point m4 with p4 as a control point. and so on... This will..

Applying brightness and contrast with OpenGL ES

http://stackoverflow.com/questions/1506299/applying-brightness-and-contrast-with-opengl-es

the code for contrast in the sample from apple glActiveTexture GL_TEXTURE0 glVertexPointer 2 GL_FLOAT sizeof V2fT2f quad 0 .x glTexCoordPointer 2 GL_FLOAT sizeof V2fT2f quad 0 .s glTexEnvi GL_TEXTURE_ENV GL_TEXTURE_ENV_MODE GL_COMBINE glTexEnvi.. GL_TEXTURE0 glVertexPointer 2 GL_FLOAT sizeof V2fT2f quad 0 .x glTexCoordPointer 2 GL_FLOAT sizeof V2fT2f quad 0 .s glTexEnvi GL_TEXTURE_ENV GL_TEXTURE_ENV_MODE GL_COMBINE glTexEnvi GL_TEXTURE_ENV GL_COMBINE_RGB GL_MODULATE glTexEnvi..

Draw to offscreen renderbuffer in OpenGL ES (iPhone)

http://stackoverflow.com/questions/1853551/draw-to-offscreen-renderbuffer-in-opengl-es-iphone

good idea.. what you need to do is what @prideout said.. create a texture and render to it.. and use the texture on a quad every time. Make sure you draw to the texture only once as in your case things are persistent. void setUpTextureBuffer glGenFramebuffersOES..

How do I create blurred text in an iPhone view?

http://stackoverflow.com/questions/227305/how-do-i-create-blurred-text-in-an-iphone-view

iPhone sample. It does some blurring among other things. The relevant code includes static void blur V2fT2f quad float t t 1 GLint tex V2fT2f tmpquad 4 float offw t Input.wide float offh t Input.high int i glGetIntegerv GL_TEXTURE_BINDING_2D.. blurring among other things. The relevant code includes static void blur V2fT2f quad float t t 1 GLint tex V2fT2f tmpquad 4 float offw t Input.wide float offh t Input.high int i glGetIntegerv GL_TEXTURE_BINDING_2D tex Three pass small blur using.. samples filter across texel corners . .. . Pass one center nearest sample glVertexPointer 2 GL_FLOAT sizeof V2fT2f quad 0 .x glTexCoordPointer 2 GL_FLOAT sizeof V2fT2f quad 0 .s glTexEnvi GL_TEXTURE_ENV GL_TEXTURE_ENV_MODE GL_MODULATE glColor4f..

Finding the closest point to a given point

http://stackoverflow.com/questions/913576/finding-the-closest-point-to-a-given-point

If you need better than O N you can only get that if you first pay N lg N for building a spatial hash of some sort a quadtree octree hash grid or similar . Then each test will be approximately O lg N and can be much better typically by caching.. geocentric XYZ space because that allows me to get true distance not warped lat lon distance. However in practice a quad tree in lat lon space will probably work well enough. Once you have a hit you hold on to that tree node assuming the tree..