framebuffer

Using a couple of posts here in StackOverflow, I created what is supposed to be a simple render-to-texture using a framebuffer. The problem here is that it's not working. Something is broken in the mix, as my final texture is just a white square. I am not getting any gl errors whatsoever. Here is my code. Declare instance variables. GLuint texture; GLuint textureFrameBuffer; Generate the texture and framebuffer. glGetError(); //Generate the texture that we will draw to (saves us a lot of processor). glEnable(GL_TEXTURE_2D); glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); //

I am running the boiler plate OpenGL example code that XCode creates for an OpenGL project for iOS. This sets up a simple ViewController and uses GLKit to handle the rest of the work. All the update/draw functionality of the application is in C++. It is cross platform. There is a lot of framebuffer creation going on. The draw phase renders to a few frame buffers and then tries to set it back to the default framebuffer. glBindFramebuffer(GL_FRAMEBUFFER, 0); This generates an GL_INVALID_ENUM. Only on iOS. I am completely stumped as to why. The code runs fine on all major platforms except iOS. I

Gralloc模块是从Android Eclair（android 2.1）开始加入的一个HAL模块，Gralloc的含义为是Graphics Alloc(图形分配)。他对上为libui提供服务，为其分配显存，刷新显示等。对下对framebuffer进行管理。 gralloc代码通常位于hardware/libhardware/modules/gralloc目录下。包含以下几个文件： Android.mk framebuffer.cpp gralloc.cpp gralloc_priv.h gr.h mapper.cpp 另外，与其相关的头文件位于hardware/libhardware/include/hardware，涉及fb.h和gralloc.h。 下面从gralloc的调用开始学习gralloc的代码。代码基于android4.4。 gralloc的调用是从FramebufferNativeWindow.cpp的构造函数开始的。FramebufferNativeWindow实现FrameBuffer的管理，它主要被SurfaceFlinger使用，也可以被OpenGL Native程序使用。在本质上，它在Framebuffer之上实现了一个ANativeWindow，目前它只管理两个buffers:front and back buffer。 如下所示

I am trying to figure out a way to cut out a certain region of a background texture such that a certain custom pattern is not rendered on the screen for that background. For example: This square can be any pattern. I am using Frame Buffer Object and Stencil Buffer to achieve this kind of effect. Here is the code: fbo.begin(); //Disables ColorMask and DepthMask so that all the rendering is done on the Stencil Buffer Gdx.gl20.glColorMask(false, false, false, false); Gdx.gl20.glDepthMask(false); Gdx.gl20.glEnable(GL20.GL_STENCIL_TEST); Gdx.gl20.glStencilFunc(GL20.GL_ALWAYS, 1, 0xFFFFFFFF); Gdx

I'm quite a bit confused about framebuffers. What I want to do is using a framebuffer with multiple textures attached, fill every texture and then use a shader to combine (blend) all textures to create a new output. Sounds easy? yeah that's what I thought too, but I don't understand it. How can I pass the currently binded texture to a shader? What you need is to put the texture in a specific slot, then use a sampler to read from it. In your app: GLuint frameBuffer; glGenFramebuffersEXT(1, &frameBuffer); //Create a frame buffer glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, frameBuffer); //Bind it so

I'm trying to read pixels out of the screen buffer, I'm creating a CGImageRef with CGDisplayCreateImage , but the values for CGImageGetWidth and CGImageGetBytesPerRow Don't make sense together, dividing the bytes per row by the bytes per pixel gives me 1376 pixels per row, but the width of the image is 1366. What's going on here? Is there some kind of padding in the image? How do I read from the data I'm getting out of it safely, and with the correct results? Edit: The minimal code needed to reproduce this is the following: #import <Foundation/Foundation.h> #import <ApplicationServices

off-screen rendering to a texture-bound offscreen framebuffer object should be so trivial but I'm having a problem I cannot wrap my head around. My full sample program (2D only for now!) is here: http://pastebin.com/hSvXzhJT See below for some descriptions. I'm creating an rgba texture object 512x512, bind it to an FBO. No depth or other render buffers are needed at this point, strictly 2D. The following extremely simple shaders render to this texture: Vertex shader: varying vec2 vPos; attribute vec2 aPos; void main (void) { vPos = (aPos + 1) / 2; gl_Position = vec4(aPos, 0.0, 1.0); } In aPos