All Questions
Tagged with framebuffer opengl-es
147
questions
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108
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GL_INVALID_OPERAION in glDrawElements while rendering to Framebuffer from external texture
I am trying to render the contents of an external texture (which gets its data from android MediaCodec) to a framebuffer with a texture atttachment (first pass) and then using that texture to render ...
- 462
1
vote
1
answer
224
views
Delayed Pixel Buffer Read from Multiple Framebuffers on GL_TEXTURE_2D_ARRAY
Using Android, OpenGL ES 3.0
Attempting to write multiple layers of a GL_TEXTURE_2D_ARRAY using framebuffer objects to create heightmaps in sequence, and then read from all of the layers of the ...
- 1,322
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1
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236
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OpenGLES 3.0 Cannot render to a texture larger than the screen size
I have made an image below to indicate my problem. I render my scene to an offscreen framebuffer with a texture the size of the screen. I then render said texture to a screen-filling quad. This ...
2
votes
2
answers
291
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OpenGLES Alpha value modifies rgb values when reading them out with glReadPixels
When reading out rgba(1,1,1,0.1) with glReadPixels will result in rgba(0.1,0.1,0.1,???). The function is reading modified values from the framebuffer, I assume because of alpha blending.
The example I'...
- 3,113
1
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1
answer
171
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Can you glBlitFramebuffer between different levels of the same texture?
Let's say I have a texture that I need to mipmap but I want the mipmapping done hardware accelerated. I decided the best route to take would be something like this:
int read = glGenFramebuffers();
...
- 174
0
votes
1
answer
449
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Vulkan/OpenGL subpasses that fetch more than single fragment
So, Vulkan introduced subpasses and opengl implelemts similar behaviour with ARM_framebuffer_fetch
In the past, I have used framebuffer_fetch successfully for tonemapping post-effect shaders.
Back ...
- 4,903
0
votes
1
answer
1k
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Rendering to custom FrameBuffer using same texture both as input and output
Some Fragment shaders in ShaderToy (e.g. fluid dynamics, https://www.shadertoy.com/view/4tGfDW ) use same buffer as both input and output. But when I try to do this in my C/C++ code it does not work (...
- 2,434
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294
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Read from framebuffer on Android
I try to get data from default framebuffer on Android (GLES 3.1). Andriod version 6.0. Device: Levono TAB 2 A-10.
If I use glReadPixels it works fine, but I want to avoid copying data to the CPU and ...
0
votes
0
answers
264
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iOS OpenglES 3.0 rendering to texture fails with depth attachment
Rendering into texture in my mobile app works fine when the rendertarget texture has no depth attachment. When I add a depth attachment, it stops working on iOS. Apparently can't switch back to the ...
0
votes
1
answer
637
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How to fix strange artifacts when applying Gaussian blur in OpenGL ES 2.0
I am getting strange artifacts when applying Gaussian Blur for a bloom effect in OpenGL ES 2.0 (with QT), as you can see below. On the left is with the bloom effect enabled, and on the right is with ...
- 435
2
votes
1
answer
1k
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How to overcome differences between off-screen and on-screen framebuffer rendering?
I'm trying to use an off-screen framebuffer to replicate a scene that renders wonderfully to the default framebuffer. There seem to be differences in the rendering that I can't sort out.
For context,...
- 435
2
votes
1
answer
423
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Opengl ES 2.0 glDeleteFramebuffers after drawing to texture
I render to texture using frame buffer. But I am not sure when should I correctly use glDeleteFramebuffers. Should fbo exist while texture exists, or can I safely call glDeleteFramebuffers after last ...
- 847
3
votes
1
answer
2k
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Saving a glTexImage2D to the file system for inspection
I have a 3D graphics application that is exhibiting bad texturing behavior (specifically: a specific texture is showing up as black when it shouldn't be). I have isolated the texture data in the ...
- 7,227
1
vote
1
answer
368
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Partial redraw to FBO OpenGL
My scene is organized into groups of elements that compose to FBOs backed by floating point textures (16 bit with alpha). These FBOs are then blended together top to bottom to produce the final scene. ...
- 327
0
votes
1
answer
219
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OpenGL 3.0 ES - Disjoint read and write from same texture
I'm in a situation where I have a (n+1)x(n+1) texture attached to a framebuffer.
My idea is to update this texture in 2 passes.
Draw a full screen quad and use the scissor test to mask out the ...
- 55