OpenGL
OpenGL conditional rendering bug on MacOS X
At least on Intel HD4000 GPUs there seems to be a bug regarding conditional rendering in OpenGL on 10.8 Mountain Lion: After the conditional rendering the condition state (ignore draw calls or execute them) is ‘stuck’ until the next draw call gets issued – this can ignore glClear calls which shouldn’t get ignored. Here’s an [...]
GLSL Syntax Highlighting for TextWrangler & BBEdit
I hacked together a very simple codeless language module for TextWrangler (also compatible with BBEdit) for GLSL shaders. It is much simpler than the Kate/QTCreator highlighting and only highlights GLSL version 430 (core profile) but it’s better than nothing (In case you are writing shaders for OpenGL ES 3.0, or OpenGL 3.0 – 4.2 it [...]
GLSL Syntax Highlighting for QTCreator (and Kate)
The syntax highlighter in QTCreator for GLSL shaders is currently far from ideal: It’s basically stuck at OpenGL 2.1. If you write shaders for OpenGL 3 (and later) or OpenGL ES 3, you will see a lot of red marks indicating errors in your code simply because QTCreator doesn’t know the latest keywords. On the [...]
Noperspective varying interpolation bug on MacOS X
There seems to be a bug with noperspective varyings in OpenGL 3.2 contexts on MacOS X on Intel HD4000 hardware: The varying does not get interpolated and all fragments of the triangle get the same value (similar to flat interpolation). Note that in the left screen shot the image looks similar to perspective correct interpolated texture [...]
First hints of OpenGL 4 on MacOS X?
No Mac currently supports more than OpenGL 3.2 even tho all current Macs could support OpenGL 4.x. Apple doesn’t comment on this situation but it seems, that at least some features of newer GL versions made it into the drivers. The lastest GLSL version MacOS supports is 150, at least that’s what glGetString(GL_SHADING_LANGUAGE_VERSION) tells us. [...]
Which GPUs support OpenGL ES 3.0?
With OpenGL ES 3 (codename Halti) was just released, the question arrises who will be the first to provide hardware support in there mobile GPUs. In fact, there are already some chips in the pipeline that support all the features necessary so we could see full ES3 support soon: PowerVR Series5 SGX545 from ImgTec, announced [...]
OpenGL 4.3 released
In addition to OpenGL ES 3.0 Khronos also released OpenGL 4.3 today. The latest incarnation of the desktop variant of this rendering API comes with some surprises. OpenGL 4.1 added ES 2 compatibility, so from 2010 onwards GL was a superset of the embedded version. While ES 3 is based on GL 3.3 (without geometry [...]
OpenGL ES 3.0 – Halti has arrived
Khronos just released the specs for OpenGL ES 3.0 during Siggraph earlier today. Rumors were going on for some time and Khronos announced that they will release something. Back in May I wrote “The best thing we can hope for is a clean rewrite of the specification text and OpenGL ES 3.0 – ideally in the same [...]
MacOS X OpenGL driver bugs
Once in a while I run across a bug in Apples OpenGL implementation. Providing an up-to-date and performant OpenGL implementation is not an easy task, and you have to wonder why Apple tries to do this on there own and not letting Intel, NVidia and AMD provide the drivers as they do on Windows and [...]
Mac OpenGL capabilities
The latest MacBook Pro just got a GeForce 650M – a Kepler based GPU. This chip is not only capable of delivering OpenGL 4.2 but also shiny new features like bindless textures: one way of supporting Virtual Texturing in hardware and maybe something we will see in some form in OpenGL 5.0. This makes it [...]