jrepin writes "New functionality in the OpenGL 4.2 specification of high-performance graphics standard includes: Enabling shaders with atomic counters and load/store/atomic read-modify-write operations to a single level of a texture. These capabilities can be combined, for example, to maintain a counter at each pixel in a buffer object for single-rendering-pass order-independent transparency. Capturing GPU-tessellated geometry and drawing multiple instances of the result of a transform feedback to enable complex objects to be efficiently repositioned and replicated. Modifying an arbitrary subset of a compressed texture, without having to re-download the whole texture to the GPU for significant performance improvements. Packing multiple 8 and 16 bit values into a single 32-bit value for efficient shader processing with significantly reduced memory storage and bandwidth, especially useful when transferring data between shader stages."
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