Freedesktop

Two more dEQP tests down: dEQP-GLES3.functional.fbo.blit.rect.nearest_consistency_mag -- Pass dEQP-GLES3.functional.fbo.blit.rect.nearest_consistency_min -- Pass This one was a fun geometry puzzle. The problem Mesa’s u_blitter is the utility that drivers use for framebuffer blits – copying pixel data between surfaces, optionally scaling and filtering. It works by drawing a textured quad: set up the source as a texture, the destination as a render target, and draw a rectangle with the appropriate texture coordinates. Simple. ...

If you’ve ever looked at a GPU render and seen blue where red should be, you’ve met the R/B swap problem. For etnaviv this has been a long-standing source of complexity. We were solving it in the shader, but the proprietary blob driver had a simpler approach all along. As part of my work at Igalia, I finally sat down and did it properly. The problem Vivante GPUs have a quirk: the Pixel Engine (PE) always writes pixels in BGRA byte order. When your API says “render to R8G8B8A8_UNORM”, what actually lands in memory is B, G, R, A. Every byte of every pixel, every frame. The hardware just works that way. ...

This is the start of a series about getting OpenGL ES 3.0 conformance on Vivante GC7000 hardware using the open-source etnaviv driver in Mesa. Thanks to Igalia for giving me the opportunity to spend some time on these topics. Where We Are etnaviv has supported GLES2 on Vivante GPUs for a long time. GLES3 support has been progressing steadily, but the remaining dEQP failures are the stubborn ones - the cases where the hardware doesn’t quite do what the spec says, and the driver has to get creative. ...

After years of working on etnaviv - a Gallium/OpenGL driver for Vivante GPUs - I’ve been wanting to get into Vulkan. As part of my work at Igalia, the goal was to bring VK_EXT_blend_operation_advanced to lavapipe. But rather than going straight there, I started with Honeykrisp - the Vulkan driver for Apple Silicon - as a first target: a real hardware driver to validate the implementation against before wiring it up in a software renderer. My first Vulkan extension, and my first real contribution to Honeykrisp. ...

Modern graphics programming revolves around achieving high-performance rendering and visually stunning effects. Among OpenGL’s capabilities, Multiple Render Targets (MRTs) are particularly valuable for enabling advanced rendering techniques with greater efficiency. With the latest release of Mesa 24.03 and the commitment from Igalia, the etnaviv GPU driver now includes support for MRTs. If you’ve ever wondered how MRTs can transform your graphics pipeline or are curious about the challenges of implementing this feature, this blog post is for you. ...