I share my knowledge about computer graphics and math here, the best way I can.https://erfan-ahmadi.github.io/enhttps://erfan-ahmadi.github.io/blog/screen-space-derivatives-in-practice/https://erfan-ahmadi.github.io/blog/screen-space-derivatives-in-practice/Screen-space derivatives are built into every GPU and available in fragment shader, yet few people know how and when they should use them.Tue, 20 Oct 2026 00:00:00 GMTShadersMathSDFhttps://erfan-ahmadi.github.io/blog/simplex/https://erfan-ahmadi.github.io/blog/simplex/Deriving the 2D “squash” transform behind simplex noise that turns a square grid into equilateral triangles — a proof instead of magic numbers.Tue, 11 Mar 2025 00:00:00 GMTMathShadershttps://erfan-ahmadi.github.io/blog/frames-in-flight/https://erfan-ahmadi.github.io/blog/frames-in-flight/What “frames in flight” really means, how to drive it with timeline semaphores, and how swapchain images limit it.Sun, 10 Nov 2024 00:00:00 GMTVulkanSynchronizationNablahttps://erfan-ahmadi.github.io/blog/texture-upload/https://erfan-ahmadi.github.io/blog/texture-upload/The Nabla utility that streams large textures to the GPU in batches through a fixed-size staging buffer, converting formats on the fly.Tue, 29 Nov 2022 00:00:00 GMTVulkanNablahttps://erfan-ahmadi.github.io/blog/yugen-render-targets/https://erfan-ahmadi.github.io/blog/yugen-render-targets/Weighing designs for one render-target abstraction over Vulkan render passes and D3D12, from framebuffers to imageless framebuffers.Sun, 09 Aug 2020 00:00:00 GMTVulkanD3D12Enginehttps://erfan-ahmadi.github.io/blog/yugen-compute-demo/https://erfan-ahmadi.github.io/blog/yugen-compute-demo/Multi-queue submission lands in our renderer backend: two million cubes animated in a compute pass and drawn instanced.Fri, 31 Jul 2020 00:00:00 GMTVulkanComputehttps://erfan-ahmadi.github.io/blog/yugen-asset-system/https://erfan-ahmadi.github.io/blog/yugen-asset-system/YUGA, our chunked asset file format for meshes, textures and shaders, and how shader reflection data is stored inside it.Wed, 15 Jul 2020 00:00:00 GMTEngineShadershttps://erfan-ahmadi.github.io/blog/yugen-rendering-system/https://erfan-ahmadi.github.io/blog/yugen-rendering-system/Kicking off a journal on building the rendering system of Yugen, our in-house engine: the Vulkan backend, the demo framework and what comes next.Sat, 11 Jul 2020 00:00:00 GMTVulkanEnginehttps://erfan-ahmadi.github.io/blog/bokeh-depth-of-field/https://erfan-ahmadi.github.io/blog/bokeh-depth-of-field/Three ways to render bokeh depth of field: circular separable DoF, practical gather-based bokeh, and single-pass depth of field.Thu, 31 Oct 2019 00:00:00 GMTPost-processingThe Forgehttps://erfan-ahmadi.github.io/blog/the-forge-examples/https://erfan-ahmadi.github.io/blog/the-forge-examples/Weekend experiments on The Forge: instancing, Blinn-Phong lighting, deferred shading, toon shading, tessellation and bloom.Thu, 26 Sep 2019 00:00:00 GMTThe ForgeShadershttps://erfan-ahmadi.github.io/blog/introduction/https://erfan-ahmadi.github.io/blog/introduction/Who I am, why I wanted to build engines instead of just using them, and why I started this blog.Thu, 04 Apr 2019 00:00:00 GMTPersonal