[OpenGL/Vulkan/DX12]Firefly and Banding Artifacts with High-Intensity HDR

[CubeBerry]

What is an issue?

When using HDR textures with extremely high Dynamic Range (e.g., 0 ~ 160,000) for Skybox and IBL (Image Based Lighting), severe Firefly artifacts and surface Banding (ripple-like patterns) appear in the rendered output.

Expected Causes

None.

Expected Solutions

Replaced hdr image of small range (Approximately 0 ~ 100) to avoid artifacts due to strong intensity of wide range (Approximately 0 ~ over 100) temporarily.

[CubeBerry]

ef13add

Added sampler.MaxLOD = D3D12_FLOAT32_MAX in PrefilteredEnvironmentMap() function in DXSkybox.cpp to allow sampling across all mip levels of the cubemap, which is essential for accurate prefiltering results.

D3D12_STATIC_SAMPLER_DESC sampler = {};
sampler.Filter = D3D12_FILTER_MIN_MAG_MIP_LINEAR;
sampler.AddressU = D3D12_TEXTURE_ADDRESS_MODE_CLAMP;
sampler.AddressV = D3D12_TEXTURE_ADDRESS_MODE_CLAMP;
sampler.AddressW = D3D12_TEXTURE_ADDRESS_MODE_CLAMP;
// MinLOD and MaxLOD are set to allow sampling across all mip levels of the cubemap, which is essential for accurate prefiltering results
sampler.MinLOD = 0.0f;
sampler.MaxLOD = D3D12_FLOAT32_MAX;
sampler.ShaderRegister = 0;
sampler.RegisterSpace = 1;
sampler.ShaderVisibility = D3D12_SHADER_VISIBILITY_PIXEL;

[CubeBerry]

Reopened this issue because It should be fixed on OpenGL and Vulkan.