From 4a4ae4a79d3522b9ba6b0f5cbfdcb825cdf959f7 Mon Sep 17 00:00:00 2001
From: Void Star Caster <[EMAIL REDACTED]>
Date: Tue, 24 Feb 2026 17:05:30 +0100
Subject: [PATCH] Fix GetSampler() bug for INDEX8 pixel format (#15099)
---
src/render/direct3d11/SDL_render_d3d11.c | 12 ++++++------
src/render/direct3d12/SDL_render_d3d12.c | 12 ++++++------
src/render/gpu/SDL_render_gpu.c | 18 ++++++++----------
src/render/metal/SDL_render_metal.m | 15 +++++++--------
src/render/vulkan/SDL_render_vulkan.c | 15 +++++++--------
5 files changed, 34 insertions(+), 38 deletions(-)
diff --git a/src/render/direct3d11/SDL_render_d3d11.c b/src/render/direct3d11/SDL_render_d3d11.c
index 30943aeb4805e..131a770251f22 100644
--- a/src/render/direct3d11/SDL_render_d3d11.c
+++ b/src/render/direct3d11/SDL_render_d3d11.c
@@ -2395,6 +2395,11 @@ static bool D3D11_SetDrawState(SDL_Renderer *renderer, const SDL_RenderCommand *
static ID3D11SamplerState *D3D11_GetSamplerState(D3D11_RenderData *data, SDL_PixelFormat format, SDL_ScaleMode scale_mode, SDL_TextureAddressMode address_u, SDL_TextureAddressMode address_v)
{
+ if (format == SDL_PIXELFORMAT_INDEX8) {
+ // We'll do linear sampling in the shader if needed
+ scale_mode = SDL_SCALEMODE_NEAREST;
+ }
+
Uint32 key = RENDER_SAMPLER_HASHKEY(scale_mode, address_u, address_v);
SDL_assert(key < SDL_arraysize(data->samplers));
if (!data->samplers[key]) {
@@ -2412,12 +2417,7 @@ static ID3D11SamplerState *D3D11_GetSamplerState(D3D11_RenderData *data, SDL_Pix
break;
case SDL_SCALEMODE_PIXELART: // Uses linear sampling
case SDL_SCALEMODE_LINEAR:
- if (format == SDL_PIXELFORMAT_INDEX8) {
- // We'll do linear sampling in the shader
- samplerDesc.Filter = D3D11_FILTER_MIN_MAG_MIP_POINT;
- } else {
- samplerDesc.Filter = D3D11_FILTER_MIN_MAG_MIP_LINEAR;
- }
+ samplerDesc.Filter = D3D11_FILTER_MIN_MAG_MIP_LINEAR;
break;
default:
SDL_SetError("Unknown scale mode: %d", scale_mode);
diff --git a/src/render/direct3d12/SDL_render_d3d12.c b/src/render/direct3d12/SDL_render_d3d12.c
index 0eb39872157de..92b170d8a7ba6 100644
--- a/src/render/direct3d12/SDL_render_d3d12.c
+++ b/src/render/direct3d12/SDL_render_d3d12.c
@@ -2838,6 +2838,11 @@ static bool D3D12_SetDrawState(SDL_Renderer *renderer, const SDL_RenderCommand *
static D3D12_CPU_DESCRIPTOR_HANDLE *D3D12_GetSamplerState(D3D12_RenderData *data, SDL_PixelFormat format, SDL_ScaleMode scale_mode, SDL_TextureAddressMode address_u, SDL_TextureAddressMode address_v)
{
+ if (format == SDL_PIXELFORMAT_INDEX8) {
+ // We'll do linear sampling in the shader if needed
+ scale_mode = SDL_SCALEMODE_NEAREST;
+ }
+
Uint32 key = RENDER_SAMPLER_HASHKEY(scale_mode, address_u, address_v);
SDL_assert(key < SDL_arraysize(data->samplers));
if (!data->samplers_created[key]) {
@@ -2863,12 +2868,7 @@ static D3D12_CPU_DESCRIPTOR_HANDLE *D3D12_GetSamplerState(D3D12_RenderData *data
break;
case SDL_SCALEMODE_PIXELART: // Uses linear sampling
case SDL_SCALEMODE_LINEAR:
- if (format == SDL_PIXELFORMAT_INDEX8) {
- // We'll do linear sampling in the shader
- samplerDesc.Filter = D3D12_FILTER_MIN_MAG_MIP_POINT;
- } else {
- samplerDesc.Filter = D3D12_FILTER_MIN_MAG_MIP_LINEAR;
- }
+ samplerDesc.Filter = D3D12_FILTER_MIN_MAG_MIP_LINEAR;
break;
default:
SDL_SetError("Unknown scale mode: %d", scale_mode);
diff --git a/src/render/gpu/SDL_render_gpu.c b/src/render/gpu/SDL_render_gpu.c
index cf6cd9248c984..c918ac3b0662e 100644
--- a/src/render/gpu/SDL_render_gpu.c
+++ b/src/render/gpu/SDL_render_gpu.c
@@ -790,6 +790,11 @@ static void SetViewportAndScissor(GPU_RenderData *data)
static SDL_GPUSampler *GetSampler(GPU_RenderData *data, SDL_PixelFormat format, SDL_ScaleMode scale_mode, SDL_TextureAddressMode address_u, SDL_TextureAddressMode address_v)
{
+ if (format == SDL_PIXELFORMAT_INDEX8) {
+ // We'll do linear sampling in the shader if needed
+ scale_mode = SDL_SCALEMODE_NEAREST;
+ }
+
Uint32 key = RENDER_SAMPLER_HASHKEY(scale_mode, address_u, address_v);
SDL_assert(key < SDL_arraysize(data->samplers));
if (!data->samplers[key]) {
@@ -803,16 +808,9 @@ static SDL_GPUSampler *GetSampler(GPU_RenderData *data, SDL_PixelFormat format,
break;
case SDL_SCALEMODE_PIXELART: // Uses linear sampling
case SDL_SCALEMODE_LINEAR:
- if (format == SDL_PIXELFORMAT_INDEX8) {
- // We'll do linear sampling in the shader
- sci.min_filter = SDL_GPU_FILTER_NEAREST;
- sci.mag_filter = SDL_GPU_FILTER_NEAREST;
- sci.mipmap_mode = SDL_GPU_SAMPLERMIPMAPMODE_NEAREST;
- } else {
- sci.min_filter = SDL_GPU_FILTER_LINEAR;
- sci.mag_filter = SDL_GPU_FILTER_LINEAR;
- sci.mipmap_mode = SDL_GPU_SAMPLERMIPMAPMODE_LINEAR;
- }
+ sci.min_filter = SDL_GPU_FILTER_LINEAR;
+ sci.mag_filter = SDL_GPU_FILTER_LINEAR;
+ sci.mipmap_mode = SDL_GPU_SAMPLERMIPMAPMODE_LINEAR;
break;
default:
SDL_SetError("Unknown scale mode: %d", scale_mode);
diff --git a/src/render/metal/SDL_render_metal.m b/src/render/metal/SDL_render_metal.m
index 5c1a3dc2f79dc..8aa78522ae604 100644
--- a/src/render/metal/SDL_render_metal.m
+++ b/src/render/metal/SDL_render_metal.m
@@ -1584,6 +1584,11 @@ static bool SetDrawState(SDL_Renderer *renderer, const SDL_RenderCommand *cmd, c
static id<MTLSamplerState> GetSampler(SDL3METAL_RenderData *data, SDL_PixelFormat format, SDL_ScaleMode scale_mode, SDL_TextureAddressMode address_u, SDL_TextureAddressMode address_v)
{
+ if (format == SDL_PIXELFORMAT_INDEX8) {
+ // We'll do linear sampling in the shader if needed
+ scale_mode = SDL_SCALEMODE_NEAREST;
+ }
+
NSNumber *key = [NSNumber numberWithInteger:RENDER_SAMPLER_HASHKEY(scale_mode, address_u, address_v)];
id<MTLSamplerState> mtlsampler = data.mtlsamplers[key];
if (mtlsampler == nil) {
@@ -1596,14 +1601,8 @@ static bool SetDrawState(SDL_Renderer *renderer, const SDL_RenderCommand *cmd, c
break;
case SDL_SCALEMODE_PIXELART: // Uses linear sampling
case SDL_SCALEMODE_LINEAR:
- if (format == SDL_PIXELFORMAT_INDEX8) {
- // We'll do linear sampling in the shader
- samplerdesc.minFilter = MTLSamplerMinMagFilterNearest;
- samplerdesc.magFilter = MTLSamplerMinMagFilterNearest;
- } else {
- samplerdesc.minFilter = MTLSamplerMinMagFilterLinear;
- samplerdesc.magFilter = MTLSamplerMinMagFilterLinear;
- }
+ samplerdesc.minFilter = MTLSamplerMinMagFilterLinear;
+ samplerdesc.magFilter = MTLSamplerMinMagFilterLinear;
break;
default:
SDL_SetError("Unknown scale mode: %d", scale_mode);
diff --git a/src/render/vulkan/SDL_render_vulkan.c b/src/render/vulkan/SDL_render_vulkan.c
index ec03b62f9d1fc..ad434ff6727af 100644
--- a/src/render/vulkan/SDL_render_vulkan.c
+++ b/src/render/vulkan/SDL_render_vulkan.c
@@ -3870,6 +3870,11 @@ static bool VULKAN_SetDrawState(SDL_Renderer *renderer, const SDL_RenderCommand
static VkSampler VULKAN_GetSampler(VULKAN_RenderData *data, SDL_PixelFormat format, SDL_ScaleMode scale_mode, SDL_TextureAddressMode address_u, SDL_TextureAddressMode address_v)
{
+ if (format == SDL_PIXELFORMAT_INDEX8) {
+ // We'll do linear sampling in the shader if needed
+ scale_mode = SDL_SCALEMODE_NEAREST;
+ }
+
Uint32 key = RENDER_SAMPLER_HASHKEY(scale_mode, address_u, address_v);
SDL_assert(key < SDL_arraysize(data->samplers));
if (!data->samplers[key]) {
@@ -3889,14 +3894,8 @@ static VkSampler VULKAN_GetSampler(VULKAN_RenderData *data, SDL_PixelFormat form
break;
case SDL_SCALEMODE_PIXELART: // Uses linear sampling
case SDL_SCALEMODE_LINEAR:
- if (format == SDL_PIXELFORMAT_INDEX8) {
- // We'll do linear sampling in the shader
- samplerCreateInfo.magFilter = VK_FILTER_NEAREST;
- samplerCreateInfo.minFilter = VK_FILTER_NEAREST;
- } else {
- samplerCreateInfo.magFilter = VK_FILTER_LINEAR;
- samplerCreateInfo.minFilter = VK_FILTER_LINEAR;
- }
+ samplerCreateInfo.magFilter = VK_FILTER_LINEAR;
+ samplerCreateInfo.minFilter = VK_FILTER_LINEAR;
break;
default:
SDL_SetError("Unknown scale mode: %d", scale_mode);