SDL: Fix D3D12 DSV creation for array/cube/cube-array depth textures

SDL Commits
1 
From a79bd26d28bcf8aaa65374bc611fc83ae8574dc5 Mon Sep 17 00:00:00 2001
From: Jesse Chounard <[EMAIL REDACTED]>
Date: Thu, 19 Feb 2026 07:42:04 -0600
Subject: [PATCH] Fix D3D12 DSV creation for array/cube/cube-array depth
 textures

DSV creation was missing a TEXTURE2DARRAY branch for array, cube, and
cube-array depth textures. It fell through to TEXTURE2D, so
FirstArraySlice was never set and all layers' DSVs targeted layer 0.
This caused incorrect rendering when using depth textures with multiple
layers, such as cubemap shadow maps.
---
 src/gpu/d3d12/SDL_gpu_d3d12.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/gpu/d3d12/SDL_gpu_d3d12.c b/src/gpu/d3d12/SDL_gpu_d3d12.c
index a2190f7ccdb8e..4316603c629a4 100644
--- a/src/gpu/d3d12/SDL_gpu_d3d12.c
+++ b/src/gpu/d3d12/SDL_gpu_d3d12.c
@@ -3646,7 +3646,12 @@ static D3D12Texture *D3D12_INTERNAL_CreateTexture(
                 dsvDesc.Format = SDLToD3D12_DepthFormat[createinfo->format];
                 dsvDesc.Flags = (D3D12_DSV_FLAGS)0;
 
-                if (isMultisample) {
+                if (createinfo->type == SDL_GPU_TEXTURETYPE_2D_ARRAY || createinfo->type == SDL_GPU_TEXTURETYPE_CUBE || createinfo->type == SDL_GPU_TEXTURETYPE_CUBE_ARRAY) {
+                    dsvDesc.ViewDimension = D3D12_DSV_DIMENSION_TEXTURE2DARRAY;
+                    dsvDesc.Texture2DArray.MipSlice = levelIndex;
+                    dsvDesc.Texture2DArray.FirstArraySlice = layerIndex;
+                    dsvDesc.Texture2DArray.ArraySize = 1;
+                } else if (isMultisample) {
                     dsvDesc.ViewDimension = D3D12_DSV_DIMENSION_TEXTURE2DMS;
                 } else {
                     dsvDesc.ViewDimension = D3D12_DSV_DIMENSION_TEXTURE2D;