SDL: Sync SDL3 wiki -> header (d6a95)

From d6a95ae198820329dbd82311bbd75e06d3412ed5 Mon Sep 17 00:00:00 2001
From: SDL Wiki Bot <[EMAIL REDACTED]>
Date: Thu, 19 Dec 2024 18:54:59 +0000
Subject: [PATCH] Sync SDL3 wiki -> header

[ci skip]
---
 include/SDL3/SDL_gpu.h | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/include/SDL3/SDL_gpu.h b/include/SDL3/SDL_gpu.h
index 839b134db34f7..814076e98f485 100644
--- a/include/SDL3/SDL_gpu.h
+++ b/include/SDL3/SDL_gpu.h
@@ -2197,6 +2197,14 @@ extern SDL_DECLSPEC SDL_GPUSampler *SDLCALL SDL_CreateGPUSampler(
  *   [[stage_in]] attribute which will automatically use the vertex input
  *   information from the SDL_GPUGraphicsPipeline.
  *
+ * Shader semantics do not matter in D3D12 and for ease of use the SDL
+ * implementation assumes that they will all be TEXCOORD. If you are using
+ * HLSL as the shader source language, your vertex semantics should start at
+ * TEXCOORD0 and increment like so: TEXCOORD1, TEXCOORD2, etc. If you wish to
+ * change the semantic prefix to something other than TEXCOORD you can use
+ * SDL_PROP_GPU_DEVICE_CREATE_D3D12_SEMANTIC_NAME_STRING with
+ * SDL_CreateGPUDeviceWithProperties().
+ *
  * \param device a GPU Context.
  * \param createinfo a struct describing the state of the shader to create.
  * \returns a shader object on success, or NULL on failure; call