From d9503632d43dfa026d72334da5fcb33387550a67 Mon Sep 17 00:00:00 2001
From: cosmonaut <evan@moonside.games>
Date: Wed, 9 Oct 2024 21:19:48 -0700
Subject: [PATCH] GPU: Add SDL_CalculateGPUTextureFormatSize

---
 include/SDL3/SDL_gpu.h            | 17 +++++++++++++++++
 src/dynapi/SDL_dynapi.sym         |  1 +
 src/dynapi/SDL_dynapi_overrides.h |  1 +
 src/dynapi/SDL_dynapi_procs.h     |  1 +
 src/gpu/SDL_gpu.c                 | 13 +++++++++++++
 src/gpu/SDL_sysgpu.h              | 15 ---------------
 src/gpu/metal/SDL_gpu_metal.m     |  2 +-
 7 files changed, 34 insertions(+), 16 deletions(-)

diff --git a/include/SDL3/SDL_gpu.h b/include/SDL3/SDL_gpu.h
index b9e7442f995e6f..210330fe49394d 100644
--- a/include/SDL3/SDL_gpu.h
+++ b/include/SDL3/SDL_gpu.h
@@ -3715,6 +3715,23 @@ extern SDL_DECLSPEC bool SDLCALL SDL_GPUTextureSupportsSampleCount(
     SDL_GPUTextureFormat format,
     SDL_GPUSampleCount sample_count);
 
+/**
+ * Calculate the size in bytes of a texture format with dimensions.
+ *
+ * \param format a texture format.
+ * \param width width in pixels.
+ * \param height height in pixels.
+ * \param depth depth in pixels.
+ * \returns the size of a texture with this format and dimensions.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC Uint32 SDLCALL SDL_CalculateGPUTextureFormatSize(
+    SDL_GPUTextureFormat format,
+    Uint32 width,
+    Uint32 height,
+    Uint32 depth);
+
 #ifdef SDL_PLATFORM_GDK
 
 /**
diff --git a/src/dynapi/SDL_dynapi.sym b/src/dynapi/SDL_dynapi.sym
index c60e930c03666a..06cc432a93f958 100644
--- a/src/dynapi/SDL_dynapi.sym
+++ b/src/dynapi/SDL_dynapi.sym
@@ -1178,6 +1178,7 @@ SDL3_0.0.0 {
     SDL_wcstol;
     SDL_StepBackUTF8;
     SDL_DelayPrecise;
+    SDL_CalculateGPUTextureFormatSize;
     # extra symbols go here (don't modify this line)
   local: *;
 };
diff --git a/src/dynapi/SDL_dynapi_overrides.h b/src/dynapi/SDL_dynapi_overrides.h
index c03a633f12739f..6de3884830abff 100644
--- a/src/dynapi/SDL_dynapi_overrides.h
+++ b/src/dynapi/SDL_dynapi_overrides.h
@@ -1203,3 +1203,4 @@
 #define SDL_wcstol SDL_wcstol_REAL
 #define SDL_StepBackUTF8 SDL_StepBackUTF8_REAL
 #define SDL_DelayPrecise SDL_DelayPrecise_REAL
+#define SDL_CalculateGPUTextureFormatSize SDL_CalculateGPUTextureFormatSize_REAL
diff --git a/src/dynapi/SDL_dynapi_procs.h b/src/dynapi/SDL_dynapi_procs.h
index 59c32eaaf55b5e..e6dcb8b8028ba5 100644
--- a/src/dynapi/SDL_dynapi_procs.h
+++ b/src/dynapi/SDL_dynapi_procs.h
@@ -1209,3 +1209,4 @@ SDL_DYNAPI_PROC(wchar_t*,SDL_wcsstr,(const wchar_t *a, const wchar_t *b),(a,b),r
 SDL_DYNAPI_PROC(long,SDL_wcstol,(const wchar_t *a, wchar_t **b, int c),(a,b,c),return)
 SDL_DYNAPI_PROC(Uint32,SDL_StepBackUTF8,(const char *a, const char **b),(a,b),return)
 SDL_DYNAPI_PROC(void,SDL_DelayPrecise,(Uint64 a),(a),)
+SDL_DYNAPI_PROC(Uint32,SDL_CalculateGPUTextureFormatSize,(SDL_GPUTextureFormat a, Uint32 b, Uint32 c, Uint32 d),(a,b,c,d),return)
diff --git a/src/gpu/SDL_gpu.c b/src/gpu/SDL_gpu.c
index 3607a7954063ff..89eb0ce6a19161 100644
--- a/src/gpu/SDL_gpu.c
+++ b/src/gpu/SDL_gpu.c
@@ -2796,3 +2796,16 @@ void SDL_ReleaseGPUFence(
         device->driverData,
         fence);
 }
+
+Uint32 SDL_CalculateGPUTextureFormatSize(
+    SDL_GPUTextureFormat format,
+    Uint32 width,
+    Uint32 height,
+    Uint32 depth)
+{
+    Uint32 pixelRowsPerBlock = Texture_GetBlockSize(format);
+    Uint32 pixelColumnsPerBlock = pixelRowsPerBlock;
+    Uint32 blocksPerRow = (width + pixelRowsPerBlock - 1) / pixelRowsPerBlock;
+    Uint32 blocksPerColumn = (height + pixelColumnsPerBlock - 1) / pixelColumnsPerBlock;
+    return depth * blocksPerRow * blocksPerColumn * SDL_GPUTextureFormatTexelBlockSize(format);
+}
diff --git a/src/gpu/SDL_sysgpu.h b/src/gpu/SDL_sysgpu.h
index ba48c6cc1cc169..0c0db5e920895f 100644
--- a/src/gpu/SDL_sysgpu.h
+++ b/src/gpu/SDL_sysgpu.h
@@ -208,21 +208,6 @@ static inline Uint32 BytesPerRow(
     return blocksPerRow * SDL_GPUTextureFormatTexelBlockSize(format);
 }
 
-static inline Sint32 BytesPerImage(
-    Uint32 width,
-    Uint32 height,
-    SDL_GPUTextureFormat format)
-{
-    Uint32 blocksPerRow = width;
-    Uint32 blocksPerColumn = height;
-    Uint32 pixelRowsPerBlock = Texture_GetBlockSize(format);
-    Uint32 pixelColumnsPerBlock = pixelRowsPerBlock;
-
-    blocksPerRow = (width + pixelRowsPerBlock - 1) / pixelRowsPerBlock;
-    blocksPerColumn = (height + pixelColumnsPerBlock - 1) / pixelColumnsPerBlock;
-    return blocksPerRow * blocksPerColumn * SDL_GPUTextureFormatTexelBlockSize(format);
-}
-
 // GraphicsDevice Limits
 
 #define MAX_TEXTURE_SAMPLERS_PER_STAGE 16
diff --git a/src/gpu/metal/SDL_gpu_metal.m b/src/gpu/metal/SDL_gpu_metal.m
index 84515eaf025dab..f405c91fe842f5 100644
--- a/src/gpu/metal/SDL_gpu_metal.m
+++ b/src/gpu/metal/SDL_gpu_metal.m
@@ -1752,7 +1752,7 @@ static void METAL_UploadToTexture(
                  copyFromBuffer:bufferContainer->activeBuffer->handle
                    sourceOffset:source->offset
               sourceBytesPerRow:BytesPerRow(destination->w, textureContainer->header.info.format)
-            sourceBytesPerImage:BytesPerImage(destination->w, destination->h, textureContainer->header.info.format)
+            sourceBytesPerImage:SDL_CalculateGPUTextureFormatSize(textureContainer->header.info.format, destination->w, destination->h, destination->d)
                      sourceSize:MTLSizeMake(destination->w, destination->h, destination->d)
                       toTexture:metalTexture->handle
                destinationSlice:destination->layer