From fc88859eaf0adde7ae700ca7fbc3a4f88ed5443c Mon Sep 17 00:00:00 2001
From: Sven Balzer <4653051+Kyuusokuna@users.noreply.github.com>
Date: Mon, 17 Mar 2025 08:17:54 +0100
Subject: [PATCH] only upload data to texture if *data is not NULL

refactor create_shader_texture(path) to use the other create_shader_texture(name, data, width. height, channels)
---
 src/main.cpp | 228 +++++++++++++++++----------------------------------
 1 file changed, 73 insertions(+), 155 deletions(-)

diff --git a/src/main.cpp b/src/main.cpp
index 8c6dae2..cb2f90d 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -372,110 +372,6 @@ static void change_map_size(char direction, int amount) {
     SDL_ReleaseGPUBuffer(device, old_world_buffer);
 }
 
-static SDL_GPUTexture *create_shader_texture(const char *path) {
-    int width = 0, height = 0, channels = 0; 
-    stbi_uc *data = stbi_load(path, &width, &height, &channels, 0);
-    if (!data) {
-        log_error("Failed to load texture (\"%s\").", path);
-        return NULL;
-    }
-
-    SDL_GPUTextureFormat format = SDL_GPU_TEXTUREFORMAT_INVALID;
-    if (channels == 1) format = SDL_GPU_TEXTUREFORMAT_A8_UNORM;
-    if (channels == 4) format = SDL_GPU_TEXTUREFORMAT_R8G8B8A8_UNORM_SRGB;
-
-    if (format == SDL_GPU_TEXTUREFORMAT_INVALID) {
-        log_error("Failed to find texture format for texture (\"%s\").", path);
-        stbi_image_free(data);
-        return NULL;
-    }
-
-    SDL_PropertiesID properties = SDL_CreateProperties();
-    if (properties) SDL_SetStringProperty(properties, SDL_PROP_GPU_TEXTURE_CREATE_NAME_STRING, path);
-
-    SDL_GPUTextureCreateInfo texture_info = {
-        .type   = SDL_GPU_TEXTURETYPE_2D,
-        .format = format,
-        .usage  = SDL_GPU_TEXTUREUSAGE_SAMPLER,
-        .width  = (Uint32)width,
-        .height = (Uint32)height,
-
-        .layer_count_or_depth = 1,
-        .num_levels = 1,
-
-        .props = properties,
-    };
-
-    SDL_GPUTexture *texture = SDL_CreateGPUTexture(device, &texture_info);
-    if (!texture) {
-        log_error("Failed to create gpu texture (%s).", SDL_GetError());
-        stbi_image_free(data);
-        return NULL;
-    }
-    if (properties) SDL_DestroyProperties(properties);
-
-    Uint32 upload_size = width * height * channels;
-    SDL_GPUTransferBufferCreateInfo transfer_buffer_info = {
-        .usage = SDL_GPU_TRANSFERBUFFERUSAGE_UPLOAD,
-        .size  = upload_size,
-    };
-
-    SDL_GPUTransferBuffer *transfer_buffer = SDL_CreateGPUTransferBuffer(device, &transfer_buffer_info);
-    if (!transfer_buffer) {
-        log_error("Failed to create gpu transfer buffer (%s).", SDL_GetError());
-        SDL_ReleaseGPUTexture(device, texture);
-        stbi_image_free(data);
-        return NULL;
-    }
-
-    void *transfer_data = SDL_MapGPUTransferBuffer(device, transfer_buffer, false);
-    if (!transfer_data) {
-        log_error("Failed to map gpu transfer buffer (%s).", SDL_GetError());
-        SDL_ReleaseGPUTransferBuffer(device, transfer_buffer);
-        SDL_ReleaseGPUTexture(device, texture);
-        stbi_image_free(data);
-        return NULL;
-    }
-    memcpy(transfer_data, data, upload_size);
-    SDL_UnmapGPUTransferBuffer(device, transfer_buffer);
-    stbi_image_free(data);
-
-    SDL_GPUTextureTransferInfo transfer_info = {
-        .transfer_buffer = transfer_buffer,
-        .pixels_per_row  = (Uint32)width,
-    };
-
-    SDL_GPUTextureRegion tetxure_region = {
-        .texture = texture,
-        .w = (Uint32)width,
-        .h = (Uint32)height,
-        .d = 1,
-    };
-
-    SDL_GPUCommandBuffer *command_buffer = SDL_AcquireGPUCommandBuffer(device);
-    if (!command_buffer) {
-        log_error("Failed to acquire gpu command buffer (%s).", SDL_GetError());
-        SDL_ReleaseGPUTransferBuffer(device, transfer_buffer);
-        SDL_ReleaseGPUTexture(device, texture);
-        return NULL;
-    }
-
-    SDL_GPUCopyPass *copy_pass = SDL_BeginGPUCopyPass(command_buffer);
-    SDL_UploadToGPUTexture(copy_pass, &transfer_info, &tetxure_region, false);
-    SDL_EndGPUCopyPass(copy_pass);
-
-    if (!SDL_SubmitGPUCommandBuffer(command_buffer)) {
-        log_error("Failed to submit gpu command buffer (%s).", SDL_GetError());
-        SDL_ReleaseGPUTransferBuffer(device, transfer_buffer);
-        SDL_ReleaseGPUTexture(device, texture);
-        SDL_CancelGPUCommandBuffer(command_buffer);
-        return NULL;
-    }
-
-    SDL_ReleaseGPUTransferBuffer(device, transfer_buffer);
-    return texture;
-}
-
 static SDL_GPUTexture *create_shader_texture(const char *name, const char *data, int width, int height, int channels) {
     SDL_GPUTextureFormat format = SDL_GPU_TEXTUREFORMAT_INVALID;
     if (channels == 1) format = SDL_GPU_TEXTUREFORMAT_A8_UNORM;
@@ -509,65 +405,87 @@ static SDL_GPUTexture *create_shader_texture(const char *name, const char *data,
     }
     if (properties) SDL_DestroyProperties(properties);
 
-    Uint32 upload_size = width * height * channels;
-    SDL_GPUTransferBufferCreateInfo transfer_buffer_info = {
-        .usage = SDL_GPU_TRANSFERBUFFERUSAGE_UPLOAD,
-        .size  = upload_size,
-    };
+    if (data) {
+        Uint32 upload_size = width * height * channels;
+        SDL_GPUTransferBufferCreateInfo transfer_buffer_info = {
+            .usage = SDL_GPU_TRANSFERBUFFERUSAGE_UPLOAD,
+            .size  = upload_size,
+        };
 
-    SDL_GPUTransferBuffer *transfer_buffer = SDL_CreateGPUTransferBuffer(device, &transfer_buffer_info);
-    if (!transfer_buffer) {
-        log_error("Failed to create gpu transfer buffer (%s).", SDL_GetError());
-        SDL_ReleaseGPUTexture(device, texture);
-        return NULL;
-    }
+        SDL_GPUTransferBuffer *transfer_buffer = SDL_CreateGPUTransferBuffer(device, &transfer_buffer_info);
+        if (!transfer_buffer) {
+            log_error("Failed to create gpu transfer buffer (%s).", SDL_GetError());
+            SDL_ReleaseGPUTexture(device, texture);
+            return NULL;
+        }
+
+        void *transfer_data = SDL_MapGPUTransferBuffer(device, transfer_buffer, false);
+        if (!transfer_data) {
+            log_error("Failed to map gpu transfer buffer (%s).", SDL_GetError());
+            SDL_ReleaseGPUTransferBuffer(device, transfer_buffer);
+            SDL_ReleaseGPUTexture(device, texture);
+            return NULL;
+        }
+        memcpy(transfer_data, data, upload_size);
+        SDL_UnmapGPUTransferBuffer(device, transfer_buffer);
+
+        SDL_GPUTextureTransferInfo transfer_info = {
+            .transfer_buffer = transfer_buffer,
+            .pixels_per_row  = (Uint32)width,
+        };
+
+        SDL_GPUTextureRegion tetxure_region = {
+            .texture = texture,
+            .w = (Uint32)width,
+            .h = (Uint32)height,
+            .d = 1,
+        };
+
+        SDL_GPUCommandBuffer *command_buffer = SDL_AcquireGPUCommandBuffer(device);
+        if (!command_buffer) {
+            log_error("Failed to acquire gpu command buffer (%s).", SDL_GetError());
+            SDL_ReleaseGPUTransferBuffer(device, transfer_buffer);
+            SDL_ReleaseGPUTexture(device, texture);
+            return NULL;
+        }
+
+        SDL_GPUCopyPass *copy_pass = SDL_BeginGPUCopyPass(command_buffer);
+        SDL_UploadToGPUTexture(copy_pass, &transfer_info, &tetxure_region, false);
+        SDL_EndGPUCopyPass(copy_pass);
+
+        if (!SDL_SubmitGPUCommandBuffer(command_buffer)) {
+            log_error("Failed to submit gpu command buffer (%s).", SDL_GetError());
+            SDL_ReleaseGPUTransferBuffer(device, transfer_buffer);
+            SDL_ReleaseGPUTexture(device, texture);
+            SDL_CancelGPUCommandBuffer(command_buffer);
+            return NULL;
+        }
 
-    void *transfer_data = SDL_MapGPUTransferBuffer(device, transfer_buffer, false);
-    if (!transfer_data) {
-        log_error("Failed to map gpu transfer buffer (%s).", SDL_GetError());
         SDL_ReleaseGPUTransferBuffer(device, transfer_buffer);
-        SDL_ReleaseGPUTexture(device, texture);
-        return NULL;
-    }
-    memcpy(transfer_data, data, upload_size);
-    SDL_UnmapGPUTransferBuffer(device, transfer_buffer);
-
-    SDL_GPUTextureTransferInfo transfer_info = {
-        .transfer_buffer = transfer_buffer,
-        .pixels_per_row  = (Uint32)width,
-    };
-
-    SDL_GPUTextureRegion tetxure_region = {
-        .texture = texture,
-        .w = (Uint32)width,
-        .h = (Uint32)height,
-        .d = 1,
-    };
-
-    SDL_GPUCommandBuffer *command_buffer = SDL_AcquireGPUCommandBuffer(device);
-    if (!command_buffer) {
-        log_error("Failed to acquire gpu command buffer (%s).", SDL_GetError());
-        SDL_ReleaseGPUTransferBuffer(device, transfer_buffer);
-        SDL_ReleaseGPUTexture(device, texture);
-        return NULL;
     }
 
-    SDL_GPUCopyPass *copy_pass = SDL_BeginGPUCopyPass(command_buffer);
-    SDL_UploadToGPUTexture(copy_pass, &transfer_info, &tetxure_region, false);
-    SDL_EndGPUCopyPass(copy_pass);
-
-    if (!SDL_SubmitGPUCommandBuffer(command_buffer)) {
-        log_error("Failed to submit gpu command buffer (%s).", SDL_GetError());
-        SDL_ReleaseGPUTransferBuffer(device, transfer_buffer);
-        SDL_ReleaseGPUTexture(device, texture);
-        SDL_CancelGPUCommandBuffer(command_buffer);
-        return NULL;
-    }
-
-    SDL_ReleaseGPUTransferBuffer(device, transfer_buffer);
     return texture;
 }
 
+static SDL_GPUTexture *create_shader_texture(const char *path) {
+    int width = 0, height = 0, channels = 0; 
+    stbi_uc *data = stbi_load(path, &width, &height, &channels, 0);
+    if (!data) {
+        log_error("Failed to load texture (\"%s\").", path);
+        return NULL;
+    }
+
+    SDL_GPUTexture *result = create_shader_texture(path, (char *)data, width, height, channels);
+    if (!result) {
+        log_error("Failed to load texture (\"%s\").", path);
+        stbi_image_free(data);
+        return NULL;
+    }
+    stbi_image_free(data);
+
+    return result;
+}
+
 static void blit(char *dst, Sint32 dst_pitch, Sint32 dst_x, Sint32 dst_y, char *src, Sint32 src_pitch, Sint32 width, Sint32 height, int components = 4) {
     for (Sint32 y = 0; y < height; y++)
         memmove(&dst[((dst_y + y) * dst_pitch + dst_x) * components], &src[y * src_pitch * components], width * components);