From a3d193516c8adf4ff4e47330ceea4f97d8080a15 Mon Sep 17 00:00:00 2001
From: Green Sky <green@g-s.xyz>
Date: Fri, 8 Mar 2024 22:04:58 +0100
Subject: [PATCH] add updating to textures

---
 src/sdlrenderer_texture_uploader.cpp | 33 +++++++++++++++++++++++++++-
 src/sdlrenderer_texture_uploader.hpp |  3 ++-
 src/texture_uploader.hpp             | 15 +++++++++++--
 3 files changed, 47 insertions(+), 4 deletions(-)

diff --git a/src/sdlrenderer_texture_uploader.cpp b/src/sdlrenderer_texture_uploader.cpp
index da05832..267eec9 100644
--- a/src/sdlrenderer_texture_uploader.cpp
+++ b/src/sdlrenderer_texture_uploader.cpp
@@ -1,13 +1,15 @@
 #include "./sdlrenderer_texture_uploader.hpp"
 
 #include <cassert>
+#include <cstdint>
+#include <cstring>
 
 SDLRendererTextureUploader::SDLRendererTextureUploader(SDL_Renderer* renderer_) :
 	renderer(renderer_)
 {
 }
 
-uint64_t SDLRendererTextureUploader::uploadRGBA(const uint8_t* data, uint32_t width, uint32_t height, Filter filter) {
+uint64_t SDLRendererTextureUploader::uploadRGBA(const uint8_t* data, uint32_t width, uint32_t height, Filter filter, Access access) {
 	// TODO: test if pitch is 4 or 4*width
 	SDL_Surface* surf = SDL_CreateSurfaceFrom(
 		(void*)data,
@@ -17,6 +19,14 @@ uint64_t SDLRendererTextureUploader::uploadRGBA(const uint8_t* data, uint32_t wi
 	);
 	assert(surf); // TODO: add error reporting
 
+	// hacky hint usage
+	if (access == Access::STREAMING) {
+		SDL_SetHint("SDL_TextureAccess", "SDL_TEXTUREACCESS_STREAMING");
+	} else {
+		SDL_SetHint("SDL_TextureAccess", "SDL_TEXTUREACCESS_STATIC");
+	}
+	// TODO: cleanup hints after
+
 	SDL_Texture* tex = SDL_CreateTextureFromSurface(renderer, surf);
 	assert(tex); // TODO: add error reporting
 
@@ -31,6 +41,27 @@ uint64_t SDLRendererTextureUploader::uploadRGBA(const uint8_t* data, uint32_t wi
 	return reinterpret_cast<uint64_t>(tex);
 }
 
+bool SDLRendererTextureUploader::updateRGBA(uint64_t tex_id, const uint8_t* data, size_t size) {
+	auto* texture = static_cast<SDL_Texture*>(reinterpret_cast<void*>(tex_id));
+	if (texture == nullptr) {
+		return false;
+	}
+
+	uint8_t* pixels = nullptr;
+	int pitch = 0;
+
+	if (SDL_LockTexture(texture, nullptr, (void**)&pixels, &pitch) != 0) {
+		// TODO: error
+		return false;
+	}
+
+	std::memcpy(pixels, data, size);
+
+	SDL_UnlockTexture(texture);
+
+	return true;
+}
+
 void SDLRendererTextureUploader::destroy(uint64_t tex_id) {
 	SDL_DestroyTexture(static_cast<SDL_Texture*>(reinterpret_cast<void*>(tex_id)));
 }
diff --git a/src/sdlrenderer_texture_uploader.hpp b/src/sdlrenderer_texture_uploader.hpp
index 64bc390..6e028d0 100644
--- a/src/sdlrenderer_texture_uploader.hpp
+++ b/src/sdlrenderer_texture_uploader.hpp
@@ -10,7 +10,8 @@ struct SDLRendererTextureUploader : public TextureUploaderI {
 	SDLRendererTextureUploader(SDL_Renderer* renderer_);
 	~SDLRendererTextureUploader(void) = default;
 
-	uint64_t uploadRGBA(const uint8_t* data, uint32_t width, uint32_t height, Filter filter) override;
+	uint64_t uploadRGBA(const uint8_t* data, uint32_t width, uint32_t height, Filter filter, Access access) override;
+	bool updateRGBA(uint64_t tex_id, const uint8_t* data, size_t size) override;
 	void destroy(uint64_t tex_id) override;
 };
 
diff --git a/src/texture_uploader.hpp b/src/texture_uploader.hpp
index 3fcc024..1c6668c 100644
--- a/src/texture_uploader.hpp
+++ b/src/texture_uploader.hpp
@@ -1,18 +1,29 @@
 #pragma once
 
 #include <cstdint>
+#include <cstddef>
 
 struct TextureUploaderI {
-	static constexpr const char* version {"1"};
+	static constexpr const char* version {"2"};
 
 	enum Filter {
 		NEAREST,
 		LINEAR,
 	};
 
+	enum Access {
+		STATIC,
+		STREAMING,
+		// target?
+	};
+
 	virtual ~TextureUploaderI(void) {}
 
-	virtual uint64_t uploadRGBA(const uint8_t* data, uint32_t width, uint32_t height, Filter filter = LINEAR) = 0;
+	virtual uint64_t uploadRGBA(const uint8_t* data, uint32_t width, uint32_t height, Filter filter = LINEAR, Access access = STATIC) = 0;
+
+	// keeps width height filter
+	// TODO: wh instead of size?
+	virtual bool updateRGBA(uint64_t tex_id, const uint8_t* data, size_t size) = 0;
 
 	virtual void destroy(uint64_t tex_id) = 0;
 };