add tomato image generator helper functions (untested)

src/CMakeLists.txt

@@ -13,6 +13,9 @@ target_sources(tomato PUBLIC
 	./main.cpp
 	./icon.rc
 
+	./icon_generator.hpp
+	./icon_generator.cpp
+
 	./sys_check.hpp
 	./sys_check.cpp
 

src/icon_generator.cpp

@@ -0,0 +1,62 @@
+#include "./icon_generator.hpp"
+
+#include <qoi/qoi.h>
+#include <cstdlib>
+
+namespace {
+#include "../res/icon/tomato_v1_256.qoi.h"
+}
+
+namespace IconGenerator {
+
+SDL_Surface* base(void) {
+	//ImageLoaderQOI{}.loadFromMemoryRGBA(tomato_v1_256_qoi, tomato_v1_256_qoi_len);
+
+	qoi_desc desc;
+
+	uint8_t* img_data = static_cast<uint8_t*>(
+		qoi_decode(tomato_v1_256_qoi, tomato_v1_256_qoi_len, &desc, 4)
+	);
+	if (img_data == nullptr) {
+		// not readable
+		return {};
+	}
+
+	auto* surf = SDL_CreateSurfaceFrom(desc.width, desc.height, SDL_PIXELFORMAT_RGBA32, img_data, 0);
+	if (surf == nullptr) {
+		return {}; // ??
+	}
+
+	auto* surf_dup = SDL_DuplicateSurface(surf);
+
+	SDL_DestroySurface(surf);
+
+	free(img_data);
+
+	return surf_dup;
+}
+
+SDL_Surface* colorIndicator(float r, float g, float b, float a) {
+	auto* surf = base();
+	if (surf == nullptr) {
+		return nullptr;
+	}
+
+	const SDL_Rect rect {
+		// TODO: gaps and smaller
+		// lower right quarter
+		surf->w/2,
+		surf->h/2,
+		surf->w/2,
+		surf->h/2,
+	};
+
+	const auto color = SDL_MapSurfaceRGBA(surf, r*255, g*255, b*255, a*255);
+
+	SDL_FillSurfaceRect(surf, &rect, color);
+
+	return surf;
+}
+
+} // IconGenerator
+

src/icon_generator.hpp

@@ -0,0 +1,18 @@
+#pragma once
+
+#include <SDL3/SDL.h>
+
+#include <memory>
+
+namespace IconGenerator {
+
+// remember to SDL_DestroySurface()
+
+// tomato icon
+SDL_Surface* base(void);
+
+// tomato icon with colored indicator
+SDL_Surface* colorIndicator(float r, float g, float b, float a);
+
+} // IconGenerator
+