Slate/src/components/Sprite.cpp

#include <format>

#include "SDL3/SDL_pixels.h"
#include "Sprite.hpp"
#include "physfs.h"

#define STB_IMAGE_IMPLEMENTATION
#include "../stb_image.h"

namespace Slate {
    Sprite Sprite::FromFile(SDL_Renderer *renderer, std::string path) {
        Sprite sprite{};
        SDL_Surface *surface = nullptr;

        if (!PHYSFS_exists(path.c_str())) {
            throw std::runtime_error(std::format("File not found: {}", path));
        }
        PHYSFS_file *file = PHYSFS_openRead(path.c_str());
        const PHYSFS_sint64 length = PHYSFS_fileLength(file);
        auto *buffer = new unsigned char[length];
        PHYSFS_readBytes(file, buffer, length);
        PHYSFS_close(file);

        int width, height, channels;
        unsigned char *image = stbi_load_from_memory(
            buffer, static_cast<int>(length),
            &width, &height, &channels, 4
        );
        if (!image) {
            delete[] buffer;
            throw std::runtime_error(std::format("Failed to parse image: {}", path));
        }

        surface = SDL_CreateSurfaceFrom(width, height, SDL_PIXELFORMAT_ABGR8888, image, width * channels);
        if (surface == nullptr) {
            throw std::runtime_error(std::format("Unable to load spritesheet file: {}", path));
        }

        sprite.texture = SDL_CreateTextureFromSurface(renderer, surface);
        sprite.rect.w = static_cast<float>(sprite.texture->w);
        sprite.rect.h = static_cast<float>(sprite.texture->h);
        sprite.rect.x = sprite.rect.y = 0;

        SDL_SetTextureScaleMode(sprite.texture, SDL_SCALEMODE_NEAREST);
        SDL_DestroySurface(surface);
        return sprite;
    }

    Sprite Sprite::FromXML(SDL_Renderer *renderer, tinyxml2::XMLElement *element) {
        const char *path;
        element->QueryStringAttribute("texture", &path);
        Sprite sprite = FromFile(renderer, path);
        const auto *rect = element->FirstChildElement();
        rect->QueryFloatAttribute("x", &sprite.rect.x);
        rect->QueryFloatAttribute("y", &sprite.rect.y);
        rect->QueryFloatAttribute("w", &sprite.rect.w);
        rect->QueryFloatAttribute("h", &sprite.rect.h);
        return sprite;
    }
}