Fixed getTextureData() when failed to load texture

getTextureData() created an image based on width and height values that are undefined if image failed to load.

Replaced with default image and image is constructed only if successfully loaded.

src/core/helpers.cpp

@@ -49,11 +49,16 @@ getTextureData(std::string const& filename, u32& width, u32& height, bool flip)
 	auto const path = config::resources_path(filename);
 	auto const channels_nb = 4u;
 	unsigned char* image_data = stbi_load(path.c_str(), reinterpret_cast<int*>(&width), reinterpret_cast<int*>(&height), nullptr, channels_nb);
-	std::vector<unsigned char> image(width * height * channels_nb);
 	if (image_data == nullptr) {
 		LogWarning("Couldn't load or decode image file %s", path.c_str());
-		return image;
+
+		// Provide a small empty image instead in case of failure.
+		width = 16;
+		height = 16;
+		return std::vector<unsigned char>(width * height * channels_nb);
 	}
+
+	std::vector<unsigned char> image(width * height * channels_nb);
 	if (!flip) {
 		std::memcpy(image.data(), image_data, image.size());
 		stbi_image_free(image_data);