Image: Add static `is_format_compressed` function.

core/io/image.cpp

@@ -521,7 +521,7 @@ void Image::convert(Format p_new_format) {
 	// Includes the main image.
 	const int mipmap_count = get_mipmap_count() + 1;
 
-	if (format > FORMAT_RGBE9995 || p_new_format > FORMAT_RGBE9995) {
+	if (Image::is_format_compressed(format) || Image::is_format_compressed(p_new_format)) {
 		ERR_FAIL_MSG("Cannot convert to <-> from compressed formats. Use compress() and decompress() instead.");
 
 	} else if (format > FORMAT_RGBA8 || p_new_format > FORMAT_RGBA8) {
@@ -1662,7 +1662,7 @@ int Image::_get_dst_image_size(int p_width, int p_height, Format p_format, int &
 }
 
 bool Image::_can_modify(Format p_format) const {
-	return p_format <= FORMAT_RGBE9995;
+	return !Image::is_format_compressed(p_format);
 }
 
 template <class Component, int CC, bool renormalize,
@@ -2616,7 +2616,11 @@ int Image::get_image_mipmap_offset_and_dimensions(int p_width, int p_height, For
 }
 
 bool Image::is_compressed() const {
-	return format > FORMAT_RGBE9995;
+	return is_format_compressed(format);
+}
+
+bool Image::is_format_compressed(Format p_format) {
+	return p_format > FORMAT_RGBE9995;
 }
 
 Error Image::decompress() {

core/io/image.h

@@ -376,6 +376,7 @@ public:
 	Error compress_from_channels(CompressMode p_mode, UsedChannels p_channels, ASTCFormat p_astc_format = ASTC_FORMAT_4x4);
 	Error decompress();
 	bool is_compressed() const;
+	static bool is_format_compressed(Format p_format);
 
 	void fix_alpha_edges();
 	void premultiply_alpha();

modules/astcenc/image_compress_astcenc.cpp

@@ -41,7 +41,7 @@ void _compress_astc(Image *r_img, Image::ASTCFormat p_format) {
 	// TODO: See how to handle lossy quality.
 
 	Image::Format img_format = r_img->get_format();
-	if (img_format >= Image::FORMAT_DXT1) {
+	if (Image::is_format_compressed(img_format)) {
 		return; // Do not compress, already compressed.
 	}
 

modules/basis_universal/image_compress_basisu.cpp

@@ -243,7 +243,7 @@ Ref<Image> basis_universal_unpacker_ptr(const uint8_t *p_data, int p_size) {
 		basist::basisu_image_level_info basisu_level;
 		transcoder.get_image_level_info(src_ptr, src_size, basisu_level, 0, i);
 
-		uint32_t mip_block_or_pixel_count = image_format >= Image::FORMAT_DXT1 ? basisu_level.m_total_blocks : basisu_level.m_orig_width * basisu_level.m_orig_height;
+		uint32_t mip_block_or_pixel_count = Image::is_format_compressed(image_format) ? basisu_level.m_total_blocks : basisu_level.m_orig_width * basisu_level.m_orig_height;
 		int ofs = Image::get_image_mipmap_offset(basisu_info.m_width, basisu_info.m_height, image_format, i);
 
 		bool result = transcoder.transcode_image_level(src_ptr, src_size, 0, i, dst + ofs, mip_block_or_pixel_count, basisu_format);

modules/cvtt/image_compress_cvtt.cpp

@@ -142,7 +142,7 @@ static void _digest_job_queue(void *p_job_queue, uint32_t p_index) {
 }
 
 void image_compress_cvtt(Image *p_image, Image::UsedChannels p_channels) {
-	if (p_image->get_format() >= Image::FORMAT_BPTC_RGBA) {
+	if (p_image->is_compressed()) {
 		return; //do not compress, already compressed
 	}
 	int w = p_image->get_width();

modules/etcpak/image_compress_etcpak.cpp

@@ -92,7 +92,7 @@ void _compress_etcpak(EtcpakType p_compresstype, Image *r_img) {
 	uint64_t start_time = OS::get_singleton()->get_ticks_msec();
 
 	Image::Format img_format = r_img->get_format();
-	if (img_format >= Image::FORMAT_DXT1) {
+	if (Image::is_format_compressed(img_format)) {
 		return; // Do not compress, already compressed.
 	}
 	if (img_format > Image::FORMAT_RGBA8) {