-Fix freezes caused by etccomp2, closes #9183

-Normalmaps are now detected and imported as RGTC, both in S3TC and ETC2, this improves their quality.

3 files changed, 33 insertions, 10 deletions

diff --git a/modules/etc/image_etc.cpp b/modules/etc/image_etc.cpp
index 4ccd5c8d89..948f50b782 100644
--- a/modules/etc/image_etc.cpp
+++ b/modules/etc/image_etc.cpp
@@ -94,10 +94,20 @@ static void _decompress_etc2(Image *p_img) {
 	// not implemented, to be removed
 }
 
-static void _compress_etc(Image *p_img, float p_lossy_quality, bool force_etc1_format) {
+static void _compress_etc(Image *p_img, float p_lossy_quality, bool force_etc1_format, Image::CompressSource p_source) {
 	Image::Format img_format = p_img->get_format();
 	Image::DetectChannels detected_channels = p_img->get_detected_channels();
 
+	if (p_source == Image::COMPRESS_SOURCE_SRGB && (detected_channels == Image::DETECTED_R || detected_channels == Image::DETECTED_RG)) {
+		//R and RG do not support SRGB
+		detected_channels = Image::DETECTED_RGB;
+	}
+
+	if (p_source == Image::COMPRESS_SOURCE_NORMAL) {
+		//use RG channels only for normal
+		detected_channels = Image::DETECTED_RG;
+	}
+
 	if (img_format >= Image::FORMAT_DXT1) {
 		return; //do not compress, already compressed
 	}
@@ -128,10 +138,18 @@ static void _compress_etc(Image *p_img, float p_lossy_quality, bool force_etc1_f
 	PoolVector<uint8_t>::Write w = dst_data.write();
 
 	// prepare parameters to be passed to etc2comp
-	int num_cpus = OS::get_singleton()->get_processor_count();
+	int num_cpus = OS::get_singleton()->get_processor_count() * 2; //generally some cpus have 2 threads
 	int encoding_time = 0;
-	float effort = CLAMP(p_lossy_quality * 100, 0, 100);
-	Etc::ErrorMetric error_metric = Etc::ErrorMetric::BT709; // NOTE: we can experiment with other error metrics
+	float effort = 0.0; //default, reasonable time
+
+	if (p_lossy_quality > 0.75)
+		effort = 0.4;
+	else if (p_lossy_quality > 0.85)
+		effort = 0.6;
+	else if (p_lossy_quality > 0.95)
+		effort = 0.8;
+
+	Etc::ErrorMetric error_metric = Etc::ErrorMetric::RGBX; // NOTE: we can experiment with other error metrics
 	Etc::Image::Format etc2comp_etc_format = _image_format_to_etc2comp_format(etc_format);
 
 	int wofs = 0;
@@ -164,11 +182,11 @@ static void _compress_etc(Image *p_img, float p_lossy_quality, bool force_etc1_f
 }
 
 static void _compress_etc1(Image *p_img, float p_lossy_quality) {
-	_compress_etc(p_img, p_lossy_quality, true);
+	_compress_etc(p_img, p_lossy_quality, true, Image::COMPRESS_SOURCE_GENERIC);
 }
 
-static void _compress_etc2(Image *p_img, float p_lossy_quality) {
-	_compress_etc(p_img, p_lossy_quality, false);
+static void _compress_etc2(Image *p_img, float p_lossy_quality, Image::CompressSource p_source) {
+	_compress_etc(p_img, p_lossy_quality, false, p_source);
 }
 
 void _register_etc_compress_func() {
diff --git a/modules/squish/image_compress_squish.cpp b/modules/squish/image_compress_squish.cpp
index 32772e0cd2..efce76c805 100644
--- a/modules/squish/image_compress_squish.cpp
+++ b/modules/squish/image_compress_squish.cpp
@@ -80,7 +80,7 @@ void image_decompress_squish(Image *p_image) {
 	p_image->create(p_image->get_width(), p_image->get_height(), p_image->has_mipmaps(), target_format, data);
 }
 
-void image_compress_squish(Image *p_image, bool p_srgb) {
+void image_compress_squish(Image *p_image, Image::CompressSource p_source) {
 
 	if (p_image->get_format() >= Image::FORMAT_DXT1)
 		return; //do not compress, already compressed
@@ -97,11 +97,16 @@ void image_compress_squish(Image *p_image, bool p_srgb) {
 
 		p_image->convert(Image::FORMAT_RGBA8); //still uses RGBA to convert
 
-		if (p_srgb && (dc == Image::DETECTED_R || dc == Image::DETECTED_RG)) {
+		if (p_source == Image::COMPRESS_SOURCE_SRGB && (dc == Image::DETECTED_R || dc == Image::DETECTED_RG)) {
 			//R and RG do not support SRGB
 			dc = Image::DETECTED_RGB;
 		}
 
+		if (p_source == Image::COMPRESS_SOURCE_NORMAL) {
+			//R and RG do not support SRGB
+			dc = Image::DETECTED_RG;
+		}
+
 		switch (dc) {
 			case Image::DETECTED_L: {
 
diff --git a/modules/squish/image_compress_squish.h b/modules/squish/image_compress_squish.h
index 8d859b8e0b..68aaeefc30 100644
--- a/modules/squish/image_compress_squish.h
+++ b/modules/squish/image_compress_squish.h
@@ -32,7 +32,7 @@
 
 #include "image.h"
 
-void image_compress_squish(Image *p_image, bool p_srgb);
+void image_compress_squish(Image *p_image, Image::CompressSource p_source);
 void image_decompress_squish(Image *p_image);
 
 #endif // IMAGE_COMPRESS_SQUISH_H