Implement color conversion for dark SVG icons

2 files changed, 52 insertions, 6 deletions

diff --git a/modules/svg/image_loader_svg.cpp b/modules/svg/image_loader_svg.cpp
index 086cc202f9..f5c379d32e 100644
--- a/modules/svg/image_loader_svg.cpp
+++ b/modules/svg/image_loader_svg.cpp
@@ -47,7 +47,49 @@ SVGRasterizer::~SVGRasterizer() {
 
 SVGRasterizer ImageLoaderSVG::rasterizer;
 
-Error ImageLoaderSVG::_create_image(Ref<Image> p_image, const PoolVector<uint8_t> *p_data, float p_scale, bool upsample) {
+inline void change_nsvg_paint_color(NSVGpaint *p_paint, const uint32_t p_old, const uint32_t p_new) {
+
+	if (p_paint->type == NSVG_PAINT_COLOR) {
+		if (p_paint->color << 8 == p_old << 8) {
+			p_paint->color = p_new;
+		}
+	}
+
+	if (p_paint->type == NSVG_PAINT_LINEAR_GRADIENT || p_paint->type == NSVG_PAINT_RADIAL_GRADIENT) {
+		for (int stop_index = 0; stop_index < p_paint->gradient->nstops; stop_index++) {
+			if (p_paint->gradient->stops[stop_index].color << 8 == p_old << 8) {
+				p_paint->gradient->stops[stop_index].color = p_new;
+			}
+		}
+	}
+}
+void ImageLoaderSVG::_convert_colors(NSVGimage *p_svg_image, const Dictionary p_colors) {
+	List<uint32_t> replace_colors_i;
+	List<uint32_t> new_colors_i;
+	List<Color> replace_colors;
+	List<Color> new_colors;
+
+	for (int i = 0; i < p_colors.keys().size(); i++) {
+		Variant r_c = p_colors.keys()[i];
+		Variant n_c = p_colors[p_colors.keys()[i]];
+		if (r_c.get_type() == Variant::COLOR && n_c.get_type() == Variant::COLOR) {
+			Color replace_color = r_c;
+			Color new_color = n_c;
+			replace_colors_i.push_back(replace_color.to_ABGR32());
+			new_colors_i.push_back(new_color.to_ABGR32());
+		}
+	}
+
+	for (NSVGshape *shape = p_svg_image->shapes; shape != NULL; shape = shape->next) {
+
+		for (int i = 0; i < replace_colors_i.size(); i++) {
+			change_nsvg_paint_color(&(shape->stroke), replace_colors_i[i], new_colors_i[i]);
+			change_nsvg_paint_color(&(shape->fill), replace_colors_i[i], new_colors_i[i]);
+		}
+	}
+}
+
+Error ImageLoaderSVG::_create_image(Ref<Image> p_image, const PoolVector<uint8_t> *p_data, float p_scale, bool upsample, const Dictionary *p_replace_colors) {
 	NSVGimage *svg_image;
 	PoolVector<uint8_t>::Read src_r = p_data->read();
 	svg_image = nsvgParse((char *)src_r.ptr(), "px", 96);
@@ -56,6 +98,9 @@ Error ImageLoaderSVG::_create_image(Ref<Image> p_image, const PoolVector<uint8_t
 		return ERR_FILE_CORRUPT;
 	}
 
+	if (p_replace_colors != NULL) {
+		_convert_colors(svg_image, *p_replace_colors);
+	}
 	float upscale = upsample ? 2.0 : 1.0;
 
 	int w = (int)(svg_image->width * p_scale * upscale);
@@ -78,7 +123,7 @@ Error ImageLoaderSVG::_create_image(Ref<Image> p_image, const PoolVector<uint8_t
 	return OK;
 }
 
-Error ImageLoaderSVG::create_image_from_string(Ref<Image> p_image, const char *svg_str, float p_scale, bool upsample) {
+Error ImageLoaderSVG::create_image_from_string(Ref<Image> p_image, const char *svg_str, float p_scale, bool upsample, const Dictionary *p_replace_colors) {
 
 	size_t str_len = strlen(svg_str);
 	PoolVector<uint8_t> src_data;
@@ -86,7 +131,7 @@ Error ImageLoaderSVG::create_image_from_string(Ref<Image> p_image, const char *s
 	PoolVector<uint8_t>::Write src_w = src_data.write();
 	memcpy(src_w.ptr(), svg_str, str_len + 1);
 
-	return _create_image(p_image, &src_data, p_scale, upsample);
+	return _create_image(p_image, &src_data, p_scale, upsample, p_replace_colors);
 }
 
 Error ImageLoaderSVG::load_image(Ref<Image> p_image, FileAccess *f, bool p_force_linear, float p_scale) {
diff --git a/modules/svg/image_loader_svg.h b/modules/svg/image_loader_svg.h
index 1f2ec3c1c2..f692b1b28c 100644
--- a/modules/svg/image_loader_svg.h
+++ b/modules/svg/image_loader_svg.h
@@ -54,14 +54,15 @@ public:
 class ImageLoaderSVG : public ImageFormatLoader {
 
 	static SVGRasterizer rasterizer;
-	static Error _create_image(Ref<Image> p_image, const PoolVector<uint8_t> *p_data, float p_scale, bool upsample);
+	static void _convert_colors(NSVGimage *p_svg_imge, const Dictionary p_colors);
+	static Error _create_image(Ref<Image> p_image, const PoolVector<uint8_t> *p_data, float p_scale, bool upsample, const Dictionary *p_replace_color = NULL);
 
 public:
-	static Error create_image_from_string(Ref<Image> p_image, const char *p_svg_str, float p_scale, bool upsample);
+	static Error create_image_from_string(Ref<Image> p_image, const char *p_svg_str, float p_scale, bool upsample, const Dictionary *p_replace_color = NULL);
 
 	virtual Error load_image(Ref<Image> p_image, FileAccess *f, bool p_force_linear, float p_scale);
 	virtual void get_recognized_extensions(List<String> *p_extensions) const;
 	ImageLoaderSVG();
 };
 
-#endif
\ No newline at end of file
+#endif