Add image previews for 3D and layered textures

editor/plugins/editor_preview_plugins.cpp

@@ -76,7 +76,7 @@ void post_process_preview(Ref<Image> p_image) {
 }
 
 bool EditorTexturePreviewPlugin::handles(const String &p_type) const {
-	return ClassDB::is_parent_class(p_type, "Texture2D");
+	return ClassDB::is_parent_class(p_type, "Texture2D") || ClassDB::is_parent_class(p_type, "Texture3D") || ClassDB::is_parent_class(p_type, "TextureLayered");
 }
 
 bool EditorTexturePreviewPlugin::generate_small_preview_automatically() const {
@@ -85,9 +85,13 @@ bool EditorTexturePreviewPlugin::generate_small_preview_automatically() const {
 
 Ref<Texture2D> EditorTexturePreviewPlugin::generate(const Ref<Resource> &p_from, const Size2 &p_size, Dictionary &p_metadata) const {
 	Ref<Image> img;
-	Ref<AtlasTexture> atex = p_from;
-	if (atex.is_valid()) {
-		Ref<Texture2D> tex = atex->get_atlas();
+
+	Ref<AtlasTexture> tex_atlas = p_from;
+	Ref<Texture3D> tex_3d = p_from;
+	Ref<TextureLayered> tex_lyr = p_from;
+
+	if (tex_atlas.is_valid()) {
+		Ref<Texture2D> tex = tex_atlas->get_atlas();
 		if (!tex.is_valid()) {
 			return Ref<Texture2D>();
 		}
@@ -97,11 +101,36 @@ Ref<Texture2D> EditorTexturePreviewPlugin::generate(const Ref<Resource> &p_from,
 			return Ref<Texture2D>();
 		}
 
-		if (!atex->get_region().has_area()) {
+		if (!tex_atlas->get_region().has_area()) {
+			return Ref<Texture2D>();
+		}
+
+		img = atlas->get_region(tex_atlas->get_region());
+
+	} else if (tex_3d.is_valid()) {
+		if (tex_3d->get_depth() == 0) {
+			return Ref<Texture2D>();
+		}
+
+		const int mid_depth = (tex_3d->get_depth() - 1) / 2;
+
+		Vector<Ref<Image>> data = tex_3d->get_data();
+		if (!data.is_empty() && data[mid_depth].is_valid()) {
+			img = data[mid_depth]->duplicate();
+		}
+
+	} else if (tex_lyr.is_valid()) {
+		if (tex_lyr->get_layers() == 0) {
 			return Ref<Texture2D>();
 		}
 
-		img = atlas->get_region(atex->get_region());
+		const int mid_layer = (tex_lyr->get_layers() - 1) / 2;
+
+		Ref<Image> data = tex_lyr->get_layer_data(mid_layer);
+		if (data.is_valid()) {
+			img = data->duplicate();
+		}
+
 	} else {
 		Ref<Texture2D> tex = p_from;
 		if (tex.is_valid()) {
@@ -115,6 +144,7 @@ Ref<Texture2D> EditorTexturePreviewPlugin::generate(const Ref<Resource> &p_from,
 	if (img.is_null() || img->is_empty()) {
 		return Ref<Texture2D>();
 	}
+
 	p_metadata["dimensions"] = img->get_size();
 
 	img->clear_mipmaps();