- Allowed projector texture in directional light

- Added projector scale / offset in directional light
- Added directional light matrix, scale and offset in forward shaders
- Added computation logic of the projection in the forward and forward mobile shaders
- Computing projector matrix in the update_light_buffers and pushing it to the gpu
- Adapted light models to have projector scale and offset stored (even in gles3 for the future inclusion of projectors)
- Added a sub group for the directional light projector properties
- Added directional projector pipeline specialization constant for mobile and forward rendering

TODO:
- Find a way to hide the delimitation of the projector texture repetition when using mimap or linear projector filtering due the use of an atlas

Author: TheMagnat

drivers/gles3/storage/light_storage.cpp

@@ -181,18 +181,30 @@ void LightStorage::light_set_projector(RID p_light, RID p_texture) {
 		return;
 	}
 
-	if (light->type != RS::LIGHT_DIRECTIONAL && light->projector.is_valid()) {
+	if (light->projector.is_valid()) {
 		texture_storage->texture_remove_from_decal_atlas(light->projector, light->type == RS::LIGHT_OMNI);
 	}
 
 	light->projector = p_texture;
 
-	if (light->type != RS::LIGHT_DIRECTIONAL) {
-		if (light->projector.is_valid()) {
-			texture_storage->texture_add_to_decal_atlas(light->projector, light->type == RS::LIGHT_OMNI);
-		}
-		light->dependency.changed_notify(Dependency::DEPENDENCY_CHANGED_LIGHT_SOFT_SHADOW_AND_PROJECTOR);
+	if (light->projector.is_valid()) {
+		texture_storage->texture_add_to_decal_atlas(light->projector, light->type == RS::LIGHT_OMNI);
 	}
+	light->dependency.changed_notify(Dependency::DEPENDENCY_CHANGED_LIGHT_SOFT_SHADOW_AND_PROJECTOR);
+}
+
+void LightStorage::light_set_projector_scale(RID p_light, const Vector2 &p_scale) {
+	Light *light = light_owner.get_or_null(p_light);
+	ERR_FAIL_NULL(light);
+
+	light->projector_scale = p_scale;
+}
+
+void LightStorage::light_set_projector_offset(RID p_light, const Vector2 &p_offset) {
+	Light *light = light_owner.get_or_null(p_light);
+	ERR_FAIL_NULL(light);
+
+	light->projector_offset = p_offset;
 }
 
 void LightStorage::light_set_negative(RID p_light, bool p_enable) {

drivers/gles3/storage/light_storage.h

@@ -50,6 +50,8 @@ struct Light {
 	float param[RS::LIGHT_PARAM_MAX];
 	Color color = Color(1, 1, 1, 1);
 	RID projector;
+	Vector2 projector_scale;
+	Vector2 projector_offset;
 	bool shadow = false;
 	bool negative = false;
 	bool reverse_cull = false;
@@ -322,6 +324,8 @@ class LightStorage : public RendererLightStorage {
 	virtual void light_set_param(RID p_light, RS::LightParam p_param, float p_value) override;
 	virtual void light_set_shadow(RID p_light, bool p_enabled) override;
 	virtual void light_set_projector(RID p_light, RID p_texture) override;
+	virtual void light_set_projector_scale(RID p_light, const Vector2 &p_scale) override;
+	virtual void light_set_projector_offset(RID p_light, const Vector2 &p_offset) override;
 	virtual void light_set_negative(RID p_light, bool p_enable) override;
 	virtual void light_set_cull_mask(RID p_light, uint32_t p_mask) override;
 	virtual void light_set_distance_fade(RID p_light, bool p_enabled, float p_begin, float p_shadow, float p_length) override;

scene/3d/light_3d.cpp

@@ -222,6 +222,24 @@ Ref<Texture2D> Light3D::get_projector() const {
 	return projector;
 }
 
+void Light3D::set_projector_scale(const Vector2 &p_scale) {
+	projector_scale = p_scale;
+	RS::get_singleton()->light_set_projector_scale(light, p_scale);
+}
+
+Vector2 Light3D::get_projector_scale() const {
+	return projector_scale;
+}
+
+void Light3D::set_projector_offset(const Vector2 &p_offset) {
+	projector_offset = p_offset;
+	RS::get_singleton()->light_set_projector_offset(light, p_offset);
+}
+
+Vector2 Light3D::get_projector_offset() const {
+	return projector_offset;
+}
+
 void Light3D::owner_changed_notify() {
 	// For cases where owner changes _after_ entering tree (as example, editor editing).
 	_update_visibility();
@@ -327,8 +345,8 @@ void Light3D::_validate_property(PropertyInfo &p_property) const {
 		p_property.usage = PROPERTY_USAGE_NO_EDITOR;
 	}
 
-	if (get_light_type() != RS::LIGHT_DIRECTIONAL && (p_property.name == "light_angular_distance" || p_property.name == "light_intensity_lux")) {
-		// Angular distance and Light Intensity Lux are only used in DirectionalLight3D.
+	if (get_light_type() != RS::LIGHT_DIRECTIONAL && (p_property.name == "light_angular_distance" || p_property.name == "light_intensity_lux" || p_property.name == "Projector" || p_property.name == "light_projector_scale" || p_property.name == "light_projector_offset")) {
+		// Angular distance, Light Intensity Lux and Projector Subgroup/Scale/Offset are only used in DirectionalLight3D.
 		p_property.usage = PROPERTY_USAGE_NONE;
 	} else if (get_light_type() == RS::LIGHT_DIRECTIONAL && p_property.name == "light_intensity_lumens") {
 		p_property.usage = PROPERTY_USAGE_NONE;
@@ -386,6 +404,12 @@ void Light3D::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("set_projector", "projector"), &Light3D::set_projector);
 	ClassDB::bind_method(D_METHOD("get_projector"), &Light3D::get_projector);
 
+	ClassDB::bind_method(D_METHOD("set_projector_scale", "scale"), &Light3D::set_projector_scale);
+	ClassDB::bind_method(D_METHOD("get_projector_scale"), &Light3D::get_projector_scale);
+
+	ClassDB::bind_method(D_METHOD("set_projector_offset", "offset"), &Light3D::set_projector_offset);
+	ClassDB::bind_method(D_METHOD("get_projector_offset"), &Light3D::get_projector_offset);
+
 	ClassDB::bind_method(D_METHOD("set_temperature", "temperature"), &Light3D::set_temperature);
 	ClassDB::bind_method(D_METHOD("get_temperature"), &Light3D::get_temperature);
 	ClassDB::bind_method(D_METHOD("get_correlated_color"), &Light3D::get_correlated_color);
@@ -398,8 +422,13 @@ void Light3D::_bind_methods() {
 	ADD_PROPERTYI(PropertyInfo(Variant::FLOAT, "light_energy", PROPERTY_HINT_RANGE, "0,16,0.001,or_greater"), "set_param", "get_param", PARAM_ENERGY);
 	ADD_PROPERTYI(PropertyInfo(Variant::FLOAT, "light_indirect_energy", PROPERTY_HINT_RANGE, "0,16,0.001,or_greater"), "set_param", "get_param", PARAM_INDIRECT_ENERGY);
 	ADD_PROPERTYI(PropertyInfo(Variant::FLOAT, "light_volumetric_fog_energy", PROPERTY_HINT_RANGE, "0,16,0.001,or_greater"), "set_param", "get_param", PARAM_VOLUMETRIC_FOG_ENERGY);
+
 	// Only allow texture types that display correctly.
+	ADD_SUBGROUP("Projector", "light_projector_");
 	ADD_PROPERTY(PropertyInfo(Variant::OBJECT, "light_projector", PROPERTY_HINT_RESOURCE_TYPE, "Texture2D,-AnimatedTexture,-AtlasTexture,-CameraTexture,-CanvasTexture,-MeshTexture,-Texture2DRD,-ViewportTexture"), "set_projector", "get_projector");
+	ADD_PROPERTY(PropertyInfo(Variant::VECTOR2, "light_projector_scale", PROPERTY_HINT_NONE, "suffix:px"), "set_projector_scale", "get_projector_scale");
+	ADD_PROPERTY(PropertyInfo(Variant::VECTOR2, "light_projector_offset"), "set_projector_offset", "get_projector_offset");
+
 	ADD_PROPERTYI(PropertyInfo(Variant::FLOAT, "light_size", PROPERTY_HINT_RANGE, "0,1,0.001,or_greater,suffix:m"), "set_param", "get_param", PARAM_SIZE);
 	ADD_PROPERTYI(PropertyInfo(Variant::FLOAT, "light_angular_distance", PROPERTY_HINT_RANGE, "0,90,0.01,degrees"), "set_param", "get_param", PARAM_SIZE);
 	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "light_negative"), "set_negative", "is_negative");
@@ -560,7 +589,7 @@ void DirectionalLight3D::_validate_property(PropertyInfo &p_property) const {
 		p_property.usage = PROPERTY_USAGE_NO_EDITOR;
 	}
 
-	if (p_property.name == "light_size" || p_property.name == "light_projector") {
+	if (p_property.name == "light_size") {
 		// Not implemented in DirectionalLight3D (`light_size` is replaced by `light_angular_distance`).
 		p_property.usage = PROPERTY_USAGE_NONE;
 	}
@@ -614,6 +643,7 @@ DirectionalLight3D::DirectionalLight3D() :
 	set_shadow_mode(SHADOW_PARALLEL_4_SPLITS);
 	blend_splits = false;
 	set_sky_mode(SKY_MODE_LIGHT_AND_SKY);
+	set_projector_scale(Vector2(1, 1));
 }
 
 void OmniLight3D::set_shadow_mode(ShadowMode p_mode) {

scene/3d/light_3d.h

@@ -84,6 +84,8 @@ class Light3D : public VisualInstance3D {
 	void _update_visibility();
 	BakeMode bake_mode = BAKE_DYNAMIC;
 	Ref<Texture2D> projector;
+	Vector2 projector_scale;
+	Vector2 projector_offset;
 	Color correlated_color = Color(1.0, 1.0, 1.0);
 	float temperature = 6500.0;
 
@@ -145,6 +147,12 @@ class Light3D : public VisualInstance3D {
 	void set_projector(const Ref<Texture2D> &p_texture);
 	Ref<Texture2D> get_projector() const;
 
+	void set_projector_scale(const Vector2 &p_scale);
+	Vector2 get_projector_scale() const;
+
+	void set_projector_offset(const Vector2 &p_offset);
+	Vector2 get_projector_offset() const;
+
 	void set_temperature(const float p_temperature);
 	float get_temperature() const;
 	Color get_correlated_color() const;

servers/rendering/dummy/storage/light_storage.h

@@ -73,6 +73,8 @@ class LightStorage : public RendererLightStorage {
 	virtual void light_set_param(RID p_light, RS::LightParam p_param, float p_value) override {}
 	virtual void light_set_shadow(RID p_light, bool p_enabled) override {}
 	virtual void light_set_projector(RID p_light, RID p_texture) override {}
+	virtual void light_set_projector_scale(RID p_light, const Vector2 &p_scale) override {}
+	virtual void light_set_projector_offset(RID p_light, const Vector2 &p_offset) override {}
 	virtual void light_set_negative(RID p_light, bool p_enable) override {}
 	virtual void light_set_cull_mask(RID p_light, uint32_t p_mask) override {}
 	virtual void light_set_distance_fade(RID p_light, bool p_enabled, float p_begin, float p_shadow, float p_length) override {}