Improved default directional shadow params, added bias split scale, closes #9828

drivers/gles3/rasterizer_scene_gles3.cpp

@@ -4445,9 +4445,10 @@ void RasterizerSceneGLES3::render_shadow(RID p_light, RID p_shadow_atlas, int p_
 			}
 		}
 
+		float bias_mult = Math::lerp(1.0f, light_instance->shadow_transform[p_pass].bias_scale, light->param[VS::LIGHT_PARAM_SHADOW_BIAS_SPLIT_SCALE]);
 		zfar = light->param[VS::LIGHT_PARAM_RANGE];
-		bias = light->param[VS::LIGHT_PARAM_SHADOW_BIAS] * light_instance->shadow_transform[p_pass].bias_scale;
-		normal_bias = light->param[VS::LIGHT_PARAM_SHADOW_NORMAL_BIAS] * light_instance->shadow_transform[p_pass].bias_scale;
+		bias = light->param[VS::LIGHT_PARAM_SHADOW_BIAS] * bias_mult;
+		normal_bias = light->param[VS::LIGHT_PARAM_SHADOW_NORMAL_BIAS] * bias_mult;
 		fbo = directional_shadow.fbo;
 		vp_height = directional_shadow.size;
 

drivers/gles3/rasterizer_storage_gles3.cpp

@@ -4448,6 +4448,7 @@ RID RasterizerStorageGLES3::light_create(VS::LightType p_type) {
 	light->param[VS::LIGHT_PARAM_SHADOW_SPLIT_2_OFFSET] = 0.3;
 	light->param[VS::LIGHT_PARAM_SHADOW_SPLIT_3_OFFSET] = 0.6;
 	light->param[VS::LIGHT_PARAM_SHADOW_NORMAL_BIAS] = 0.1;
+	light->param[VS::LIGHT_PARAM_SHADOW_BIAS_SPLIT_SCALE] = 0.1;
 
 	light->color = Color(1, 1, 1, 1);
 	light->shadow = false;

scene/3d/light.cpp

@@ -334,6 +334,7 @@ void DirectionalLight::_bind_methods() {
 	ADD_PROPERTYI(PropertyInfo(Variant::REAL, "directional_shadow_split_3", PROPERTY_HINT_RANGE, "0,1,0.001"), "set_param", "get_param", PARAM_SHADOW_SPLIT_3_OFFSET);
 	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "directional_shadow_blend_splits"), "set_blend_splits", "is_blend_splits_enabled");
 	ADD_PROPERTYI(PropertyInfo(Variant::REAL, "directional_shadow_normal_bias", PROPERTY_HINT_RANGE, "0,16,0.01"), "set_param", "get_param", PARAM_SHADOW_NORMAL_BIAS);
+	ADD_PROPERTYI(PropertyInfo(Variant::REAL, "directional_shadow_bias_split_scale", PROPERTY_HINT_RANGE, "0,1,0.01"), "set_param", "get_param", PARAM_SHADOW_BIAS_SPLIT_SCALE);
 
 	BIND_ENUM_CONSTANT(SHADOW_ORTHOGONAL);
 	BIND_ENUM_CONSTANT(SHADOW_PARALLEL_2_SPLITS);
@@ -343,9 +344,10 @@ void DirectionalLight::_bind_methods() {
 DirectionalLight::DirectionalLight()
 	: Light(VisualServer::LIGHT_DIRECTIONAL) {
 
-	set_param(PARAM_SHADOW_NORMAL_BIAS, 0.2);
-	set_param(PARAM_SHADOW_BIAS, 1.0);
+	set_param(PARAM_SHADOW_NORMAL_BIAS, 0.8);
+	set_param(PARAM_SHADOW_BIAS, 0.1);
 	set_param(PARAM_SHADOW_MAX_DISTANCE, 200);
+	set_param(PARAM_SHADOW_BIAS_SPLIT_SCALE, 0.25);
 	set_shadow_mode(SHADOW_PARALLEL_4_SPLITS);
 
 	blend_splits = false;

scene/3d/light.h

@@ -58,6 +58,7 @@ public:
 		PARAM_SHADOW_SPLIT_3_OFFSET = VS::LIGHT_PARAM_SHADOW_SPLIT_3_OFFSET,
 		PARAM_SHADOW_NORMAL_BIAS = VS::LIGHT_PARAM_SHADOW_NORMAL_BIAS,
 		PARAM_SHADOW_BIAS = VS::LIGHT_PARAM_SHADOW_BIAS,
+		PARAM_SHADOW_BIAS_SPLIT_SCALE = VS::LIGHT_PARAM_SHADOW_BIAS_SPLIT_SCALE,
 		PARAM_MAX = VS::LIGHT_PARAM_MAX
 	};
 

servers/visual_server.h

@@ -358,6 +358,7 @@ public:
 		LIGHT_PARAM_SHADOW_SPLIT_3_OFFSET,
 		LIGHT_PARAM_SHADOW_NORMAL_BIAS,
 		LIGHT_PARAM_SHADOW_BIAS,
+		LIGHT_PARAM_SHADOW_BIAS_SPLIT_SCALE,
 		LIGHT_PARAM_MAX
 	};