Adding stigi - no superposition in shader

maps/basic_setup.tscn

@@ -1,4 +1,4 @@
-[gd_scene load_steps=23 format=3 uid="uid://b8p2h0rmwy7qn"]
+[gd_scene load_steps=24 format=3 uid="uid://b8p2h0rmwy7qn"]
 
 [ext_resource type="Material" uid="uid://dpegsmygxcfmv" path="res://maps/materials/basic_ground.material" id="1_lodye"]
 [ext_resource type="Shader" path="res://maps/shaders/khanat_sky.gdshader" id="1_mheqi"]
@@ -6,6 +6,7 @@
 [ext_resource type="PackedScene" uid="uid://cveshwnu272vf" path="res://maps/objects/ramp-complex.tscn" id="2_4eueh"]
 [ext_resource type="Texture2D" uid="uid://y0ka7tysfp6b" path="res://maps/textures/zabr_tex_001.png" id="3_bgghj"]
 [ext_resource type="PackedScene" uid="uid://omess6wwwwcq" path="res://maps/objects/ramp-moving.tscn" id="3_bvbgo"]
+[ext_resource type="Texture2D" uid="uid://dlxp52r0wnwlq" path="res://maps/textures/stigi_tex_001.png" id="3_jqgsm"]
 [ext_resource type="PackedScene" uid="uid://dvsl8x3lb1h4e" path="res://maps/objects/moutain.tscn" id="3_rbp35"]
 [ext_resource type="PackedScene" path="res://maps/objects/cave.tscn" id="4_pc85h"]
 [ext_resource type="PackedScene" uid="uid://b61edh0bre65c" path="res://maps/objects/ramp.tscn" id="5_dfm8h"]
@@ -34,8 +35,11 @@ shader_param/samayun_arc = 50.0
 shader_param/samayun_position = Vector3(2.038, 0.584, -0.995)
 shader_param/zabr_arc = 15.0
 shader_param/zabr_position = Vector3(0.6, 0.03, -0.342)
+shader_param/stigi_arc = null
+shader_param/stigi_position = Vector3(0.688, 0.03, -0.342)
 shader_param/samayun = ExtResource( "1_thm7k" )
 shader_param/zabr = ExtResource( "3_bgghj" )
+shader_param/stigi = ExtResource( "3_jqgsm" )
 
 [sub_resource type="Sky" id="Sky_fa16p"]
 sky_material = SubResource( "ShaderMaterial_s2q0l" )

maps/shaders/khanat_sky.gdshader

@@ -19,13 +19,17 @@ uniform float dither_strength : hint_range(0, 10) = 1.0;
 uniform sampler2D night_sky : hint_black_albedo;
 
 uniform sampler2D samayun : hint_albedo;
-uniform float samayun_arc = 25 ;
+uniform float samayun_arc = 45 ;
 uniform vec3 samayun_position = vec3( 0.0, 0.5, 0.0 );
 
 uniform sampler2D zabr : hint_albedo;
-uniform float zabr_arc = 12 ;
+uniform float zabr_arc = 15 ;
 uniform vec3 zabr_position = vec3( 0.0, 0.7, 0.0 );
 
+uniform sampler2D stigi : hint_albedo;
+uniform float stigi_arc = 8 ;
+uniform vec3 stigi_position = vec3( 0.0, 0.8, 0.0 );
+
 const vec3 UP = vec3( 0.0, 1.0, 0.0 );
 
 // Sun constants
@@ -104,6 +108,7 @@ void sky() {
 	// Calculate respective scales of celestial objects
 	float samayun_scale = radians(samayun_arc) ;
 	float zabr_scale = radians(zabr_arc) ;
+	float stigi_scale = radians(stigi_arc) ;
 	
 	// Adding Samayun
 	if (length(EYEDIR - normalize(samayun_position)) < samayun_scale / 2.0) { // we are in the area of the sky where samayun is placed
@@ -135,4 +140,19 @@ void sky() {
 				COLOR += texture(zabr,  vec2(z_x,z_y) / zabr_scale + vec2(0.5)).rgb * texture(zabr, vec2(z_x,z_y) / zabr_scale + vec2(0.5)).a;
 			}
 		}
+	// Adding stigi
+	if (length(EYEDIR - normalize(stigi_position)) < stigi_scale / 2.0) { // we are in the area of the sky where stigi is placed
+		//We define a local plane tangent to the skydome at stigi_position
+        //We work with everything normalized
+        vec3 s_n1 = normalize(cross(stigi_position,vec3(0.0,1.0,0.0))) ;
+        vec3 s_n2 = normalize(cross(stigi_position,s_n1)) ;
+		//We project EYEDIR on this plane with an approximate correction for projection
+        float s_x = dot(EYEDIR,s_n1) * 0.89 ;
+        float s_y = dot(EYEDIR,s_n2) * 0.89 ;
+			// If samayun is nearer at this place, do nothing
+		if (length(EYEDIR - normalize(samayun_position)) < samayun_scale / 2.0 && length(samayun_position) < length(stigi_position)){
+			} else { // Add stigi to the sky
+				COLOR += texture(stigi,  vec2(s_x,s_y) / stigi_scale + vec2(0.5)).rgb * texture(stigi, vec2(s_x,s_y) / stigi_scale + vec2(0.5)).a;
+			}
+		}
 }

maps/textures/stigi_tex_001.png.import

@@ -0,0 +1,35 @@
+[remap]
+
+importer="texture"
+type="CompressedTexture2D"
+uid="uid://dlxp52r0wnwlq"
+path.s3tc="res://.godot/imported/stigi_tex_001.png-422a9b36925acddfd148694fe140318a.s3tc.ctex"
+path.etc2="res://.godot/imported/stigi_tex_001.png-422a9b36925acddfd148694fe140318a.etc2.ctex"
+metadata={
+"imported_formats": ["s3tc", "etc2"],
+"vram_texture": true
+}
+
+[deps]
+
+source_file="res://maps/textures/stigi_tex_001.png"
+dest_files=["res://.godot/imported/stigi_tex_001.png-422a9b36925acddfd148694fe140318a.s3tc.ctex", "res://.godot/imported/stigi_tex_001.png-422a9b36925acddfd148694fe140318a.etc2.ctex"]
+
+[params]
+
+compress/mode=2
+compress/lossy_quality=0.7
+compress/hdr_compression=1
+compress/bptc_ldr=0
+compress/normal_map=0
+compress/channel_pack=0
+mipmaps/generate=true
+mipmaps/limit=-1
+roughness/mode=0
+roughness/src_normal=""
+process/fix_alpha_border=true
+process/premult_alpha=false
+process/normal_map_invert_y=false
+process/hdr_as_srgb=false
+process/size_limit=0
+detect_3d/compress_to=0