New Sky generator node.

PixelComposer.resource_order

@@ -188,6 +188,7 @@
     {"name":"blinker","order":19,"path":"folders/shader/generator/blinker.yy",},
     {"name":"cell","order":20,"path":"folders/shader/generator/cell.yy",},
     {"name":"grid","order":18,"path":"folders/shader/generator/grid.yy",},
+    {"name":"sky model","order":31,"path":"folders/shader/generator/sky model.yy",},
     {"name":"interpret","order":17,"path":"folders/shader/generator/interpret.yy",},
     {"name":"random_shape","order":21,"path":"folders/shader/generator/random_shape.yy",},
     {"name":"reaction_diffusion","order":22,"path":"folders/shader/generator/reaction_diffusion.yy",},
@@ -1112,6 +1113,7 @@
     {"name":"node_shard_noise","order":12,"path":"scripts/node_shard_noise/node_shard_noise.yy",},
     {"name":"node_shell","order":13,"path":"scripts/node_shell/node_shell.yy",},
     {"name":"node_skew","order":11,"path":"scripts/node_skew/node_skew.yy",},
+    {"name":"node_sky","order":24,"path":"scripts/node_sky/node_sky.yy",},
     {"name":"node_slideshow","order":28,"path":"scripts/node_slideshow/node_slideshow.yy",},
     {"name":"node_smear","order":12,"path":"scripts/node_smear/node_smear.yy",},
     {"name":"node_smoke_add_collider","order":6,"path":"scripts/node_smoke_add_collider/node_smoke_add_collider.yy",},

PixelComposer.yyp

@@ -299,6 +299,7 @@
     {"$GMFolder":"","%Name":"blinker","folderPath":"folders/shader/generator/blinker.yy","name":"blinker","resourceType":"GMFolder","resourceVersion":"2.0",},
     {"$GMFolder":"","%Name":"cell","folderPath":"folders/shader/generator/cell.yy","name":"cell","resourceType":"GMFolder","resourceVersion":"2.0",},
     {"$GMFolder":"","%Name":"grid","folderPath":"folders/shader/generator/grid.yy","name":"grid","resourceType":"GMFolder","resourceVersion":"2.0",},
+    {"$GMFolder":"","%Name":"sky model","folderPath":"folders/shader/generator/sky model.yy","name":"sky model","resourceType":"GMFolder","resourceVersion":"2.0",},
     {"$GMFolder":"","%Name":"interpret","folderPath":"folders/shader/generator/interpret.yy","name":"interpret","resourceType":"GMFolder","resourceVersion":"2.0",},
     {"$GMFolder":"","%Name":"random_shape","folderPath":"folders/shader/generator/random_shape.yy","name":"random_shape","resourceType":"GMFolder","resourceVersion":"2.0",},
     {"$GMFolder":"","%Name":"reaction_diffusion","folderPath":"folders/shader/generator/reaction_diffusion.yy","name":"reaction_diffusion","resourceType":"GMFolder","resourceVersion":"2.0",},
@@ -1704,6 +1705,7 @@
     {"id":{"name":"node_shard_noise","path":"scripts/node_shard_noise/node_shard_noise.yy",},},
     {"id":{"name":"node_shell","path":"scripts/node_shell/node_shell.yy",},},
     {"id":{"name":"node_skew","path":"scripts/node_skew/node_skew.yy",},},
+    {"id":{"name":"node_sky","path":"scripts/node_sky/node_sky.yy",},},
     {"id":{"name":"node_slideshow","path":"scripts/node_slideshow/node_slideshow.yy",},},
     {"id":{"name":"node_smear","path":"scripts/node_smear/node_smear.yy",},},
     {"id":{"name":"node_smoke_add_collider","path":"scripts/node_smoke_add_collider/node_smoke_add_collider.yy",},},
@@ -2438,6 +2440,7 @@
     {"id":{"name":"sh_shape","path":"shaders/sh_shape/sh_shape.yy",},},
     {"id":{"name":"sh_simplex","path":"shaders/sh_simplex/sh_simplex.yy",},},
     {"id":{"name":"sh_skew","path":"shaders/sh_skew/sh_skew.yy",},},
+    {"id":{"name":"sh_sky_preetham","path":"shaders/sh_sky_preetham/sh_sky_preetham.yy",},},
     {"id":{"name":"sh_slice_spritesheet_empty_scan","path":"shaders/sh_slice_spritesheet_empty_scan/sh_slice_spritesheet_empty_scan.yy",},},
     {"id":{"name":"sh_smear","path":"shaders/sh_smear/sh_smear.yy",},},
     {"id":{"name":"sh_solid","path":"shaders/sh_solid/sh_solid.yy",},},

scripts/node_registry/node_registry.gml

@@ -752,6 +752,7 @@ function __initNodes() {
 		addNodeObject(generator, "Solid",					s_node_solid,				"Node_Solid",				[1, Node_Solid],,			"Create image of a single color.");
 		addNodeObject(generator, "Draw Gradient",			s_node_gradient,			"Node_Gradient",			[1, Node_Gradient],,		"Create image from gradient.");
 		addNodeObject(generator, "Draw 4 Points Gradient",	s_node_gradient_4points,	"Node_Gradient_Points",		[1, Node_Gradient_Points],, "Create image from 4 color points.");
+		/**/ addNodeObject(generator, "Sky",						s_node_gradient_4points,	"Node_Sky",					[1, Node_Sky],, "Generate sky texture using different model.");
 		
 		ds_list_add(generator, "Drawer");
 		addNodeObject(generator, "Draw Line",			s_node_line,				"Node_Line",				[1, Node_Line],,										"Draw line on an image. Connect path data to it to draw line from path.");

scripts/node_sky/node_sky.gml

@@ -0,0 +1,63 @@
+function Node_Sky(_x, _y, _group = noone) : Node_Processor(_x, _y, _group) constructor {
+	name = "Sky";
+	
+	newInput(0, nodeValue_Dimension(self));
+	
+	newInput(1, nodeValue_Enum_Scroll("Model", self, 0, [ "Preetham" ]));
+	
+	newInput(2, nodeValue_Float("Turbidity", self, 2));
+	
+	newInput(3, nodeValue_Float("Azimuth", self, 0))
+	    .setDisplay(VALUE_DISPLAY.slider, { range: [ -180, 180, 1 ] });
+	
+	newInput(4, nodeValue_Float("Inclination", self, 0))
+	    .setDisplay(VALUE_DISPLAY.slider, { range: [ -180, 180, 1 ] });
+	
+	newInput(5, nodeValue_Vec2("Scale", self, [ 1, 1 ]));
+	
+	newInput(6, nodeValue_Vec2("Offset", self, [ 0, 0 ]));
+	
+	newOutput(0, nodeValue_Output("Surface out", self, VALUE_TYPE.surface, noone));
+	
+	input_display_list = [ 0, 
+	    ["Transform", false], 6, 5, 
+		["Sky",	      false], 1, 2, 3, 4, 
+	];
+	
+	attribute_surface_depth();
+	
+	static drawOverlay = function(hover, active, _x, _y, _s, _mx, _my, _snx, _sny) {
+		var _hov = false;
+		
+		var hv = inputs[6].drawOverlay(hover, active, _x, _y, _s, _mx, _my, _snx, _sny); _hov |= hv;
+		
+		return _hov;
+	}
+	
+	static processData = function(_outSurf, _data, _output_index, _array_index) {
+		var _dim = _data[0];
+		var _mod = _data[1];
+		var _tur = _data[2];
+		var _azi = _data[3];
+		var _inc = _data[4];
+		var _sca = _data[5];
+		var _pos = _data[6];
+		
+		if(_mod == 0) {
+    		surface_set_shader(_outSurf, sh_sky_preetham);
+    			DRAW_CLEAR
+    			
+    			shader_set_2("dimension",   _dim);
+    			shader_set_2("position",    _pos);
+    			shader_set_2("scale",       _sca);
+    			shader_set_f("turbidity",   _tur);
+    			shader_set_f("azimuth",     degtorad(_azi));
+    			shader_set_f("inclination", degtorad(_inc));
+    			
+    			draw_empty();
+    		surface_reset_shader();
+		}
+		
+		return _outSurf;
+	}
+}

scripts/node_sky/node_sky.yy

@@ -0,0 +1,13 @@
+{
+  "$GMScript":"v1",
+  "%Name":"node_sky",
+  "isCompatibility":false,
+  "isDnD":false,
+  "name":"node_sky",
+  "parent":{
+    "name":"generator",
+    "path":"folders/nodes/data/generator.yy",
+  },
+  "resourceType":"GMScript",
+  "resourceVersion":"2.0",
+}

shaders/sh_sky_preetham/sh_sky_preetham.fsh

@@ -0,0 +1,117 @@
+#define PI     3.14159265359
+
+varying vec2 v_vTexcoord;
+varying vec4 v_vColour;
+
+uniform vec2  dimension;
+uniform vec2  position;
+uniform vec2  scale;
+
+uniform float turbidity;
+uniform float azimuth;
+uniform float inclination;
+
+float saturatedDot( in vec3 a, in vec3 b ) {
+	return max( dot( a, b ), 0.0 );   
+}
+
+vec3 computeSphericalCoordinates( in vec2 uv ) {
+	float theta = uv.x * 2.0 * PI;
+	float phi   = uv.y * PI;
+	return vec3(cos(theta) * sin(phi), sin(theta) * sin(phi), cos(phi));
+}
+
+vec3 YxyToXYZ( in vec3 Yxy ) {
+	float Y = Yxy.r;
+	float x = Yxy.g;
+	float y = Yxy.b;
+
+	float X = x * ( Y / y );
+	float Z = ( 1.0 - x - y ) * ( Y / y );
+
+	return vec3(X,Y,Z);
+}
+
+vec3 XYZToRGB( in vec3 XYZ ) {
+	// CIE/E
+	mat3 M = mat3
+	(
+		 2.3706743, -0.9000405, -0.4706338,
+		-0.5138850,  1.4253036,  0.0885814,
+ 		 0.0052982, -0.0146949,  1.0093968
+	);
+
+	return XYZ * M;
+}
+
+
+vec3 YxyToRGB( in vec3 Yxy ) {
+	vec3 XYZ = YxyToXYZ( Yxy );
+	vec3 RGB = XYZToRGB( XYZ );
+	return RGB;
+}
+
+void calculatePerezDistribution( in float t, out vec3 A, out vec3 B, out vec3 C, out vec3 D, out vec3 E ) {
+	A = vec3(  0.1787 * t - 1.4630, -0.0193 * t - 0.2592, -0.0167 * t - 0.2608 );
+	B = vec3( -0.3554 * t + 0.4275, -0.0665 * t + 0.0008, -0.0950 * t + 0.0092 );
+	C = vec3( -0.0227 * t + 5.3251, -0.0004 * t + 0.2125, -0.0079 * t + 0.2102 );
+	D = vec3(  0.1206 * t - 2.5771, -0.0641 * t - 0.8989, -0.0441 * t - 1.6537 );
+	E = vec3( -0.0670 * t + 0.3703, -0.0033 * t + 0.0452, -0.0109 * t + 0.0529 );
+}
+
+vec3 calculateZenithLuminanceYxy( in float t, in float thetaS ) {
+	float chi  	 	= ( 4.0 / 9.0 - t / 120.0 ) * ( PI - 2.0 * thetaS );
+	float Yz   	 	= ( 4.0453 * t - 4.9710 ) * tan( chi ) - 0.2155 * t + 2.4192;
+
+	float theta2 	= thetaS * thetaS;
+    float theta3 	= theta2 * thetaS;
+    float T 	 	= t;
+    float T2 	 	= t * t;
+
+	float xz =
+      ( 0.00165 * theta3 - 0.00375 * theta2 + 0.00209 * thetaS + 0.0)     * T2 +
+      (-0.02903 * theta3 + 0.06377 * theta2 - 0.03202 * thetaS + 0.00394) * T +
+      ( 0.11693 * theta3 - 0.21196 * theta2 + 0.06052 * thetaS + 0.25886);
+
+    float yz =
+      ( 0.00275 * theta3 - 0.00610 * theta2 + 0.00317 * thetaS + 0.0)     * T2 +
+      (-0.04214 * theta3 + 0.08970 * theta2 - 0.04153 * thetaS + 0.00516) * T +
+      ( 0.15346 * theta3 - 0.26756 * theta2 + 0.06670 * thetaS + 0.26688);
+
+	return vec3( Yz, xz, yz );
+}
+
+vec3 calculatePerezLuminanceYxy( in float theta, in float gamma, in vec3 A, in vec3 B, in vec3 C, in vec3 D, in vec3 E ) {
+	return ( 1.0 + A * exp( B / cos( theta ) ) ) * ( 1.0 + C * exp( D * gamma ) + E * cos( gamma ) * cos( gamma ) );
+}
+
+vec3 calculateSkyLuminanceRGB( in vec3 s, in vec3 e, in float t ) {
+	vec3 A, B, C, D, E;
+	calculatePerezDistribution( t, A, B, C, D, E );
+    
+	float thetaS = acos( saturatedDot( s, vec3(0,1,0) ) );
+	float thetaE = acos( saturatedDot( e, vec3(0,1,0) ) );
+	float gammaE = acos( saturatedDot( s, e )		   );
+
+	vec3 Yz = calculateZenithLuminanceYxy( t, thetaS );
+
+	vec3 fThetaGamma = calculatePerezLuminanceYxy( thetaE, gammaE, A, B, C, D, E );
+	vec3 fZeroThetaS = calculatePerezLuminanceYxy( 0.0,    thetaS, A, B, C, D, E );
+
+	vec3 Yp = Yz * ( fThetaGamma / fZeroThetaS );
+
+	return YxyToRGB( Yp );
+}
+
+void main() {
+    vec2 uv = v_vTexcoord;
+    uv   = (uv - position / dimension);
+    uv.y = 1. - uv.y;
+    uv  /= scale;
+    
+    vec3 sunDir     	= normalize( vec3( sin( inclination ) * cos( azimuth ), cos( inclination ), sin( inclination ) * sin(azimuth) ) );
+    vec3 viewDir  		= -computeSphericalCoordinates( uv ).xzy;
+    vec3 skyLuminance 	= calculateSkyLuminanceRGB( sunDir, viewDir, turbidity );
+    
+    gl_FragColor = vec4( skyLuminance * 0.05, 1.0 );
+}

shaders/sh_sky_preetham/sh_sky_preetham.vsh

@@ -0,0 +1,19 @@
+//
+// Simple passthrough vertex shader
+//
+attribute vec3 in_Position;                  // (x,y,z)
+//attribute vec3 in_Normal;                  // (x,y,z)     unused in this shader.
+attribute vec4 in_Colour;                    // (r,g,b,a)
+attribute vec2 in_TextureCoord;              // (u,v)
+
+varying vec2 v_vTexcoord;
+varying vec4 v_vColour;
+
+void main()
+{
+    vec4 object_space_pos = vec4( in_Position.x, in_Position.y, in_Position.z, 1.0);
+    gl_Position = gm_Matrices[MATRIX_WORLD_VIEW_PROJECTION] * object_space_pos;
+    
+    v_vColour = in_Colour;
+    v_vTexcoord = in_TextureCoord;
+}

shaders/sh_sky_preetham/sh_sky_preetham.yy

@@ -0,0 +1,12 @@
+{
+  "$GMShader":"",
+  "%Name":"sh_sky_preetham",
+  "name":"sh_sky_preetham",
+  "parent":{
+    "name":"sky model",
+    "path":"folders/shader/generator/sky model.yy",
+  },
+  "resourceType":"GMShader",
+  "resourceVersion":"2.0",
+  "type":1,
+}