Gateway destinations (#21040)

* Gateway generation

* Gateway stuff

* gatewehs

* mercenaries

* play area

* Range fixes and tweaks

* weh

* Gateway UI polish

* Lots of fixes

* Knock some items off

* Fix dungeon spawning

Realistically we should probably be using a salvage job.

* wahwah

* wehvs

* expression

* weh

* eee

* a

* a

* WEH

* frfr

* Gatwey

* Fix gateway windows

* Fix gateway windows

* a

* a

* Better layer masking

* a

* a

* Noise fixes

* a

* Fix fractal calculations

* a

* More fixes

* Fixes

* Add layers back in

* Fixes

* namespaces and ftl

* Other TODO

* Fix distance

* Cleanup

* Fix test

Resources/Textures/Shaders/world_gradient_circle.swsl

@@ -0,0 +1,27 @@
+// Has 2 circles, an inner one that is unaffected and an outer one.
+light_mode unshaded;
+
+const highp vec4 color = vec4(1.0, 1.0, 1.0, 1.0);
+
+// Position of the center in pixel terms.
+uniform highp vec2 position;
+uniform highp float maxRange;
+uniform highp float minRange;
+uniform highp float bufferRange;
+uniform highp float gradient;
+
+void fragment() {
+	highp float distance = length(FRAGCOORD.xy - position);
+
+	if (distance > maxRange) {
+		discard;
+	}
+	else if (distance < minRange) {
+		COLOR = color;
+	}
+	else {
+		
+        	highp float ratio = 1.0 - pow((distance - minRange) / bufferRange, gradient);
+		COLOR = vec4(color.x, color.y, color.z, ratio);
+	}
+}