Added a special resource to contain unique instances of BugMarker materials.

Materials/BugMarker/bug_marker.gdshader

@@ -0,0 +1,25 @@
+// NOTE: Shader automatically converted from Godot Engine 4.2.2.stable's StandardMaterial3D.
+
+shader_type spatial;
+render_mode blend_mix,depth_test_disabled,cull_disabled,unshaded;
+
+uniform vec3 colour : source_color = vec3(1.0f);
+uniform sampler2D msdf_icon : filter_linear_mipmap,hint_default_black;
+uniform float shape_thickness : hint_range(0.0f,1.0f,0.01) = 0.95f;
+uniform vec3 line_colour : source_color = vec3(0.0f);
+uniform float line_thickness : hint_range(0.0f,1.0f,0.01) = 0.0f;
+uniform bool billboard = false;
+
+void vertex() {
+	if (billboard) {
+		MODELVIEW_MATRIX = VIEW_MATRIX * mat4(INV_VIEW_MATRIX[0], INV_VIEW_MATRIX[1], INV_VIEW_MATRIX[2], MODEL_MATRIX[3]);
+		MODELVIEW_MATRIX = MODELVIEW_MATRIX * mat4(vec4(length(MODEL_MATRIX[0].xyz), 0.0, 0.0, 0.0), vec4(0.0, length(MODEL_MATRIX[1].xyz), 0.0, 0.0), vec4(0.0, 0.0, length(MODEL_MATRIX[2].xyz), 0.0), vec4(0.0, 0.0, 0.0, 1.0));
+		MODELVIEW_NORMAL_MATRIX = mat3(MODELVIEW_MATRIX);
+	}
+}
+
+void fragment() {
+	vec4 albedo_tex = texture(msdf_icon, UV);
+	if (step(shape_thickness, albedo_tex.r) > 0.5f) { discard; }
+	ALBEDO = (step(shape_thickness-line_thickness, albedo_tex.r) > 0.5f) ? pow(line_colour, vec3(0.4545454545)) : pow(colour.rgb, vec3(0.4545454545));
+}