Add ability to clamp values in GUIs

clamp = FLOOR # Any value smaller than 0.95 is treated as 0
clamp = CEIL  # Any value greater than 0.05 is treated as 1

src/main/java/cam72cam/immersiverailroading/gui/overlay/GuiBuilder.java

@@ -51,6 +51,7 @@ public class GuiBuilder {
     private final boolean invert;
     private final boolean translucent;
     private final boolean toggle;
+    private final ClampMode clamp;
     private final float tlx;
     private final float tly;
     private final float rotx;
@@ -102,6 +103,16 @@ public static Vertical from(String pos_y) {
         }
     }
 
+    private enum ClampMode {
+        NONE, FLOOR, CEIL;
+        public static ClampMode from(String value) {
+            if (value != null) {
+                return valueOf(value.toUpperCase(Locale.ROOT));
+            }
+            return NONE;
+        }
+    }
+
     private static DataBlock processImports(DataBlock data) throws IOException {
         // This is kinda weird as it appends the import to the current block instead of inserting it in the current
         // element list.  It's definitely a bit of a footgun.  The "correct" way to do this would be to make import part
@@ -167,6 +178,7 @@ protected GuiBuilder(DataBlock data) throws IOException {
         this.invert = data.getValue("invert").asBoolean(false);
         this.translucent = data.getValue("translucent").asBoolean(data.getValue("hide").asBoolean(false));
         this.toggle = data.getValue("toggle").asBoolean(false);
+        this.clamp = ClampMode.from(data.getValue("clamp").asString());
 
         DataBlock tl = data.getBlock("translate");
         if (tl != null) {
@@ -271,6 +283,13 @@ private float getValue(EntityRollingStock stock) {
             value = texture_variant.equals(stock.getTexture()) ? 1 : 0;
         }
 
+        switch (clamp) {
+            case FLOOR:
+                value = value < 0.95 ? 0 : 1;
+            case CEIL:
+                value = value < 0.05 ? 0 : 1;
+        }
+
         if (invert) {
             value = 1 - value;
         }