Add customizable overlay colors, works for base overlay, spawn, and slime.

I left minerals as it is so you have to still define the minerals option to get that to work.

overviewer_core/src/primitives/overlay.c

@@ -17,28 +17,59 @@
 
 #include "overlay.h"
 
+static OverlayColor default_color[] = { 200, 200, 255, 155 };
+
 static void get_color(void *data, RenderState *state,
                       unsigned char *r, unsigned char *g, unsigned char *b, unsigned char *a) {
-    *r = 200;
-    *g = 200;
-    *b = 255;
-    *a = 155;
+    RenderPrimitiveOverlay* self = (RenderPrimitiveOverlay *)data;
+
+    *r = self->color->r;
+    *g = self->color->g;
+    *b = self->color->b;
+    *a = self->color->a;
 }
 
 static int
 overlay_start(void *data, RenderState *state, PyObject *support) {
+    PyObject *opt = NULL;
+    OverlayColor *color = NULL;
     RenderPrimitiveOverlay *self = (RenderPrimitiveOverlay *)data;
     
     self->facemask_top = PyObject_GetAttrString(support, "facemask_top");
     self->white_color = PyObject_GetAttrString(support, "whitecolor");
     self->get_color = get_color;
     
+    color = self->color = calloc(1, sizeof(OverlayColor));
+
+    if (color == NULL) {
+        return 1;
+    }
+
+    if(!render_mode_parse_option(support, "overlay_color", "bbbb", &(color->r), &(color->g), &(color->b), &(color->a))) {
+	if(PyErr_Occurred())
+            PyErr_Clear();
+        free(color);
+        self->color = default_color;
+        // Check if it is None, if it is, continue and use the default, if it isn't, return an error
+        if(render_mode_parse_option(support, "overlay_color", "O", &(opt))) {
+            // If it is an object, check to see if it is None, if it is, use the default.
+            if(opt && opt != Py_None) {
+                return 1;
+            }
+        } else {
+            return 1;
+        }
+    }
     return 0;
 }
 
 static void
 overlay_finish(void *data, RenderState *state) {
     RenderPrimitiveOverlay *self = (RenderPrimitiveOverlay *)data;
+
+    if (self->color && self->color != default_color) {
+        free(self->color);
+    }
     
     Py_DECREF(self->facemask_top);
     Py_DECREF(self->white_color);