Feature Reference - The Game Maker's Companion: Game Development - page 359

1: {
2: if ( view_current == 0 )
3: {
4: draw_set_font(fnt_score);
5: draw_set_color(c_white);
6: draw_text(view_xview[0]+480,
7: view_yview[0]+20,'Score: '+string(score));
8: dx1 = view_xview[0]+view_xport[1];
9: dy1 = view_yview[0]+view_yport[1];
10: dx2 = dx1+view_wport[1];
11: dy2 = dy1+view_hport[1];
12: draw_rectangle(dx1-1,dy1-1,dx2+1,dy2+1,true);
13: }
14: }

This script takes some explaining. The entire room is redrawn once for each view,
which actually means that all draw events are executed twice: once for view 0 and once
for view 1. The variable view_current keeps track of which view is currently being
drawn. We check it in line 2 so we can draw the score only in view 0 (lines 4-7).
Lines 8-12 draw a rectangle around view 1, which must also be done in view 0. In
fact, just like the score, the rectangle must follow view 0 around (which, in turn, follows
the spaceship) to keep it on the screen. The variables dx1 , dy1 , dx2 , and dy2 are used to
calculate the positions in the room between which the rectangle must be drawn so that
it always appears in the top-left corner of view 0, which is our main view. Line 12
finally draws it, making it a pixel larger than view 1 on each side.

Result: Reference/Result/mini_map1.gmk

You'll have noticed that making the room ten times smaller in the mini-map view doesn't
make it any easier to see what's going on in the mini-map. It sometimes makes sense to map only
a portion of the room that is only somewhat larger than what is actually shown in the main view.

Changing the Mini-Map to View Only Part of the Room
1. Open test_room again, select the views tab, and click View 1 . Because we're only going

to show part of the room, we'll have to make it follow the spaceship around. Set Object
following to obj_spaceship .

2. First, let's decide how large the viewed area is. Once again, it is a good idea to set this

in proportion to the port of the view. To size things up, halve the values in View in
room to 800 for width and 600 for height. It shouldn't be any smaller than this, because
the main view is 640x480.

Let's try to center the spaceship in the mini-map view as well. Set Hbor to 400 and
Vbor to 300 —this sets the horizontal and vertical borders around the spaceship to
exactly half the size of the view in the room set previously, which centers the spaceship
in the mini-map.

3.

Result: Reference/Result/mini_map2.gmk