Re: [Freeciv-Dev] grid lines

[Vasco Alexandre Da Silva Costa <vasc@xxxxxxxxxxxxxxxxxxxxx>]

On Wed, 17 Mar 1999, Trent Piepho wrote:

> I though of several different ways of making grid lines, but I'm not sure
> which one I like best.
> 
> So here is a patch which demonstrates them.  It's not finished, it doesn't let
> you turn them on or off.  Every time you scroll the map, the line type will
> change.  First it's dashed black lines, then solid xor lines, dashed xor
> lines, and finally solid black lines.
> 
> I'm thinking either dashed black lines or solid xor lines.
> 

+    for(x=tile_x; x<=tile_x+width; x++)
+      XDrawLine(display, map_canvas_store, civ_gc, 
+                x*NORMAL_TILE_WIDTH, tile_y*NORMAL_TILE_HEIGHT,
+               x*NORMAL_TILE_WIDTH, (tile_y+height)*NORMAL_TILE_HEIGHT);
+    for(y=tile_y; y<=tile_y+height; y++)
+      XDrawLine(display, map_canvas_store, civ_gc, 
+                tile_x*NORMAL_TILE_WIDTH, y*NORMAL_TILE_HEIGHT,
+               (tile_x+width)*NORMAL_TILE_WIDTH, y*NORMAL_TILE_HEIGHT);

Why are you doing that x*NORMAL_TILE_WIDTH stuff over and over again?
Most things can be precalculated...

    n_tile_x *= NORMAL_TILE_WIDTH;
    n_width *= NORMAL_TILE_WIDTH;

    n_tile_y *= NORMAL_TILE_HEIGHT;
    n_height *= NORMAL_TILE_HEIGHT;

    for(x=tile_x; x<=n_tile_x+n_width; x+=NORMAL_TILE_WIDTH)
      XDrawLine(display, map_canvas_store, civ_gc, 
                x, n_tile_y,
                x, n_tile_y+n_height);

    for(y=tile_y; y<=n_tile_y+n_height; y+=NORMAL_TILE_HEIGHT)
      XDrawLine(display, map_canvas_store, civ_gc, 
                n_tile_x, y,
                n_tile_x+n_width, y);

---
Vasco Alexandre da Silva Costa, student @ Instituto Superior Tecnico,
Technical University of Lisbon - Software & Computer Engineering