zoomedit: Added grid.

draw.c

@@ -1,6 +1,7 @@
 #include "draw.h"
 #include "level.h"
 #include "geometry.h"
+#include <math.h>
 #include <gtk/gtk.h>
 #include <cairo/cairo.h>
 
@@ -9,7 +10,39 @@ static double scale = 100.0;
 static double xTranslate = 0.0, yTranslate = 0.0;
 
 
-static void room2path(cairo_t *cr, ROOM *room, RECTANGLE *rect) {
+static void drawGrid(cairo_t *cr, const RECTANGLE *rect) {
+  double depth = log10(scale)-0.75;
+  double depth2 = floor(depth);
+  double step = pow(0.1, depth2);
+  double x;
+  int i;
+  
+  cairo_set_source_rgb(cr, 0.2*(depth-depth2), 0.2*(depth-depth2), 0.2*(depth-depth2));
+  
+  for(i = 0; i < 3; i++) {
+    for(x = rect->x - fmod(rect->x, step); x <= rect->x+rect->width; x+=step) {
+      cairo_move_to(cr, x, rect->y);
+      cairo_line_to(cr, x, rect->y+rect->height);
+      
+      cairo_stroke(cr);
+    }
+    
+    for(x = rect->y - fmod(rect->y, step); x <= rect->y+rect->height; x+=step) {
+      cairo_move_to(cr, rect->x, x);
+      cairo_line_to(cr, rect->x+rect->width, x);
+      
+      cairo_stroke(cr);
+    }
+    
+    step *= 10;
+    if(i == 0 && 0.2*(depth-depth2+1) < 0.3)
+      cairo_set_source_rgb(cr, 0.2*(depth-depth2+1), 0.2*(depth-depth2+1), 0.2*(depth-depth2+1));
+    else
+      cairo_set_source_rgb(cr, 0.3, 0.3, 0.3);
+  }
+}
+
+static void room2path(cairo_t *cr, const ROOM *room, const RECTANGLE *rect) {
   int i;
   ROOM room2 = {0, NULL};
   
@@ -58,6 +91,8 @@ gboolean drawTopView(GtkWidget *widget, GdkEventExpose *event, gpointer data) {
   cairo_set_line_width(cr, 1.0/scale);
   cairo_set_line_join(cr, CAIRO_LINE_JOIN_MITER);
   
+  drawGrid(cr, &rect);
+  
   for(i = 0; i < lvl.nRooms; i++)
     room2path(cr, &lvl.rooms[i], &rect);