simplify Meter loop

* Use MIN() and MAX() to make sure values are inside bounds. This should
  fix an issue where Meters were missing dots at the bottom.
* Remove variable 'level' and calculate on the fly.

Meter.c

@@ -376,23 +376,17 @@ static void GraphMeterMode_draw(Meter* this, int x, int y, int w) {
    
    for (int i = nValues - (w*2) + 2, k = 0; i < nValues; i+=2, k++) {
       const double dot = (1.0 / (pixperrow * 4));
-      int v1 = data->values[i] / dot;
-      int v2 = data->values[i+1] / dot;
-      
-      if (v1 == 0) v1 = 1;
-      if (v2 == 0) v2 = 1;
-      
-      int level = pixperrow * 3;
+      int v1 = MIN(pixperrow * 4, MAX(1, data->values[i] / dot));
+      int v2 = MIN(pixperrow * 4, MAX(1, data->values[i+1] / dot));
+
       int colorIdx = GRAPH_1;
       for (int line = 0; line < 4; line++) {
-         
-         int line1 = MIN(pixperrow, MAX(0, v1 - level));
-         int line2 = MIN(pixperrow, MAX(0, v2 - level));
- 
+         int line1 = MIN(pixperrow, MAX(0, v1 - (pixperrow * (3 - line))));
+         int line2 = MIN(pixperrow, MAX(0, v2 - (pixperrow * (3 - line))));
+
          attrset(CRT_colors[colorIdx]);
          mvaddstr(y+line, x+k, GraphMeterMode_dots[line1 * (pixperrow + 1) + line2]);
          colorIdx = GRAPH_2;
-         level -= pixperrow;
       }
    }
    attrset(CRT_colors[RESET_COLOR]);