sotextpit

[moebius.git] / graphics.cc

diff --git a/graphics.cc b/graphics.cc
index ae1659e97b69b4cae05e1043d5ff0198345bac3c..605d8834535925b2bcc85203e4b379b694fa357d 100644 (file)
--- a/graphics.cc
+++ b/graphics.cc
@@ -12,6 +12,7 @@
 #include "library.hh"
 #include "graphics.hh"
 #include "output.hh"
+#include "parameter.hh"
 
 static int checkneededline(Onscreen a, Onscreen b) {
   double xd= a.x - b.x;
@@ -20,6 +21,10 @@ static int checkneededline(Onscreen a, Onscreen b) {
   return n>0 ? n : 1;
 }
 
+static Parameter<double>
+sotextpit("sotextpit", "Pitch of solid texture (0: grid mode)",
+         0., 1., 0., 1000.);
+
 void Cell::display(Output& o) {
   int nn[4];
   int totalnn= 0;
@@ -30,14 +35,28 @@ void Cell::display(Output& o) {
   }
   Point *array= new Point[totalnn];
   Point *inarrayp= array;
+  Point mean(0,0,0);
   for (i=0; i<4; i++) {
     for (int a=0; a<nn[i]; a++) {
       double fp= (double)a         / nn[i];
       double fn= (double)(nn[i]-a) / nn[i];
       *inarrayp++= p[i]*fn + p[(i+1)&3]*fp;
     }
+    mean = mean + p[i];
+  }
+  mean = mean * 0.25;
+  Output::Colour colour= Output::grid;
+  if (sotextpit > 0) {
+    bool white= false;
+    for (i=0; i<3; i++) {
+      double intpartdummy;
+      double remainder= modf(mean[i] / sotextpit, &intpartdummy);
+      if (remainder >= 0.5 || (remainder >= -0.5 && remainder < 0.0))
+       white= !white;
+    }
+    colour= white ? Output::solidwhite : Output::solidblack;
   }
-  o.drawcell(array,totalnn);
+  o.drawcell(array,totalnn,colour);
   delete[] array;
 }