Initial data commit

Task/Draw-a-sphere/Delphi/draw-a-sphere.delphi

@@ -0,0 +1,70 @@
+program DrawASphere;
+
+{$APPTYPE CONSOLE}
+
+uses
+  SysUtils,
+  Math;
+
+type
+  TDouble3  = array[0..2] of Double;
+  TChar10 = array[0..9] of Char;
+
+var
+  shades: TChar10 = ('.', ':', '!', '*', 'o', 'e', '&', '#', '%', '@');
+  light: TDouble3 = (30, 30, -50 );
+
+  procedure normalize(var v: TDouble3);
+  var
+    len: Double;
+  begin
+    len:= sqrt(v[0]*v[0] + v[1]*v[1] + v[2]*v[2]);
+    v[0] := v[0] / len;
+    v[1] := v[1] / len;
+    v[2] := v[2] / len;
+  end;
+
+  function dot(x, y: TDouble3): Double;
+  begin
+    Result:= x[0]*y[0] + x[1]*y[1] + x[2]*y[2];
+    Result:= IfThen(Result < 0, -Result, 0 );
+  end;
+
+  procedure drawSphere(R, k, ambient: Double);
+  var
+    vec: TDouble3;
+    x, y, b: Double;
+    i, j,
+    intensity: Integer;
+  begin
+    for i:= Floor(-R) to Ceil(R) do
+    begin
+      x := i + 0.5;
+      for j:= Floor(-2*R) to Ceil(2 * R) do
+      begin
+        y:= j / 2 + 0.5;
+        if(x * x + y * y <= R * R) then
+        begin
+          vec[0]:= x;
+          vec[1]:= y;
+          vec[2]:= sqrt(R * R - x * x - y * y);
+          normalize(vec);
+          b:= Power(dot(light, vec), k) + ambient;
+          intensity:= IfThen(b <= 0,
+                             Length(shades) - 2,
+                             Trunc(max( (1 - b) * (Length(shades) - 1), 0 )));
+          Write(shades[intensity]);
+        end
+        else
+          Write(' ');
+      end;
+      Writeln;
+    end;
+  end;
+
+begin
+  normalize(light);
+  drawSphere(19, 4, 0.1);
+  drawSphere(10, 2, 0.4);
+  Readln;
+end.