アンチエイリアス（三角形の描画）

function triangle1

try

  AssertOpenGL

  ListenChar(2);

  %myKeyCheck;

  screenNumber = max(Screen('Screens'));

  [win, rect] = Screen('OpenWindow', screenNumber, 0, [10 50 750 550]);

  %三角形の頂点の座標

  apex = [0, 100, 100, 300, 300, 0;

            0, 200, 200, 50,  50,  0];

  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

  %パターン１

  % シンプルに三角形を描く

  Screen('DrawLines', win, apex, [], [255, 255, 255]);

  % 線分の太さを変える

  %Screen('DrawLines', win, apex, [6, 4, 2], [255, 255, 255]);

  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

  %パターン２

  % 頂点の座標を、画面中央が(0, 0)になるようにシフトさせる。

  %[center(1), center(2)] = RectCenter(rect);

  %Screen('DrawLines', win, apex, [], [255, 255, 255], center);

  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

  %パターン３

  % ３本の線分の色を変える

  %   １本目：白から赤、２本目：白から緑、３本目：白から青）

  %colvect = [255, 255, 255, 0,   255, 0;

  %           255, 0,   255, 255, 255, 0;

  %           255, 0,   255, 0,   255, 255];

  %Screen('DrawLines', win, apex, 2, colvect);

  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

  %パターン４

  % 三角形の辺を滑らかに描画する

  % 線分の太さが１のだと点線のように描画されてしまうことがある。

  %[center(1), center(2)] = RectCenter(rect);

  %Screen('BlendFunction', win, GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

  %Screen('DrawLines', win, apex, 2, [255, 255, 255], center, 1);

  Screen('Flip', win);

  KbWait;

  sca;

  ListenChar(0);

catch

  sca;

  ListenChar(0);

end