たとえば、50x50 ピクセルなど、より大きなクワッドで小さな 2x2 ピクセル テクスチャを繰り返したいと考えています。
頂点を設定 -
float X = 100, Y = 100, Width = 50, Height = 50;
float TextureLeft = 0, TextureTop = 0, TextureRight = 25, TextureBottom = 25;
Vertices[0].x = X;
Vertices[0].y = Y + Height;
Vertices[0].z = 0;
Vertices[0].rhw = 1;
Vertices[0].tu = TextureLeft;
Vertices[0].tv = TextureBottom;
Vertices[1].x = X;
Vertices[1].y = Y;
Vertices[1].z = 0;
Vertices[1].rhw = 1;
Vertices[1].tu = TextureLeft;
Vertices[1].tv = TextureTop;
Vertices[2].x = X + Width;
Vertices[2].y = Y;
Vertices[2].z = 0;
Vertices[2].rhw = 1;
Vertices[2].tu = TextureRight;
Vertices[2].tv = TextureTop;
Vertices[3].x = X;
Vertices[3].y = Y + Height;
Vertices[3].z = 0;
Vertices[3].rhw = 1;
Vertices[3].tu = TextureLeft;
Vertices[3].tv = TextureBottom;
Vertices[4].x = X + Width;
Vertices[4].y = Y;
Vertices[4].z = 0;
Vertices[4].rhw = 1;
Vertices[4].tu = TextureRight;
Vertices[4].tv = TextureTop;
Vertices[5].x = X + Width;
Vertices[5].y = Y + Height;
Vertices[5].z = 0;
Vertices[5].rhw = 1;
Vertices[5].tu = TextureRight;
Vertices[5].tv = TextureBottom;
描く -
DrawPrimitive(D3DPT_TRIANGLELIST, 0, 6);
問題は、三角形間のエッジの「グリッチ」です。おそらく頂点座標が間違っているためであり、クワッド境界の「グリッチ」も原因です。
元のテクスチャ - http://i.imgur.com/tNqYePs.png