.NET WinForms图像艺术像素化代码问题求助

我在.NET WinForms中编写了生成输入图像艺术像素化效果的代码，但无法得到预期结果，预期效果与当前生成效果均已附图。以下是我的DrawShape方法代码：

private void DrawShape(Graphics g, Brush brush, int x, int y, int size)
{
    int halfSize = size / 2;
    int xOffset = chkOverlap.Checked ? -halfSize : 0;
    int yOffset = chkOverlap.Checked ? -halfSize : 0;

    if (chkCircle.Checked)
    {
        // Draw the outer circle
        g.FillEllipse(brush, x + xOffset, y + yOffset, size, size);

        // Draw the first inner circle (blue color)
        using (Brush innerBrush1 = new SolidBrush(Color.Blue))
        {
            int innerSize1 = size / 2;
            int innerX1 = x + halfSize - innerSize1 / 2 + xOffset;
            int innerY1 = y + halfSize - innerSize1 / 2 + yOffset;
            g.FillEllipse(innerBrush1, innerX1, innerY1, innerSize1, innerSize1);
        }

        // Draw the second inner circle (red color)
        using (Brush innerBrush2 = new SolidBrush(Color.Red))
        {
            int innerSize2 = size / 3;
            int innerX2 = x + halfSize - innerSize2 / 2 + xOffset;
            int innerY2 = y + halfSize - innerSize2 / 2 + yOffset;
            g.FillEllipse(innerBrush2, innerX2, innerY2, innerSize2, innerSize2);
        }
    }
    else if (chkSquare.Checked)
    {
        g.FillRectangle(brush, x + xOffset, y + yOffset, size, size);
    }
    else if (chkTriangle.Checked)
    {
        PointF[] trianglePoints = new PointF[]
        {
            new PointF(x + size / 2 + xOffset, y + yOffset),
            new PointF(x + xOffset, y + size + yOffset),
            new PointF(x + size + xOffset, y + size + yOffset)
        };
        g.FillPolygon(brush, trianglePoints);
    }
    else if (chkRectangle.Checked)
    {
        g.FillRectangle(brush, x + xOffset, y + yOffset, size * 2, size);
    }
}

我尝试过上述代码，但生成效果不符合预期，恳请协助解决。

内容的提问来源于stack exchange，提问作者vampire