Question

我有一个图片框。在图片框中，我使用以下方式画线：

gfx.DrawLine(nPen, line.xBegin, line.yBegin, line.xEnd, line.yEnd);

line是一个包含行开头和结束值的对象。

我在那个图片框上画了10行。我的mouse_Wheel监听器包含代码：

gfx.TranslateTransform((panelpreview.Width) / 2, (panelpreview.Height) / 2);
gfx.ScaleTransform(imageScale, imageScale);
gfx.TranslateTransform(-(panelpreview.Width) / 2, -(panelpreview.Height) / 2);

目前我正试图通过以下方式移动：

    private void panelPreview_MouseDown(object sender, MouseEventArgs e)
    {
        if (e.Button == System.Windows.Forms.MouseButtons.Left)
        {
            checkLinesIntersection(e.Location); //checks if e.Location intersects with the line
            panelPreview.MouseUp += new MouseEventHandler(panelPreview_MouseUpLine);
            panelPreview.MouseMove += new MouseEventHandler(panelPreview_MouseMoveLine);
        }
    }

    void panelPreview_MouseMoveLine(object sender, MouseEventArgs e)
    {
        if (_Leading.movable)
            newFont.Leading = e.Y - (_base.yBegin + newFont._descenderHeight);

        if (_xHeight.movable)
            if (_base.yBegin - e.Y >= 0)
                newFont.xHeight = _base.yBegin - e.Y;

        if (_capHeight.movable)
            if (_base.yBegin - e.Y >= 0)
                newFont.capHeight = _base.yBegin - e.Y;

        if (_ascenderHeight.movable)
            if (_base.yBegin - e.Y >= 0)
                newFont.ascenderHeight = _base.yBegin - e.Y;

        if (_descenderHeight.movable)
            if (e.Y - _base.yBegin >= 0)
                newFont.descenderHeight = e.Y - _base.yBegin;

        UpdatePreviewWindow();
    }

    void panelPreview_MouseUpLine(object sender, MouseEventArgs e)
    {
        panelPreview.MouseMove -= new MouseEventHandler(panelPreview_MouseMoveLine);
        panelPreview.MouseUp -= new MouseEventHandler(panelPreview_MouseUpLine);
    }

问题是，在放大后，即使在视觉上我按下线，但它没有反应它应该的方式。

    public void checkLinesIntersection(Point mouseLocation)
    {
        lineIntersects(_Leading, mouseLocation);
        lineIntersects(_xHeight, mouseLocation);
    }

    private void lineIntersects(nLine line, Point mouseLocation)
    {
        if (mouseLocation.X >= line.xBegin && mouseLocation.X <= line.xEnd)
            if (mouseLocation.Y >= line.yBegin || mouseLocation.Y + 2 >= line.yBegin)
                if (mouseLocation.Y <= line.yEnd || mouseLocation.Y - 2 <= line.yEnd)
                    switch (line.sName)
                    {
                        case "xHeight":
                            newFont.selectedLine = nFont.Lines._xHeight;
                            break;
                        default:
                            break;
                    }
    }

Answer 1

原来如此！在这个工具上工作了一段时间后，我改变了方法并使用XNA来处理图形（绘图，缩放，移动绘图对象）。对我有很大帮助的是在XNA和Camera中使用Matrix进行转换。无论如何！我不会发布我的XNA解决方案来处理这个问题但是通过使用XNA我找到了在WinForms中处理它的方法。

float Zoom = 1f;
Microsoft.Xna.Framework.Rectangle mouseRect;
Matrix inverse;

void TAB_PICTURE_BOX_MouseWheel(object sender, MouseEventArgs e)
    {
        try
        {
            if (e.Delta > 0)
            {
                Zoom+= .1f;
            }
            if (e.Delta < 0)
            {
                Zoom -= .1f;
            }

            gfx.ResetTransform();
            gfx.TranslateTransform((Width + img.Width) / 2, (Height - img.Height) / 2);
            gfx.ScaleTransform(Zoom, Zoom);
            gfx.TranslateTransform(-(Width + img.Width) / 2, -(Height - img.Height) / 2);      
                getInversePosition(e);
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex.Message);
        }
    }

最后触摸getInversePosition(e);方法：

 private void getInversePosition(MouseEventArgs e)
    {
        Matrix matrix = Matrix.CreateTranslation(new Vector3(-(Width + img.Width) / 2, -(Height - img.Height) / 2, 0)) *
                  Matrix.CreateScale(new Vector3(Zoom, Zoom, 1)) *
                  Matrix.CreateTranslation(new Vector3((Width + img.Width) / 2, (Height - img.Height) / 2, 0));

        inverse = Matrix.Invert(matrix);
        Vector2 mousePosition = Vector2.Transform(new Vector2(e.X, e.Y), inverse);
        mouseRect = new Microsoft.Xna.Framework.Rectangle((int)mousePosition.X, (int)mousePosition.Y, 1, 1);
    }

我确信有一种方法可以在没有XNA参与的情况下处理它但在我的场景中XNA完成了工作。

如何在GDI +中移动缩放行

1 个答案: