How to Zoom and Resize to a Component

Replies to This Discussion

Permalink Reply by Steve Lewis on January 24, 2012 at 10:47pm

Come on, anyone?

Permalink Reply by David Rutten on January 25, 2012 at 1:30am

Have a look at Grasshopper.GUI.Canvas.GH_NamedView class. It has several constructors, one of which is bound to suit you. When you're done, call SetToViewport().

--

David Rutten

david@mcneel.com

Poprad, Slovakia

Permalink Reply by Steve Lewis on January 25, 2012 at 1:37am

Thanks for the reply.

 

I think i sorted it, seems to work fine now, this is what i did:

 

Dim sysPoint As System.Drawing.Point

sysPoint.X = CInt(CInt(ghObject.Attributes.Bounds.Right - ghObject.Attributes.Bounds.Left) / 2) + CInt(ghObject.Attributes.Bounds.Left)

sysPoint.Y = CInt(CInt(ghObject.Attributes.Bounds.Top - ghObject.Attributes.Bounds.Bottom) / 2) + CInt(ghObject.Attributes.Bounds.Bottom) ghCanvas.Viewport.MidPoint = sysPoint ghCanvas.Refresh()

 

Is there a better way?

 

 

Permalink Reply by Steve Lewis on February 16, 2012 at 12:42am

Hi david, im trying to avoid using events. Im still ahving trouble rescaling to the corrcet zoom factor.

 

I have selected my component on the canvas and i have set the viewport to teh center of the component.

however, i just cannot find the correct scale factor to use, see the following:

  ghCanvas.Viewport.Zoom(True) = (ghCanvas.Viewport.VisibleRegion.Width / ghDocument.BoundingBox(True).Width) 

also tried

  Dim sysRectangleExtent As System.Drawing.RectangleF = ghDocument.BoundingBox(False) 

ghCanvas.Viewport.Zoom(True) = sysRectangleExtent.Width / ghDocument.BoundingBox(True).Width 

I dont really understand the maths behind the value for Zoom,

thanks

Steve

Permalink Reply by David Rutten on February 16, 2012 at 2:18am

Hi Steve,

zoom is the normalised value of the percentage you see in the GUI. Basically, it's the scaling factor applied to the display. So a zoom of 1.0 is pixel-per-pixel perfect, a zoom factor of 0.5 (50%) will make everything look half as big, a zoom factor of 3.0 (300%) will make everything look 3 times bigger.

The code I use in the Variable Parameter tip looks like this:

Dim box As RectangleF = Attributes.Bounds
Dim pt As New PointF(box.X + 0.5F * box.Width, _

                               box.Top + 0.5F * box.Height)
Dim view As New GH_NamedView("zui_zoom", pt, _

                                                10.0F, GH_NamedViewType.center)

view.SetToViewport(canvas, 1200)

I use a fixed zoom factor of 10.0 but you'll need to compute a variable zoom level each time. Basically, the zoom level you want it the factor you need to multiply the Attributes.Bounds with in order to make them as big as the viewport.ScreenPort So if the ScreenPort is 950 pixels wide and 720 pixels high and the Bounds of the attributes are 55 pixels wide and 75 pixels high, the zoom factor to make the width and height fit exactly would be:

Dim zoomW As Single = Convert.ToSingle(950/55)

Dim zoomH As Single = Convert.ToSingle(720/75)

Dim zoom As Single = Math.Min(zoomW, zoomH)

Where zoom is the lowest of the two. I hope my math isn't wrong, I didn't test this and only just woke up... But that's the basic idea.

--

David Rutten

david@mcneel.com

Poprad, Slovakia

Permalink Reply by Steve Lewis on February 16, 2012 at 11:18am

Thank you David, I think this will help tremendously

 

Steve

Permalink Reply by Steve Lewis on March 6, 2012 at 11:06pm

David, awesome, your code worked, heres my final code.....

 

Dim sysMidPoint As System.Drawing.Point Dim sysTargetPoint As System.Drawing.Point sysTargetPoint.X = CInt(ghDocument.BoundingBox(True).Location.X) sysTargetPoint.Y = CInt(ghDocument.BoundingBox(True).Location.Y) sysMidPoint.X = CInt(sysTargetPoint.X + (ghDocument.BoundingBox(True).Width / 2)) sysMidPoint.Y = CInt(sysTargetPoint.Y + (ghDocument.BoundingBox(True).Height / 2)) Dim sZoomW As Single = Convert.ToSingle(ghCanvas.Viewport.ScreenPort.Width / ghDocument.BoundingBox(True).Width) Dim sZoomH As Single = Convert.ToSingle(ghCanvas.Viewport.ScreenPort.Height / ghDocument.BoundingBox(True).Height) Dim sZoom As Single = Math.Min(sZoomW, sZoomH) Dim ghNamedView As New Grasshopper.GUI.Canvas.GH_NamedView ghNamedView.Point = sysMidPoint ghNamedView.Zoom = sZoom ghNamedView.Type = Grasshopper.GUI.Canvas.GH_NamedViewType.center ghNamedView.SetToViewport(ghCanvas, 1200) ghCanvas.Refresh()