Reverse operation of view.screen_coords

thomthom

@tig said:

If you get the view.camera, get its .eye and .target and change these points 'in tandem', then apply them to a new/updated camera etc then the view should 'pan'...
[I put that very simplistically but you ought to get the idea]
So with eye.x=eye.x+10 and target.x=target.x+10 ... it should pan the camera by 10 to the right etc...

He's trying to figure out how much he has to move the camera in order for it to shift by the size of the viewport.

TIG

How about https://developers.google.com/sketchup/docs/ourdoc/inputpoint#position ?

thomthom

@tig said:

How about https://developers.google.com/sketchup/docs/ourdoc/inputpoint#position ?

Doesn't that risk it snapping to nearby geometry? That's why I was thinking a raytest would be safest as it would not be affected by inference.

TIG

He can specify the view's inputpoint by using screen-coordinates (x,y) ?
And then get the inputpoint's position as a 3dPoint ??

That way he can get the screen width as with y at 0, and x at 0 and screen-width, gives two points - he can get the distance between them, then that's the amount to shunt the camera's eye/target across to pan a whole screen in the x-direction ?

TIG

This 'proof of concept' pans the whole screen to the right [in plan is easiest to see...]

def pan_whole_screen_to_the_right()
  model=Sketchup.active_model
  view=model.active_view
  ip0=view.inputpoint(0,0)
  ip1=view.inputpoint(view.vpwidth,0)
  p0=ip0.position
  p1=ip1.position
  dis=p0.distance(p1)
  cam=view.camera
  eye=cam.eye
  tar=cam.target
  upp=cam.up
  eye.x=eye.x+dis
  tar.x=tar.x+dis
  cam.set(eye,tar,upp)
end

Obviously you can make a more flexible method which could pan right/left and up/down as desired...

thomthom

@tig said:

He can specify the view's inputpoint by using screen-coordinates (x,y) ?
And then get the inputpoint's position as a 3dPoint ??

But my concern was that InputPoint will return a 3D point affected by inference, ie it snaps to mid points or something, based onthe 2D point.

TIG

I see the point.
Here's a fuller version that avoids that [can you think of a better way?]

def pan_whole_screen_to_the_right()
  model=Sketchup.active_model
  ents=model.entities
  ants=model.active_entities
  pants=ents.to_a+ants.to_a
  hidn=pants.uniq.find_all{|e|not e.hidden?}
  model.start_operation('pants')
  hidn.each{|e|e.hidden=true}
  hgeo=model.rendering_options["DrawHidden"]
  model.rendering_options["DrawHidden"]=false
  view=model.active_view
  ip0=view.inputpoint(0,0)
  ip1=view.inputpoint(view.vpwidth,0)
  p0=ip0.position
  p1=ip1.position
  dis=p0.distance(p1)
  cam=view.camera
  eye=cam.eye
  tar=cam.target
  upp=cam.up
  eye.x=eye.x+dis
  tar.x=tar.x+dis
  cam.set(eye,tar,upp)
  hidn.each{|e|e.hidden=false}
  model.rendering_options["DrawHidden"]=hgeo
  model.commit_operation
end

thomthom

@tig said:

Here's a fuller version that avoids that [can you think of a better way?] [code]def pan_whole_screen_to_the_right()

http://forums.sketchucation.com/viewtopic.php?f=180&t=44290#p394956

TIG

Therefore we can substitute
p0=view.pickray(0,0)[0] p1=view.pickray(view.vpwidth,0)[0]
and get a simpler method because the ray's point doesn't get influenced by inferences and is made on the picture-plane, as it were...

def pan_whole_screen_to_the_right()
  model=Sketchup.active_model
  view=model.active_view
  p0=view.pickray(0,0)[0]
  p1=view.pickray(view.vpwidth,0)[0]
  dis=p0.distance(p1)
  cam=view.camera
  eye=cam.eye
  tar=cam.target
  upp=cam.up
  eye.x=eye.x+dis
  tar.x=tar.x+dis
  cam.set(eye,tar,upp)
end

thomthom

Ah, yes! Of course - no need to pick anything. I forgot that the ray contained a point that could be used directly.

TIG

Two brains are better than one [at least our combined IQs add up to around the average!!]

thomthom

I've already determined that my brain is on timeshare lease...

jpark

TIG and thomthom,

Do you guys ever sleep!!??
You gave me a plenty of assignment for the weekend; to digest all that you posted.

For your info, I am attempting to model a 'plan viewer' for blueprints which will become framework for architectural components

Thanks guys

John

thomthom

"Sl-eep"..?

jpark

Just finished reading up on view.pickray method and ran TIG's sample code. At first glance it should have worked but does not. In executing each line, I find that p0 and p1 return same value as camera eye position. See Ruby Console responses below:

p0=view.pickray(0,0)[0] Point3d(3255.11, 1479.16, 8761.61) p1=view.pickray(view.vpwidth,0)[0] Point3d(3255.11, 1479.16, 8761.61) p2=view.pickray(0,view.vpheight)[0] Point3d(3255.11, 1479.16, 8761.61) p3=view.pickray(view.vpwidth,view.vpheight)[0] Point3d(3255.11, 1479.16, 8761.61) cam=Sketchup.active_model.active_view.camera #<Sketchup::Camera:0x7ce5de0> cam.eye Point3d(3255.11, 1479.16, 8761.61) cam.target Point3d(3255.11, 1479.16, 127.281) cam.up Vector3d(0, 1, 0)

How could this be? I thought I understood pickray method but NOT

Off the topic note: where can I find instruction on how to annotate posting w/ codes, images, smiles, etc ...

John

TIG

I added some 'ruby' tags to make it clearer...

I hope this is not ALL of the code...
Have you set the view and so on earlier ?
IF so... you don't use
cam=Sketchup.active_model.active_view.camera
but
cam=view.camera
???
My code is a working example.......

Dan Rathbun

@jpark said:

Off the topic note: where can I find instruction on how to annotate posting w/ codes, images, smiles, etc ...

There is a "hard to find" link on each message "POST A REPLY" page, in the right column, beneath the "Smilies" list.

Notice how the line "BBCode is ON" has a link ??

It leads you to a user guide for the code tags.

Most of these usable tags have toolbar button "inserters" already set up for you to use. You just click the button, it inserts the tag. and positions the cursor between the tags so you can type text (or paste text,) into them.

jpark

@dan rathbun said:

There is a "hard to find" link on each message "POST A REPLY" page, in the right column, beneath the "Smilies" list.

Now I'm enlightened Thanks Dan

@tig said:

I hope this is not ALL of the code...

No this is an output of individual Ruby Console execution. This is my attempt to debug each line of your sample code to check each variable's current value. Programming is my hobby and I just picked up Sketchup and Ruby couple of months ago so I have a lot to learn.

Back to pickray method - All screen postions (ie p0, p1, p2, and p3) return different value yet pickray method of these points return identical 3D point as camera eye position but with different vector. How come?

John

thomthom

eh.. TIG, I think we both did a brain-fart. We have to do a raytest - otherwise the ray will return a point which is based on the camera eye... because all pickray origin from the camera eye.

thomthom

Though, at 2:30 it's hard to process these thigns...