Create your own sky and ground?

JClements

Jim, thanks for the reply.

Maybe SU7 will add a dialog (similar to the watermark dialog) to use a bitmap for the sky.

If they are really generous maybe a hook into to Google Earth's constellations for nightime scenes ... wouldn' that be fun.

AdamB

Towards the end it shows a complete skybox all done within Sketchup.

http://uk.youtube.com/watch?v=GPk035_EtFs

JClements

Very cool!

Did you have to use a special photo or technique so it would map seamlessly? I am assuming the photo is mapped to the inside of a cylinder.

AdamB

@jclements said:

Very cool!

Did you have to use a special photo or technique so it would map seamlessly? I am assuming the photo is mapped to the inside of a cylinder.

No, its a technique commonly used in video games called a "skybox". There are 6 photos (left,right,back,front,up,down) mapped to 6 faces of a inverted cube. If you google "skybox" you should find some examples. In the plugin you just choose the file you want in the preferences.

Adam

Alan Fraser

Skyboxes don't work at all well in SU...the corners are way too obvious. Skydomes are a much better alternative, or you can even go with simple cylinders if you don't look up too much. I have created a number of skydomes for SU. There is a quick example of one here.
The quality of the YouTube video is pretty awful, but it gives a rough idea of the kind of immersive environment that is possible in SU.

gata

It's possible to remap a dome/globe/sphere with your own image http://www.barnabu.co.uk/sketchup-skydome/

AdamB

@alan fraser said:

Skyboxes don't work at all well in SU...the corners are way too obvious. Skydomes are a much better alternative, or you can even go with simple cylinders if you don't look up too much. I have created a number of skydomes for SU. There is a quick example of one here.
The quality of the YouTube video is pretty awful, but it gives a rough idea of the kind of immersive environment that is possible in SU.

Well if you do it "right" you cannot see any seams using a skybox. (Watch the video link I posted to confirm this)

Adam

JClements

Adam,

Is the sky box a feature built into your app or are you using another application and then importing the result into SU?

Alan Fraser

Texture Maker will generate a cgi landscape and sky and export it in a variety of formats...including a skybox. Screenshot and result attached below.
Sky boxes are used extensively in games and work very well. They can be used well in SU, as Adam says, but only really from a very fixed viewpoint....that being the centre of the cube.
Games get around this by locking the skybox to the viewer. As you move through a first person perspective shoot-em-up the skybox moves with you, so always appears in the correct perspective and always infinitely distant. This obviously isn't the case in SU.
I realise this thread has drifted slightly away from Ruby, but there's a challenge for somebody.
Skyboxes can work well in SU, but generally only if you move a few feet...or catch a glimpse out of a window, not up and down streets. Of course you can make them really huge, so that any novement by the viewer is very slight in comparison...but then you get clipping problems.

The simplest solution is simply to map a panoramic image around a cylinder. Here is a very old thread from the old forum, now transferred to Google Groups. So old, in fact, that it predates SU's ability to map around cylinders, so I had to do it by slicing the image into sections...but the resulting skps still work ok for most situations.

AdamB

I initially implemented skyboxes in pure Ruby in SU.


# skybox functionality
class MyViewObserver <  Sketchup;;ViewObserver

	def initialize(stub)

		..  build a definition using 'stub' as filepath

		skybox = Sketchup.active_model.definitions[dname]

		@skybox = Sketchup.active_model.entities.add_instance skybox, Geom;;Transformation.new
		@skybox.locked= true
	end

 	def onViewChanged (view)
		@skybox.locked= false
		@skybox.move! view.camera.eye
		@skybox.locked= true
	end

	def remove
		@skybox.locked= false
		Sketchup.active_model.entities.erase_entities @skybox
	end
end

def add_skybox
	$skybox = MyViewObserver.new("~projects/Ruby/skybox/space1")
	Sketchup.active_model.active_view.add_observer($skybox)
end

ie Sketchup will move the skybox along with your camera. Works OK - only let down by SU crazily aggressive bounds on Z when it draws.

Adam

@alan fraser said:

Texture Maker will generate a cgi landscape and sky and export it in a variety of formats...including a skybox. Screenshot and result attached below.
Sky boxes are used extensively in games and work very well. They can be used well in SU, as Adam says, but only really from a very fixed viewpoint....that being the centre of the cube.
Games get around this by locking the skybox to the viewer. As you move through a first person perspective shoot-em-up the skybox moves with you, so always appears in the correct perspective and always infinitely distant. This obviously isn't the case in SU.
I realise this thread has drifted slightly away from Ruby, but there's a challenge for somebody.
Skyboxes can work well in SU, but generally only if you move a few feet...or catch a glimpse out of a window, not up and down streets. Of course you can make them really huge, so that any novement by the viewer is very slight in comparison...but then you get clipping problems.

The simplest solution is simply to map a panoramic image around a cylinder. Here is a very old thread from the old forum, now transferred to Google Groups. So old, in fact, that it predates SU's ability to map around cylinders, so I had to do it by slicing the image into sections...but the resulting skps still work ok for most situations.