topic Re: Coloring of shape edges using CGA in ArcGIS CityEngine Questions

Coloring of shape edges using CGA

TessOldemeyer — Tue, 15 Sep 2015 17:57:32 GMT

I am trying to color edges (border and interior) of a planar shape layer (see screenshot) in CE using CGA. Ultimately, it would be great if colors could be chosen for the background (faces?) color as well as the outlines (edges?). I have been looking into the comp(Operation) option to select out the edges and color them. If I use:

set(material.opacity, Transparency)

color (...)

...then I can change the color/transparency of the entire shape, but the individual shape outlines are not visible and do not have a distinct color when I export the models as .3ws. I would like to be able to designate colors for both the outline and shape in CE prior to the export. Any suggestions would be very helpful as I am new to CE/CGA.

I have attached my current CGA code as well as a snip of the layer I am working with.

Thanks!

version "2015.1"

attr Fill_Color = "#FFFFF"

attr Outline_Color = "#000000"

attr Transparency = 0.9

@StartRule

Shape -->

set(material.opacity, Transparency)

comp(e) {all: color(Outline_Color)

}

comp(f) {all: color(Fill_Color)

}

Re: Coloring of shape edges using CGA

Anonymous User — Tue, 15 Sep 2015 18:18:21 GMT

Try using the CGA operation called offset, together with comp. Send individual faces to a rule like this:

AddOutline -->

offset(-0.02) # thickness of your border. Negative value offsets inwards.

comp( f ) {border: color(myBorderColor) MyBorder. | inside: MyInside.}

Chris

Re: Coloring of shape edges using CGA

TessOldemeyer — Tue, 15 Sep 2015 19:19:13 GMT

Thank you so much for your help! I was able to get the outlines using:

version "2015.1"

attr Fill_Color = "#FFF80"

attr Outline_Color = "#000000"

attr Transparency = 0.9

@StartRule

AddOutline -->

offset(-0.5) # thickness of your border. Negative value offsets inwards.

comp( f ) {border: color(Outline_Color) MyBorder. | inside: MyInside.}

Shape -->

set(material.opacity, Transparency)

color(Fill_Color)

Any ideas on how to get the fill color to show up?

Thanks again,

Tess

Re: Coloring of shape edges using CGA

Anonymous User — Tue, 15 Sep 2015 19:26:27 GMT

This line has a couple of placeholders:

comp( f ) {border: color(Outline_Color) MyBorder. | inside: MyInside.}

Your rule called Shape is not getting called anywhere, so use the "inside" selector to run your rule "Shape" from there....

comp( f ) {border: color(Outline_Color) MyBorder. | inside: Shape}

Re: Coloring of shape edges using CGA

TessOldemeyer — Tue, 15 Sep 2015 21:24:09 GMT

That seems to do the trick. Thanks a ton!

The fill color is just patchy.... It shows up the same way in the WebScene too.

Re: Coloring of shape edges using CGA

Anonymous User — Tue, 15 Sep 2015 21:34:51 GMT

Might be another copy of the floor faces. You want to post the rule? I'll check it over if so.

Re: Coloring of shape edges using CGA

TessOldemeyer — Tue, 15 Sep 2015 22:01:39 GMT

Absolutely. Thanks!

version "2015.1"

attr Fill_Color = "#FFF80"

attr Outline_Color = "#000000"

attr Transparency = 0.9

@StartRule

AddOutline -->

offset(-0.2) # thickness of your border. Negative value offsets inwards.

comp( f ) {border: color(Outline_Color) MyBorder. | inside: Shape.}

color(Fill_Color)

set(material.opacity, Transparency)

Re: Coloring of shape edges using CGA

Anonymous User — Tue, 15 Sep 2015 22:16:46 GMT

Okay, I just fixed on it for a minute. I simplified it to be more readable. Now you have a start rule, and that rule sends the border to a new rule, and the inside shape to a new rule. Just easier to read/debug that way. Face clashing effect should be gone now. I also reversed the set opacity part, so that increasing that attribute increases the transparency (since opacity is the opposite of transparency):

set(material.opacity, 1-Transparency)

CGA file is attached.

Chris

Re: Coloring of shape edges using CGA

TessOldemeyer — Wed, 16 Sep 2015 14:48:47 GMT

Chris,

It looks a ton better now. Thank you so much for all of your help and time!

Tess