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Curve image 90 degrees - Printable Version

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Curve image 90 degrees - RealGomer - 04-19-2019

I'm trying to take an image of straight roadway and place a 90 curve in it. I figured out how to get any other curve but 90 deg doesn't look right. Any suggestions? The image will be part of a diorama layout.


RE: Curve image 90 degrees - rich2005 - 04-20-2019

(04-19-2019, 10:45 PM)RealGomer Wrote: I'm trying to take an image of straight roadway and place a 90 curve in it. I figured out how to get any other curve but 90 deg doesn't look right. Any suggestions? The image will be part of a diorama layout.

All depends on the image of the straight roadway. Is it plain colours, or does it have a texture?

I would be inclined to create one using paths and selections but another way is using the Filters -> Distorts -> Polar Co-ordinates filter.

This a very quick (not much of a) demo: 4 and a bit minutes.

https://youtu.be/G9dAbxWqlnM

Have a look, if you think it might work for you, come back with questions.


RE: Curve image 90 degrees - Ritergeek - 04-20-2019

If I needed to do this, I could follow the video, but do not like the results for this purpose. Everything but the shape is distorted to the point it does not look real. I might use this method to create the basic shape, then fill it all at one go on an asphalt layer to avoid distorting texture, then I'd do a curved path for the center line and stroke that with dashes. My challenge is finding a way to get a dashed line to bend around a curve. Actually, that's getting any brush shape to rotate as it follows a curve. If that road is very long, defining a path with individually bent stripes would be untenable.

I am able to create a small rectangle object to use as a stripe component. When I copy that, select the clipboard image as a brush, and set spacing to 2.5 times the long dimension of the shape, I can use a rectangular selection to fill portions of the path. My shape was horizontal when I created it, so that works for the horizontal portion of the stripe. With a new selection, I rotate the brush 90° to fill the vertical part of the path. But the curve? That stymies me.


RE: Curve image 90 degrees - Ofnuts - 04-20-2019

(04-20-2019, 02:51 PM)Ritergeek Wrote: My challenge is finding a way to get a dashed line to bend around a curve. Actually, that's getting any brush shape to rotate as it follows a curve. If that road is very long, defining a path with individually bent stripes would be untenable.

For the dashed line:
  • create a path
  • Edit>Stroke path
  • In the Line style options you can pick one of the standard dash patterns or create your own.
For a brush shapes that rotates to follow a curve, there is the "Track direction" brush dynamics, or any dynamics you define yourself that binds Angle to Direction. Hint: start with an upside-down brush.


RE: Curve image 90 degrees - Ritergeek - 04-20-2019

(04-20-2019, 03:00 PM)Ofnuts Wrote: For the dashed line:
  • create a path
  • Edit>Stroke path
  • In the Line style options you can pick one of the standard dash patterns or create your own.
For a brush shapes that rotates to follow a curve, there is the "Track direction" brush dynamics, or any dynamics you define yourself that binds Angle to Direction. Hint: start with an upside-down brush.

Well now, that is awesome to know. Both techniques are so simple! The Track Direction dynamic worked like a charm. I made a simple gingerbread person for a brush and made it hold hands around a circle. Yes! Varying the angle of the brush got interesting results too.


RE: Curve image 90 degrees - skinbus - 04-25-2019

(04-19-2019, 10:45 PM)RealGomer Wrote: I'm trying to take an image of straight roadway and place a 90 curve in it. I figured out how to get any other curve but 90 deg doesn't look right. Any suggestions? The image will be part of a diorama layout.

Can I assume you've tried 
curve bend?


RE: Curve image 90 degrees - Ofnuts - 04-25-2019

(04-25-2019, 05:06 PM)skinbus Wrote:
(04-19-2019, 10:45 PM)RealGomer Wrote: I'm trying to take an image of straight roadway and place a 90 curve in it. I figured out how to get any other curve but 90 deg doesn't look right. Any suggestions? The image will be part of a diorama layout.

Can I assume you've tried 
curve bend?

Curve bend is  a vertical displacement along a curve, not a curve around a point.


RE: Curve image 90 degrees - RealGomer - 09-14-2019

Skinbus: Yes I found and use Filter> Distort> Curve Bend. Unfortunately if I want to make successively sharper bends it become hit or miss to go from a 5 deg curve to a 10 deg curve.

Ofnuts: I'm not sure what you mean by "Curve bend is  a vertical displacement along a curve, not a curve around a point." Isn't vert disp what I want to creat curve in road images? I'm making a series of print and then put them together to get the roadway I need.


RE: Curve image 90 degrees - Ofnuts - 09-15-2019

(09-14-2019, 10:51 PM)RealGomer Wrote: Ofnuts: I'm not sure what you mean by "Curve bend is  a vertical displacement along a curve, not a curve around a point." Isn't vert disp what I want to creat curve in road images? I'm making a series of print and then put them together to get the roadway I need.

No, in  a road image you want things to follow the local direction of the curve (in other words, to be oriented following the local tangent to the curve). If you were painting with the brush you would use the "Track direction" dynamics.

In other words, you want this

[attachment=3157]

While curve bend would give this:

[attachment=3156]