UV layout face orientation adversely effects how the texture appears when rendered. #42063

New Issue

Jerry Dechant · 2014-10-03T19:55:09+02:00

Jerry Dechant commented

2014-10-03 19:55:09 +02:00

System Information
Operating system and graphics card: Windows 7, 64 bit, Nvidia GForce GTX 580

Blender Version
Broken: (example: 2.69.7 4b206af, see splash screen) : 2.71 Date: 2014-06-25 18:36, Hash 9337574
Worked: (optional)

Short description of error
The textures from UV Map faces which have been rotated 180 degrees on the UV Map, do not render properly.

Exact steps for others to reproduce the error
Based on a (as simple as possible) attached .blend file with minimum amount of steps

After having marked seams, I use UV Mapping, Unwrap, Unwrap. I split the window so I have the edit window open and the UV/Image Editor windows open. I re-position the faces to make the best use of the map area, and in some instances, I stack similar faces on top of each other. In order to do this, I may have to rotate a face 180 degrees in order to stack the faces. I then export the UV layout to an image editor and apply textures appropriately, I apply the texture by choosing "Image or Movie" find the appropriate file on my hard drive and then load it. Under Mapping, I choose UV for coordinates. I leave projection as flat and no adjustments to any other settings. I leave the Influence check mark in the Diffuse color box and the value at 1.000. Then I use Blender Render and position the item appropriately in the camera view using 3 point lighting system. Press F12 to obtain the image. I noticed that some of the textures which were stacked on the diffuse UV Map don't appear as sharp, they seem faded in intensity. So I did some experimentation to determine what the problem was. I found out if I rotate a UV unwrapped face on in the UV/Image Editor 180 degrees it adversely effects how the texture is rendered for those faces. This indicates to me there is some face orientation information for those faces which shouldn't be present in the UV Map layout data. If I mirror the face either X then Y or visa versa, the adverse effect doesn't show up.

I've attached an example image where I show a plane divided into 4 triangles. The top row shows the UV Map layout unaltered. The second row shows the bottom triangle rotated 180 degrees and placed over the top triangle. You can see on the image to the right on the second row, the adverse effect of rotating the UV face.

If you need more information, please let me know.

**System Information** Operating system and graphics card: Windows 7, 64 bit, Nvidia GForce GTX 580 **Blender Version** Broken: (example: 2.69.7 4b206af, see splash screen) : 2.71 Date: 2014-06-25 18:36, Hash 9337574 Worked: (optional) **Short description of error** The textures from UV Map faces which have been rotated 180 degrees on the UV Map, do not render properly. **Exact steps for others to reproduce the error** Based on a (as simple as possible) attached .blend file with minimum amount of steps After having marked seams, I use UV Mapping, Unwrap, Unwrap. I split the window so I have the edit window open and the UV/Image Editor windows open. I re-position the faces to make the best use of the map area, and in some instances, I stack similar faces on top of each other. In order to do this, I may have to rotate a face 180 degrees in order to stack the faces. I then export the UV layout to an image editor and apply textures appropriately, I apply the texture by choosing "Image or Movie" find the appropriate file on my hard drive and then load it. Under Mapping, I choose UV for coordinates. I leave projection as flat and no adjustments to any other settings. I leave the Influence check mark in the Diffuse color box and the value at 1.000. Then I use Blender Render and position the item appropriately in the camera view using 3 point lighting system. Press F12 to obtain the image. I noticed that some of the textures which were stacked on the diffuse UV Map don't appear as sharp, they seem faded in intensity. So I did some experimentation to determine what the problem was. I found out if I rotate a UV unwrapped face on in the UV/Image Editor 180 degrees it adversely effects how the texture is rendered for those faces. This indicates to me there is some face orientation information for those faces which shouldn't be present in the UV Map layout data. If I mirror the face either X then Y or visa versa, the adverse effect doesn't show up. I've attached an example image where I show a plane divided into 4 triangles. The top row shows the UV Map layout unaltered. The second row shows the bottom triangle rotated 180 degrees and placed over the top triangle. You can see on the image to the right on the second row, the adverse effect of rotating the UV face.![blender_bug.jpg](https://archive.blender.org/developer/F114460/blender_bug.jpg) If you need more information, please let me know.

Jerry Dechant commented

2014-10-03 19:55:09 +02:00

Changed status to: 'Open'

Jerry Dechant commented

2014-10-03 19:55:09 +02:00

Added subscriber: @JeromeDechant

Bastien Montagne commented

2014-10-04 14:33:43 +02:00

Added subscriber: @mont29

Bastien Montagne commented

2014-10-04 14:33:43 +02:00

Not sure I understand the issue… Please always attach a .blend file to illustrate your reports (and embed needed picture in ti, too).

Bastien Montagne commented

2014-10-11 15:14:06 +02:00

Changed status from 'Open' to: 'Archived'

Bastien Montagne closed this issue

2014-10-11 15:14:06 +02:00

Bastien Montagne self-assigned this 2014-10-11 15:14:06 +02:00

Bastien Montagne commented

2014-10-11 15:14:06 +02:00

No news since one week…

Jerry Dechant commented

2014-10-11 18:36:16 +02:00

The example I expressed above is a simple one where only a flat plain is created and then "j" is used to dissect the plane into triangles. I don't think including a blend file will help resolve this issue or provide any additional information, that is why I didn't include one. If you open Blender, delete the default cube and create a flat plane, then dissect it into triangles, then unwrap that. you can apply a diffuse map or normals map to the UV map layout which is what I did in the pictures to the right. You can stack the triangles one on top of the other, rotating either the top or bottom triangle (rather than mirror flipping it,) and then when you apply the map to the geometry, you will see the effect my pictures represent.

If you still want a blend file, I can make one for you, but like I said, the example is simple enough to create your own.

The example I expressed above is a simple one where only a flat plain is created and then "j" is used to dissect the plane into triangles. I don't think including a blend file will help resolve this issue or provide any additional information, that is why I didn't include one. If you open Blender, delete the default cube and create a flat plane, then dissect it into triangles, then unwrap that. you can apply a diffuse map or normals map to the UV map layout which is what I did in the pictures to the right. You can stack the triangles one on top of the other, rotating either the top or bottom triangle (rather than mirror flipping it,) and then when you apply the map to the geometry, you will see the effect my pictures represent. If you still want a blend file, I can make one for you, but like I said, the example is simple enough to create your own.

Jerry Dechant commented

2014-10-11 20:21:29 +02:00

UPDATE: I just downloaded the latest version of Blender and tried to duplicate the problem. It appears to have been resolved. As far as I can tell, each face appears properly. You may close this bug report. Thank you for your assistance and attention to this matter.

Best regards,
Jerry

UPDATE: I just downloaded the latest version of Blender and tried to duplicate the problem. It appears to have been resolved. As far as I can tell, each face appears properly. You may close this bug report. Thank you for your assistance and attention to this matter. Best regards, Jerry

Sign in to join this conversation.

No Label

Download

What's New

Blender Studio

Manual

Developers Blog

Documentation

Benchmark

Blender Conference

Development Fund

One-time Donations

UV layout face orientation adversely effects how the texture appears when rendered. #42063