Transparency in the 3D View

Vince_Bly · April 28, 2018, 2:49am

Some time ago I was creating some vines for a mod. The leaves were 6 quads mapped with a photo of a leaf. The area beyond the periphery of the leaf was transparent.

Everything worked as expected. I highlighted ZTransp, set A in the material panel to 0.00, and ticked Alpha in the Map To panel. The export (to a .nif file) correctly showed the leaves with the portions of the meshes beyond the edges of the leaves as transparent. Of course, Blender’s 3D view, with Draw type set to Textured, didn’t show the transparency (see attached image 1).

However, one day I did something and, all of a sudden, Blender’s regular 3D view showed the leaves with transparency (see attached image 2). I have methodically gone through every Blender parameter and cannot find a difference between the textured view showing the transparency or not. Note, I am talking about the 3D modeling view, not a rendered image.

If anyone can shed some light on this, it would be much appreciated.

Attachments

Richard_Marklew · April 28, 2018, 2:49am

Have you Transp selected for your object ?

Vince_Bly · April 24, 2018, 8:29pm

Richard,

Yes, I have tried that. It doesn’t seam to have any effect in the 3D view with Draw type set to Textured. With Draw type set to Solid, ticking the Transp box makes the objects disappear.

Vince

AlejandroSoto · April 24, 2018, 8:29pm

http://vimeo.com/2456205

Vince_Bly · April 24, 2018, 8:36pm

AlejandroSoto,

'Sorry for the delay in responding. Something about RL. Thanks for your suggestion. I looked at the video. What’s done in the video is much more complicated that what I have. At least I can take the mesh I have, duplicate it, and use it as a kind of transparent primitive.

jrboddie1 · April 24, 2018, 8:36pm

Could the difference be using Multitexture vs GLSL materials?

andreola · April 28, 2018, 2:56am

i agree with jrboddie1 that you need to change to glsl materials

Attachments

Vince_Bly · April 24, 2018, 8:45pm

jrboddie1 & andreola,

Thanks for the suggestion. I found that if I switched to GLSL materials, I could see the transparent objects as transparent in the 3D window with Draw type set to Textured. However, the opaque portions looked black until I unticked Enable Lights in the GLSL Material Settings.

This is handy as anyone can do it with any mesh mapped with a transparent texture (with Ztransp highlighted on the Links and Pipeline panel, A set to 0.00 in the Materials panel, and Alpha highlighted in the Map To panel). Unfortunately, it only works in Object mode.

The transparency I got by accident works with Multitexture materials in both Object and Edit modes as shown below. I wish I knew how I did it. For complex objects with many transparent meshes, like the vines shown, being able to edit while seeing the transparency is very handy.

jrboddie1 · April 24, 2018, 8:45pm

Post a .blend please. Don’t forget to pack the texture.

Vince_Bly · April 28, 2018, 3:03am

jrboddie1, I’ve attached a blend file with a transparent-in-the-3D-view mesh. I’ve also attached the transparent texture. I really hope you can figure out how to reproduce this from scratch.

Attachments

Transp01.blend (142 KB)

jrboddie1 · April 24, 2018, 8:46pm

I don’t know what is going on. But it is very cool!

Your file did work for me. Unfortunately, I am using 2.53 which, I think, is missing some features that may be relevant to this phenomenon. (My installation of 2.53 from the Blender Foundation overwrote 2.49.)

In particular, this may be a Texture Face Material. In Edit Mode, check out the Mesh Panel (F9) and ‘Mesh Text Face: Use Alpha’ button. (You may also have to select Texture Face Material in the Games Menu.)

Sorry, I can’t try it myself because this is not yet implemented in 2.53.

Vince_Bly · April 24, 2018, 8:46pm

jrboddie1, thanks. What you suggest works, with one minor limitation.

Based on my experience with the transparent vine leaves and your suggestions, this is what I think happened and how others can reproduce the effect.

I believe the vine leaves were initially set to this state during an import of a .nif file. As I discovered this transparent effect sometime after importing several versions of the leaves, I cannot identify which .nif file or what parameters led to this.

However, based on jrboddie1’s suggestion, anyone can reproduce the result (with Blender versions 2.48a through 2.49b) as follows:
1> Add a plane mesh.
2> UV map a partially transparent texture to it. (click the hourglass icon in the UV map window to see the alpha image).
3> Press F9 and locate the Texture Face panel. It shares a tab with Multires and only appears when in Edit Mode.
4> In Edit mode, set selection mode to face and select the face of the plane.
5> In the Texture Face panel under Active Face Alpha Blending (Transp), highlight Alpha.

That’s it. The plane will now display as transparent with Draw type set to Textured (in both Object and Edit mode). It will also display with transparency with Draw type set to Solid if Solid Tex is highlighted in View Properties.

There is a limitation. If you try this on a mesh composed of many faces, only the active (last face selected) will be converted. However, you can convert all the faces by following the steps listed above with all faces selected. Although only the last face selected will be converted, if you now click the Copy button just to the right, the alpha property of that face will be copied to all the other selected faces.