Showing alpha in the 3D viewport?

Hi everyone, i have a little problem.

I’m making an object which has several parts using a non-baked texture. Specifically, they use an image that i’ve created externally (and which has 1-bit alpha in it) and put on the object in blender. i dont intend these parts to ever be rendered, and i just want them to show the image with alpha.

I had this working fine, until the point where i need to link them up. Unfortunately, then i discovered that the alpha seems to vanish in the 3d viewport if i assign any material to those faces. OR in my case, if any material is forcibly assigned when i join them to another mesh. This is causing me headaches.

I know that making the alpha look right in my final output is a different issue altogether, and one that i dont need help with. But i just want it to show properly in the viewport while i’m editing it, as it’s hard to get an idea of how things look with big black squares where my images should be.

2 possibilities i can see :

  • if your system can work with it, try to use GLSL display (in the 3D View press the N key of your keyboard and scroll down until you see the “Display” tab, you will be able to switch between single texture, multitexture and GLSL) , this should display the alpha correctly.

  • if you are using Multitexture display, there’s some strange Blender design that is responsible of the problem you see (once you add a material, the alpha in the viewport suddenly will turn black).
    The command that control material alpha in Multitexture display is actually not in Blender Render mode (that is the primary and default Blender mode), but in Blender Game mode.

To switch :

Then select the material that have your alpha texture and see this panel :

It’s what is controlling the alpha in the viewport, and oddly it is not available in Blender Render mode, but it still control the alpha there too in Multitexture display

The default setting is “opaque” and that’s exactly why in the viewport you see the alpha being black.
Change Opaque into Alpha Blend or Alpha Clip (depending on your need, as you will see the difference in the viewport, with smooth transparency in boundaries or harsh one) and your alpha will be transparent again in the viewport like it was before you added a material.

haii !!

i tried the first one. That was actually a pretty cool effect, it seemed to give dynamic rendering of normal maps, specular and such. i never knew that was there.
unfortunately it also seemed to completely disable the images i had on various faces, which caused a lot of things to turn to solid colours instead. maybe i misunderstood how it’s supposed to work? even toggling the Face Textures and Face Textures Alpha settings, didn’t seem to fix that.

I tried your second solution however, and that worked perfectly. Are there any downsides to having Blender game set? does it cause performance issues or somesuch ? it seems good enough to leave on permanantly, as is

thank you!!

The same as there are some functions missing in the Blender Render mode that are instead available in the Blender Game mode, the opposite is true too, by example you can’t render in Blender Game, the Render panels and its various settings are replaced by game engines display controls instead.

Probably several other similar cases in the various panels, i have not looked too deeply.

The seccond pocture on your post cannot more be displayed.

And if i press the “N”-key in my blender 2.80, it just opens the “Item”, “Tool” and “View”-sidebars of the 3d-viewport, and there is no “Display”-tab.

How do i open, what you open with your “N”-key?