UVMapping alphamapped textures in the viewport

Hello all and Merry Christmas. This is my very first post here and I’m awfully sorry it’s in the form of a question. But I’ve been hanging around for quite a while, and I know what nice helpful chaps you are.

I’ve been using blender for yonks to entertain myself in CG. Not nearly as good as you lot but it keeps me quiet. A year ago or so I started modelling addon scenery for MS Flightsim 2004 using GMax, and learned just how clunky Max’s interface is compared to blender’s.
I recently discovered the ability to export directX files from blender and using FS2004’s compiler to make scenery directly, rather than modelling in blender and exporting to DXF and importing my model insto GMax. Which is what I’ve done up till now.

I’d very much like to use blender for this whole process, but I’ve come across one major difference that has me stumped…

Could a kind hearted fellow please let me know if it’s possible to set blender up to display UVmapped textures with alpha map in the viewport in a way I was accustomed to in GMax.

Let me explain…

This is an image of my nearly completed Palm house of Kew Gardens in GMax, note the way textures are displayed with alpha maps. I had to create a seperate opacity map to achieve this in GMax. But this is what I would like to see when working with blender.


When working with blender, I select the “Texture” shading to achieve the following view… but it will not make use of the alpha map?
This is a view of very early work in progress of the Princess of Wales conservatory, I’ve applied the UVmapping and it’s still under the “Texture” shading method.


I thought that perhaps I needed to go back to the “Shaded” view, to see if it would display the material with a seperate opacity map. But discovered the texture is displayed without the UVmapping. (After I selected “Shadeless” in the material dialogue. Took me while to figure out why it was showing only in black)
I also noticed that the texture is displayed at an enormously low resolution in “Shaded” view compared to “Texture”


And just to clarify, here is exactly the view I am after. Only it’s in GMax, not blender :frowning:


I really hope I can achieve this in blender. If anyone knows how, would you be a pal and let me know how too. I find it so much easier to model if I can see through the alpha map nd to be honest I’d much rather dump GMax and carry on with blender alone.
Even if this is not possible, I just want to say thanks to everyone for the wisdom I have already gleaned from these forums in the past. You’re such helpful chaps. :slight_smile:

Many thanks


ps, if anyone’s interested in my Kew Gardens scenery for FS. Here are some screenshots from Flight simulator 2004 :slight_smile:


Blender works a little differently. The UVMapping functions were originally added for use by the GameEngine which doesn’t use Materials. In the Render Engine only Materials and the textures linked to them can display Alpha transparency.

The workflow is map your texture to the object(s) in the UVEditor. Add a material, then add that same Image as a Texture in F6. Set the Alpha option for the texture there (UseAlpha if it’s a .png or .tga that has a dedicated alpha layer or CalcAlpha if you want black [or white] to be calculated as alpha). Back in Materials (F5) in the Material tab set the Alpha value of the material and in the RayMirror tab set it to ZTransp or RayTrans if it raytraced. In the MapInput tab you want to change the texture mapping from ORCO (original Co-ords) to the UV co-ords of the UVMapped texture. In the MapTo tab map the texture to Alpha.


Thanks very much for replying Fligh %.

That’s pretty much what I had done so far except for setting Z/Ray transparency. As I had little intention to render the scene, only to export the mesh, I didn’t adjust either of these values.
Upon trying, I discovered that these values don’t affect the transparency in the viewport :frowning:

Were your instructions related to viewport or just upon rendering? As I am still not getting transparency while I work.
I’m sure I’ve seen blender display stuff in the viewport this way. I could be wrong though.

Again thanks for your help :slight_smile:


In the F7 Object Draw type, there is a button under Draw Extra labelled Transp. Turning this on makes the object semi-transparent in the 3d window if you have the alpha value set to something less than 1. Turning it down all the way to zero makes it invisible in the 3d window… doesn’t work with UV mapped transparencies, though, it seems… it affects the entire object, not transparent mapped UV alpha textures. Maybe something to develop for future versions, perhaps?

Were your instructions related to viewport or just upon rendering?

My bad. You’ll only ever see the UVmapped texture in the Viewport and thus no transparency. Shaded mode (Shft-Z) shows the Material texture but it draws it as Vertex colors, ie: the more you subdivide the more you can see but it never gets close to pixel depth.

Also, if you have UV tex plus Material tex then the UV masks the transparency of the material tex with F7 option on.

Transparency is therefor only possible in the Render if UV’s are used.


Thanks very much for your replies and advice. It’s a shame (to me) that blender can’t display textures the same way GMax does. I can cope with that though.

Grafix, that advice you gave sure is interesting. That could very well be the reason why I thought I had seen transparencies in the viewport, in the past.

I suppose I’ll have to carry on with my current work method. Modelling in blender and then texturing in GMax. What a shame, I was hoping to leave GMax out of the loop.
Would it be presumptuous of me to put in a feature request with the blender development chaps, I wonder?

Again, many thanks for sharing your wisdom.