[SOLVED] How to load textures on an OBJ model?

[oetzi]

Hello,

I am new to this topic and have problems with loading textures correctly onto my 3D object.
What I successfully did so far was to load a 3DS model and to put the textures on it via the TextureManager.

But now I have to use a OBJ model. The background is that I did a 3D scan of my face and got the following files:
- oetzi.obj
- oetzi_MATERIAL.mat
- oetzi_TEXTURE-0.jpg
- oetzi_TEXTURE-1.jpg
- oetzi_TEXTURE-2.jpg

The MATERIAL files contains this:

newmtl material_0
map_Kd oetzi_TEXTURE-0.jpg
newmtl material_1
map_Kd oetzi_TEXTURE-1.jpg
newmtl material_2
map_Kd oetzi_TEXTURE-2.jpg

So I changed the Loader.load3DS(...) method to Loader.loadOBJ(InputStream objStream, InputStream mtlStream, float scale).
My first attemp was to set the 2nd paramter to null and to keep the approach to load the texture first into the TextureManager and then use "obj3D.setTexture("material_0")". The result was that my 3D model was displayed but the textures were a total mess.

Then I thought that there might be a reason, why loadOBJ has this second inputStream called mtl :-)
So I tried to load this .mat file as second inputStream

Code Select Expand


inputStreamMTL = masterContext.getAssets().open("3d-objects/oetzi-obj/oetzi_MATERIAL.mat");
and used it as second paramter for the loadOBJ() method.

Unfortunately, I do not know what I have to do now in order to get the textures onto the 3D model. All I tried so far, did not work.

Therefore, I would be grateful to get a brief explanation, how I have to handle the .obj, the .mat and the texture files to get my final 3D model displayed.

Greetings,
oetzi

[EgonOlsen]

The easiest way is to load them before the model and add them to the TextureManager using the names that they have in the .mtl-file (for example: oetzi_TEXTURE-2.jpg). Then, the OBJ-loader will assign them automatically. Here's a brief description of this behaviour: http://www.jpct.net/wiki/index.php/Loading_models

[oetzi]

Thanks EgonOlsen for your fast response, it works!
The solution can be so easy if you know how to do it :-)

Grüße aus Köln :-)

[drdla]

Hi, I have same problem.
And If I use this code, my application falls because Caused by: java.lang.OutOfMemoryError: Failed to allocate a 603979788 byte allocation with 15867456 free bytes and 169MB until OOM.

If I don´t use this code my object is loaded correctlly but without texture.

Code Select Expand


        Texture texture = new Texture(BitmapHelper.rescale(BitmapHelper.convert(mContext.getResources().getDrawable(R.drawable.mash_u1_v1)), 64, 64));
        TextureManager.getInstance().addTexture("texture", texture);
        object3D.calcTextureWrap();
        object3D.setTexture("texture");
        object3D.strip();
        object3D.build();


[EgonOlsen]

What do you expect? You seem to be loading a texture larger than 500mb... ...I've no idea what this is supposed to be, but whatever it is: It's waaaaay too large. Ironically, you actually want to scale it down to 64*64 with that line of code. If that's your goal, just rescale your texture to 64*64 in some image editor and load that one...without all these rescale and convert calls. It's never a good idea to let the device do the scaling when you can do it in pre-processing.

[drdla]

But my texture have 948 KB.

And if I change to this code:

Code Select Expand

texture = new Texture(getInputStream("starwarsmodel/mash_u1_v1.jpg"));

private InputStream getInputStream(String fileName) {
        InputStream stream = null;
        try {
            stream = mContext.getAssets().open(fileName);
        } catch (IOException e) {
            e.printStackTrace();
        }
        return stream;
    }



My app falls because of same oxception: OutOfMemoryError: Failed to allocate a 67108876 byte allocation with 16777216 free bytes and 39MB until OOM

On line:

Code Select Expand

world.draw(fb);

[EgonOlsen]

But my texture have 948 KB.

No, it doesn't. You are confusing the compressed file size with the size in memory. Your texture is too large for your device (or for any device). It's as simple as that. Just load your texture in some image editor and you'll see it's actual size. Multiply width and height, multiple again by 4 and double the result. That's roughly the amount of memory that you need at least to load and process that thing. Just scale it down!

BTW: If you absolutely have to use this texture in its original form, you can add the largeHeap flag to your manifest. That will increase the VM's memory on most devices: https://developer.android.com/guide/topics/manifest/application-element.html.