QDiffuseSpecularMaterial diffuse texture

JanWillemsen

Hi,

I would like to use a texture for the diffuse component of a QDiffuseSpecularMaterial. In the documentation I find for the diffuse property:

"Holds the diffuse color of the material that is emitted for rough surface reflections with the lights. This can be either a plain color value or a texture."

but how do I give it a texture (loaded from a png on disk)? It expects a QVariant...

Jan

kippa

Just found this issue here. I am also having the same problem. QVariant is not happy with QTexture2D.

I am Using 5.12.3 at the moment, but maybe I'd better check 5.13.
Kipp

kippa

@kippa Same on 5.13.0. I must be missing something.

JanWillemsen

@kippa After a lot of trying, I succeeded by doing the following

Qt3DExtras::QDiffuseSpecularMaterial* material = new Qt3DExtras::QDiffuseSpecularMaterial(_renderData);
Qt3DRender::QTexture2D* tex = new Qt3DRender::QTexture2D(_renderData);
SVGTexture* texIm = new SVGTexture(texture, static_cast<int>(width), static_cast<int>(height), tex); //Subclass of QPaintedTextureImage with SvgRenderer to use an svg as texture
tex->addTextureImage(texIm);
texIm->update();
material->setDiffuse(QVariant::fromValue(qobject_cast<QObject*>(tex)));

Hope this helps.

Jan

kippa

JanWillemsen Thanks. Of course it's the cast. Works like a charm. Thanks for getting me out of my mental quicksand. Perhaps QVariant will become qabstracttexture aware someday.

kippa

I eventually found this to work for me

texture = new Qt3DRender::QTexture2D();
material = new Qt3DExtras::QDiffuseSpecularMaterial();
material->setAlphaBlendingEnabled(true);
material->setAmbient(QColor(0xff,0xff,0xff,0x00));
// SymbolImage is my subclass of qabstracttexture
img = new SymbolImage(name, material, blah, blah, blah,  blah,  blah);
texture->addTextureImage(img);
// the two textures are identical for my work
material->setDiffuse(QVariant::fromValue(texture));
material->setSpecular(QVariant::fromValue(texture));

So just QVariant::fromValue().

Then later upon a callback:

/// assume diffuse is same as specular, or use specular
QTexture2D *t = material->diffuse().value<QTexture2D*>();
SymbolImage *s = static_cast<SymbolImage*>(t->textureImages().first());

That's what I ended up using.