Using GIMP
Data pubblicazione: 24-mag-2008 22.31.35
Started using GIMP. Found it much more easy and intuitive than photoshop... And it is FREE OF CHARGE!!!
Basic Usage of GIMP for creating alpha-channel: (real semi-transparent images)
1. Open GIMP
2. File->New Image 512x512 pixel
3. Copy there the image you want to ALPHA-CHANNEL
4. Delete standard background layer otherwise you haven't transparence at all
6. Layer->mask->add layer mask specify "Grayscale copy of layer"
7. In layers: apply layer mask to have them applied
8. Export to tga
This effectively generates an alpha channel in a semi intuitive way.
If you only need to have simple ON-OFF transparency than you can act in other ways simply operating on transparent background.