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darksalad
02-01-2009, 03:35 PM
okay this may sound like a stupid question, but how do transparencies(white areas not existing and being clear around the entity/tile you want to place on map) work in novashell.
Every time I add something to say the example tiles in the dragoneggs tutorial the white areas appear again.

Seth
02-06-2009, 03:07 AM
Ok, two ways of doing transparency:

1. Color key. Use Utilities->Import image, then when you see a list of images, you can double click the filename to set specific properties, such as the color key. (see attached pic)

Note, the numbers 255,255,255,255 mean white is the transparent color. ( R G B A.. hmm, wonder why I'm asking for the A (alpha), shouldn't care about that..)

2. Use a .png or .tga that has its own alpha channel, this also looks better as you can use a smooth gradient of translucency instead of just the basic transparency.

donfelipe
06-09-2009, 03:12 AM
Ok, two ways of doing transparency:


Note, the numbers 255,255,255,255 mean white is the transparent color. ( R G B A.. hmm, wonder why I'm asking for the A (alpha), shouldn't care about that..)


Maybe the sample had a 32-bit image, so there was an alpha channel, but hey just because it's got alpha in it doesn't mean it's gotta be used for transparency. Sometimes it denotes a selection mask, sometimes other things, it's up to the application.... and perhaps someone just saved a 24-bit image as a 32-bit image and so in went the alpha, with no real info but still it's in there.

You can indeed key on a color even if alpha is present. It's a matter of ignoring the alpha. Dogwaffle does similar things in the brush color-keying. It starts with alpha if it detects one but you can override.




2. Use a .png or .tga that has its own alpha channel, this also looks better as you can use a smooth gradient of translucency instead of just the basic transparency.

Whichever imaging tool you use (Photoshop, Artweaver, GIMP, Dogwaffle, ...) may even offer other formats with 32-bit support, like Tiff, Bmp, etc... but whichever you use, make sure it's 32-bit deep in all. There are some extended formats of BMP for example which hold an alpha cannel but the depth is just 16 bit and the alpha for transparency is just 1, 2 or 4 bits deep. These are specially crafted formats used in some DirectX games, including FlightSimulator, TrainSim and such. Conversion tools beetween these extended BMP formats can be found for free at fly.to/mwgfx or also thebest3d.com/dogwaffle/3rdpartyplugins (look for the flightsim plugins and subsequent links)

Targa is quite a good format for this (used in Dogwaffle as the default format). PNG is a little more common in imaging tools, Targa more in animation tools. Png is commonly displayed by most web browsers too. Even Windows knows how to display a PNG gthumbnail. You can teach Windows to display thumbnails for Targa files too, for example with the ThumbPlug TGA plugin (also listed in the 3rdparty plugins section mentioned above).

Hope this helps.