transparency

[Guest daveg4otu]

I've been playing around with texture - both for ground surfaces and buildingg macros- altering and experimenting.What I need to know is what color is default transparent - for instance to make an open doorway so you can see inside a building or to create a "soft edged " ground texture where the underlaying default texture can show thru in places.I thought it would be black - same as in panel bitmaps but so far this hasn't worked.Dave

[Guest luissa]

Hello Dave,In FS5 and FS98 you could get transparency with the black color and some other command issued to the FS graphic engine. Today you can have transparency in a variety of ways. No commands. The transparency is defined solely in the bitmap.For example, in a 32-bit bitmap every pixel has 4 bytes (32 bits). 3 bytes are for red, green and blue and, the 4th represents a transparency level. This 4th plane is called the alpa channel.In 8-bit bitmaps, you have a palette with 256 entries. Following the palette you have the pixel data which is 1 byte per pixel. This byte points to an entry to the referred to palette. Again each palette entry is 4 bytes: red, green, blue and transparency. FS200X interprets this 4th byte as transparency.Enough for explanations. There are a lot of programms that allow you to add transparency to bitmaps. For 8-bit bitmaps, may be you want to try the one I use:http://www.ptsim.com/downloads/transp.zipRegards, Luis

[arno 1]

I would suggest using the alpha channel in the DXT format textures of FS. For DXT1 you have a 1 bit alpha channel, while DXT3 has a 4 bit channel.This means that with DXT1 you can only make on or off transparancies, while DXT3 also allows levels of transparancy.This is a link to a tutorial with some more information about creating them I wrote:http://www.scenerydesign.org/forum/showthread.php?t=57

[Guest daveg4otu]

Thankyou both for the advice.Dave

[Guest bones]

Dave,Get a copy of DXTBmp. Use PSP or whatever to work on your images and then load them into DXTBmp to create the Alpha channel - then save as DXT1 or 3 as appropriate.Imagetool can open DXT formatted bitmaps but it can't manipulate the Alpha channel.boneshttp://fsaviation.nethttp://www.precisionmanuals.com/images/forum/ng_driver.jpg

[arno 1]

I guess it depends on your personal taste, but I never got the alpha channel working properly in DXTBmp. I prefer to edit it directly in my paint program when I design the texture and then just save in a format that ImageTool can read.ImageTool does not have to edit the alpha channel in that case and is only used to convert the texture to DXT.

[Guest daveg4otu]

Success!!- after around 3 hours of "cut and try" ( or if you prefer " suck it and see")I finally made a transparency that actually worked in FS9.This may be crude but I used dxtbmp to open an existing image - created an alpha channel - edited it in Paint and the put it all back together in dxtbmp saving as a dxt3 alpha.I guess better results can be had using PSP ( which my wife has - so should be no problem if I ask nicely)Thanks to all for all the advice.Dave