wxImage & DIB suggestions Topic is solved

[spectrum]

hi all,
i was wandering if my approach of displaying a DIB is correct.

I have a DIB in memory, generated from a commerical graphic library.

Using wxWidget 2.8 im using the following procedure to display it, and mantain the application win/mac portable.

1) i mirror the Y axis (my own function) of the bitmap in memory (DIB are stored with lines reversed).
2) sometime the DIB is 8bpp, so when necessary, i convert 8bpp to 24bpp (my own function).
3) i give the 24bpp buffer to the wxImage constructor.
4) i create a wxBitmap(wxImage)
5) i use dc.DrawBitmap

This procedure works fine, but i'm not sure if i can avoid some steps, if i'm missing something to make it easier.


Many thanks, Angelo

[Trikko]

hi all,
i was wandering if my approach of displaying a DIB is correct.

I have a DIB in memory, generated from a commerical graphic library.

Using wxWidget 2.8 im using the following procedure to display it, and mantain the application win/mac portable.

1) i mirror the Y axis (my own function) of the bitmap in memory (DIB are stored with lines reversed).
2) sometime the DIB is 8bpp, so when necessary, i convert 8bpp to 24bpp (my own function).
3) i give the 24bpp buffer to the wxImage constructor.
4) i create a wxBitmap(wxImage)
5) i use dc.DrawBitmap

This procedure works fine, but i'm not sure if i can avoid some steps, if i'm missing something to make it easier.


Many thanks, Angelo

Do you call these steps many times?
Are dib dimensions fixed?

[spectrum]

the application display a particular XY graph. For now i've fixed it to 640x480, and i recall the procedure everytime i zoom or i move the diagram.

[Trikko]

the application display a particular XY graph. For now i've fixed it to 640x480, and i recall the procedure everytime i zoom or i move the diagram.

Maybe you can speedup a bit using a single wxImage everytime, and updating its buffer copying memory from dib to wxImage buffer (using memory functions like memcpy).

I know there're some undocumented classes that you can use to access to raw bitmap data maybe. In this case you can use wxBitmap only (without wxImage)

[upCASE]

I know there're some undocumented classes that you can use to access to raw bitmap data maybe. In this case you can use wxBitmap only (without wxImage)

There's a file called rawbmp.h that contains just that. It contains some example code as well. Can be pretty handy.

[spectrum]

many thanks