Lzo compression?

[jimk72]

I have been looking all over for any info on using this with delphi. I am translating a c++ app to delphi and they use lzo compression to load and save textures and I can't seem to find a delphi version anywhere? I have found minilzo.obj but has NO information or examples on how to use it, and every time I try it errors.

Thanks in advanced for any help!

 

[BobbaFet]

i think componentace.com has that compression type

BobbaFet

if not Programming = 'Severe Migraine' then
                       ShowMessage('Eureka!');

 

[jimk72]

Thanks for the reply! I checked and they have alot of compression types but not Lzo type. Thanks anyway for your time.

 

[melmitts]

You might find some useful information here...

http://www.oberhumer.com/opensource/lzo/

 

[jimk72]

Yea thats the only thing I found that was helpfull, It seems he hasn't built a delphi version yet. Oh well I will just give up. I spent to much time already translating the original app to delphi, I cant translate another library just to get the app to work.

Thanks so much for your replys!

jimk

 

[earthandfire]

Why are you trying to translate the library to Delphi? Surely you can use the .dll directly (or if its not precompiled, download a free c/c++ compiler to do it for you - it shouldn't matter what language the library is written in.

I used to do a lot of work in various versions of Access. Whenever I needed to produce an external library I always used Delphi to write the .dll and never had any problems accessing it through Access.

Hope this helps.

 

[jimk72]

I tried but it kept giving me an access violation error.
In c++ you would do
BYTE *texture = new BYTE[datasize+headersize];
BYTE *unpackedtexture = new BYTE[unpackeddatasize+unpackedheadersize];
texture is then loaded from the file and sent to be uncompressed.

lzo1x_decompress(texture, fileHeader.PackedSize, unpackedtexture, fileHeader.unPackedSize, NULL);

texture is a pointer to where the byte array is allocated in the c++ source.
My translation was:
var
texture:array of byte;
unpackedtexture:array of byte;
begin
setlength(texture, datasize+headersize);
setlength(unpackedtexture, unpackeddatasize+unpackedheadersize);
I fill texture with the file to be uncompressed and send it to lzo the same way c++ source does.

lzo1x_decompress(@texture, fileHeader.PackedSize, @unpackedtexture, fileHeader.unPackedSize, NULL);

and Thats when I get the access violation?
as you can see you are supposed to send a pointer to the spot in memory where the texture is so I used @ to get the address.Since this did not work I tried using a pointer to point to texture and sending the pointer and the same result happens.

 

[earthandfire]

It could have something to do with your Delphi declaration of the dll.


Hope this helps.