PureBasic Forums - English

Is it possible to place an image into the clipboard and preserve it's alpha channel ? When I use the built in command, the alpha channel is lost.

Thanks !

Do you or anyone else know a similar technique for Linux to access the image data ?

If I'm not mistaken LoadImage returns a pointer to a pb image structure but not to ARGB pixel data. According to the docs the first long of that structure is a Bitmap pointer when using windows or a GdkPixmap pointer when using Linux.

No, I mean to memory. I need an ARGB pixel buffer of a transparent PNG image but I don't have to display the image. If the image is a 256 color palette based image it should be converted automatically. Using the compiler directives to compile for a specific platform I could use GetDiBits_ to solve i...

Is there an easy (preferably linux/windows cross platform) way to load and decode an image into memory ? I looked at the image library but couldn't find such an option. Maybe an alternative could be to use one of the imagePlugin libraries. I noticed viewing the SampleImagePlugin code they have a dec...

Linux version ; purebasic 3.94 linux source UsePNGImageEncoder() Global zf.l Structure zstream next_in.l avail_in.l total_in.l next_out.l avail_out.l total_out.l msg.l state.l zalloc.l zfree.l opaque.l data_type.l adler.l reserved.l EndStructure Procedure.l Z_Compress(dest,destLen,source,sourceLen) ...

After some experimenting I was able to use the PNG plugin to (un)compress a memory buffer using zlib compression. ; purebasic 4.0 windows source UsePNGImageEncoder() Structure zstream next_in.l avail_in.l total_in.l next_out.l avail_out.l total_out.l msg.l state.l zalloc.l zfree.l opaque.l data_type...

How can I compress a memorybuffer using zlib compression on Linux ? I tried LoadLibrary("libz.so") but if I use the purebasic functions to examine the library I get zero library functions. Edit: I found a way to do it using the PNGImagePlugin. The solution is posted in the Tips 'n' Tricks ...

Is it possibly to use the ImagePluginPNG library to compress data in memory ?

I only need the PureZIP_PackMemory functionality from the PureZIP library but since this library doesn't work together with the ImagePluginPNG library and PNG encoding also requires zlib compression I was wondering this.

If you don't mind a little asm, try this Procedure BitSplit(value.q, arrayptr.l) !push ebx !mov eax,dword [esp+8] !mov ebx,dword [esp+12] !mov edx,dword [esp+16] !mov ecx,dword [edx-8] !add edx,ecx !bitsplit_loop: !dec edx !push eax !and al,1 !mov byte [edx],al !pop eax !rcr ebx,1 !rcr eax,1 !loop b...

Actually I am using very large numbers, but I don't think it will matter that much anyways. I guess you are right. For a 56 bit limit value, the difference in chance still should be less then 1%. To detect a significant difference for even bigger values your computer would have to make more then a ...

Are you sure that not all numbers will have the same chance to appear? I don't know how the normal random routine is written; if the chance is equal there. In this case the logic is simple. If a generated number has a maximum value of 16 and you limit the result between 0 and 10 using a modulo inst...

This seems to work but since it uses a modulo not all numbers will have the same chance to appear

Thanks. That really helped :D Do you know if there's also a way to get the DC of the current Window without the need of creating a gadgetlist like El Choni suggested ? I tried if there was a similar way like _PB_Window_GlobalStructure but that didn't work. By the way, where did you find that informa...

Unfortunately that doesn't solve my problem. My lib has some custom drawing functions. In order for them to work the same way as the normal PB drawing functions I need a way for the lib to find the currentDC so it doesn't have to be specified each time a function is used. Using PB 3.9x it wasn't a p...