Has anyone ever gotten Surface.GetPalette to work?

[Sastraxi]

I've tried EVERYTHING, and nothing works. This is the code that's loading a 256-colour bitmap, in a 256-colour 640x480 fullscreen window:

'Set Logo surfaces.
    dLogo.lFlags = DDSD_HEIGHT Or DDSD_WIDTH Or DDSD_CAPS
    dLogo.ddsCaps.lCaps = DDSCAPS_OFFSCREENPLAIN
    dLogo.ddpfPixelFormat.lFlags = DDPF_PALETTEINDEXED8
    dLogo.lWidth = 640
    dLogo.lHeight = 480
    
    Set Logo = DD7.CreateSurfaceFromFile(App.Path & _
    "\resource\logo.bmp", dLogo)
    
    'Get Palette
    Set SavePalette = Logo.GetPalette
    SavePalette.GetEntries 0, 256, SavePalEntries()

And it always gives me "Automation Error | Unspecified Error" highlighting the GetPalette method.

Help...?

[Sastraxi]

Okay, an update.
I added "Or DDSD_PIXELFORMAT" to the .lFlags parameter and now it's bombing out on the CreateSurfaceFromFile method, with "Automation Error".

[CornedBee]

I guess there is no need in VB to zero out unused fields or set the size of structures, right?

[Sastraxi]

Really... Please explain, I have the feeling you will be able to solve my problem

[CornedBee]

In C++, when I use any struct like DDSURFACEDESC2, I first have to do two things:

DDSURFACEDESC2 ddsd;
ZeroMemory(&ddsd, sizeof(DDSURFACEDESC2));
ddsd.dwSize = sizeof(DDSURFACEDESC2);

The first line is like
Dim ddsd as DDSURFACEDESC2

The second fills the complete struct with 0.
The third sets the dwSize member (that's lSize in VB) to the length of the struct ( Len(DDSURFACEDESC2) ).

Then I can set the members I need. If I don't do that, nothing will work.

Now I suspect, since all DX calls are wrapped in VB, that you don't have to do that. Am I right?

[Sastraxi]

Yeah, I haven't had to do that.

[jack hoxley]

I think you might need to create your palette before you can "get" it...

from my palettes tutorial:

Set DDPalette = dd.CreatePalette(DDPCAPS_8BIT Or DDPCAPS_ALLOW256, Pal())

- sure you're not ACTUALLY wanting to create the palette (fill it with the data from Pal() ), but i dont remember how DD operates internally... and I'm guessing that once you created it the GetPalette() call will just overwrite the data for you...

Secondly, work out what the automation error is telling you - it may give you the hint that you need

Jack;

[Sastraxi]

I'll try that.
This is, by the way, trying to do the same thing I had emailed you about last year.

[jack hoxley]

aah, oops

i dont really remember the questions that people email me about...

Jack;

[Sastraxi]

Thank you both for your advice, however it still gives me an Unspecified Automation Error whenever I run the code.

This really bites

Anyone have any source code of the GetPalette method in action?

[jack hoxley]

what do you mean by "Unspecified Automation Error"? you mean that you've dereferenced it to a DDERR_?? value + description, OR you're just leaving it as an automation error?

Jack;

[Sastraxi]

Do you use the GetLastError thingey to get the error or something? I remember in DirectGraphics finding the error but I don't know about DirectDraw.

God it's hard to type on this computer...

[jack hoxley]

you basically need to parse through the whole list of errors, D3DX8 makes things easy - but DD7 was quite hard

Check out this class module i 'wrote' - it'll output the description and error value.

post that back here and I/someone can maybe help you out... or it may be obvious to you straight away...

Jack;

[drewski]

I don't know if this will really help but I think I've noticed a little error in you're code, maybe.

SavePalette.GetEntries 0, 256, SavePalEntries()

The part saying "0, 256," is that supposed to mean get palette entries 0 through 256? If so that might be your problem. If you count starting with 0 then it would be 255 instead of 256.

I don't know if this'll help, but hey, it's worth a try.



Drewski

[CornedBee]

I think it is a count, not an end point. You can still try.

[Sastraxi]

Nope, thanks anyway, but the program stops before that line and it is indeed the count.