[fpc-pascal] Loading PNG files as OpenGL textures

[Michael Van Canneyt]

On Wed, 14 Oct 2015, Ryan Joseph wrote:

>
>> On Oct 12, 2015, at 2:25 PM, Michael Van Canneyt <michael at freepascal.org> wrote:
>> 
>> TFPCustomImage is an abstract image class, it provides no storage for the data. It can have several descendants such as TFPMemoryImage and TFPCompactImgRGBA8Bit.
>> If you just want the raw data, create a TFPMemoryImage and access the Colors array property.
>
> Sorry for the silence.
>
> I’ve learned that the FPImage classes are pretty slow but I’d like to try them anyways first to see if they’re acceptable.
>
> I don’t use Delphi so the FPC docs are a little confusing for me. There is a colors/pixels property but from what I can tell they map to getting a single pixel/color at a specific location, but the docs aren’t clear because the method arguments are never shown. 
>
> Do I need to loop through all the pixels or something and pack them into a
> pointer?  There should be some a single continuous block of memory in this
> class but I can’t seem to find it using the colors/pixels property.  What
> am I missing?

Your are not missing anything, you saw correct.
TFPCompactImgRGBA8Bit is probably what you need, you'll need to subclass it to get direct access to the
   FData: PFPCompactImgRGBA8BitValue; 
field, which is the memory buffer.

Michael.