program parameter current limitations

[fabrobinet]

Currently a parameter has types such as SAMPLER_2D , FLOAT_VEC etc...

SAMPLER_2D currently has an image property, it is too naive. we need to change this, we want to handle video too.

Some more aspects to discuss:

• We also want to be able to declare samplers not tied to an image for offscreen rendering.
• Additionally, how will we declare cube maps ? for the type it's easy, there is SAMPLER_CUBE. For the 6 images, let's see where they would fit...

During last discussion Remi proposed to bring back the surface concept from COLLADA.

• it's a good place to specify width/height for offscreen rendering
• It looks appropriate to declare the 6 images required for CUBE_MAP
• within the surface we could have a "source" property that would be to either a uniqueID which can be an image or a video (that's close to Remi proposal too, but that wouldn't be a path directly). when the type of surface would be cube we would have a "sources" property that would take an array of 6 unique IDs. (like for image&video).
  In surface, "source" would have a different meaning than in COLLADA but I believe it wouldn't be confusing.

Also, currently parameter short-cut the indirection that COLLADA has for sampler.
And so far it looks fine this way.

I believe we should give a try at adding surface.
I'll attach soon a JSON example here.

[RemiArnaud]

FYI - here's what cubemap defined as 6 images looks like in collada

    <newparam sid="_3246-surface">
      <semantic>Cube</semantic>
      <surface type="CUBE">
        <init_from>_3246_0</init_from>
        <init_from face="NEGATIVE_X">_3246_1</init_from>
        <init_from face="POSITIVE_Y">_3246_2</init_from>
        <init_from face="NEGATIVE_Y">_3246_3</init_from>
        <init_from face="POSITIVE_Z">_3246_4</init_from>
        <init_from face="NEGATIVE_Z">_3246_5</init_from>
        <format>R8G8B8</format>
      </surface>
    </newparam>

Also possible to define as 1 image.
Note that this is also useful to define individual files per mip-map...
(also see the format parameter, which is quite standardized even if not
fully specified in the COLLADA spec).

[pjcozzi]

I'll attach soon a JSON example here.

If you have an example, I'm happy to provide input. Or should we expect to see this as part of your larger FX work?

[pjcozzi]

Is this duplicate with #40?

[fabrobinet]

yes it is. closing.