Scripted Textures

[Marisa the Magician]

Interest for this kind of thing has resurfaced again. You may remember the horrendous hack that was phantombeta implementing the psx fire as a camera texture displaying a grid of sectors changing color. Someone really needs to put an end to this madness and actually make this. I don't know if I could, though, it sounds like such a monumental task and I don't have enough time to work on anything like that. The way I'm thinking about it would involve moving all the 2d drawing code back to the DCanvas class, then make it so the Screen.* API works on instances of it rather than on the global screen framebuffer (which would be moved to the zscript globals, for backwards compatibility). Obviously ANIMDEFS would have to be expanded for creating these, just like it does for camera textures.

There really shouldn't be any concerns over performance when it comes to this, since we'd be using the renderer's own facilities for drawing, rather than working on raw pixels.

[Graf Zahl]

Forget the canvas, that part will never work. The 2D drawing is completely hardware accelerated, the canvas is just a software buffer.

This is certainly doable but will require quite a bit of backend work - and if you want software renderer support some exporting facility of the created texture

[Marisa the Magician]

OK, massive frustration with a gross hack involving camera textures not working properly depending on the map has forced me to bump this thread. WE ABSOLUTELY NEED THIS.

[Graf Zahl]

We need *what*? You got to be a bit more precise about your intents.

[Nash]

I think what Marisa is saying is that people have been abusing camera textures to approximate scriptable textures (with varying degrees of success) and we all know what happens when features are used in ways they're not designed to do, therefore she's suggesting proper, Unreal Engine-style scriptable textures.

[Graf Zahl]

The suggestion says "scriptable canvas texture', so this needs clarification.

[Rachael]

I think a better name for this thread would be "Scriptable Textures" - which would work for both canvas and materials (i.e. object or geometry textures).

[Marisa the Magician]

Changed the thread title.

What I'm proposing, in simpler terms, is textures that can be drawn to from ZScript, like one would do drawing on the screen itself.

[Marisa the Magician]

Well, it's been some time, but I guess this one can be closed as [Added].

Absolutely huge thanks to dpJudas for making the dream come true.

[Gez]

So, technically, could the PSX fire sky be implemented this way now? What would the code look like?

[Marisa the Magician]

Probably a lot of calls to drawtexture with a 1x1 pixel texture.

[Graf Zahl]

ZScript may be too slow to do textures that are programmatically generated per pixel. Even in the best of cases it may be too slow even with JIT due to all the range checks

[Rachael]

For per-pixel we can reduce range checks to one check by allowing a special per-pixel texelation command to have a single one-dimensional addressing scheme which will access the entire texture. That should increase the speed of per-texel scripting a little bit. Bonus: cast it to an unsigned integer to reduce the checking even further since negatives will then always fail the check.

[Major Cooke]

And out of curiosity, how does one do this now? I'd love to see an example!

Or the main functions can work.

[Nash]

From the pull request thread by dpJudas:

This adds support for creating canvas textures in ANIMDEFS using same syntax as for camera textures (except the keyword is canvastexture instead).

On the zscript side the texture can be drawn into using the following method:

Code: Select all

Canvas canvas = TexMan.GetCanvas("mycanvastexture");
canvas.Clear(0, 0, 64, 128, Screen.PaletteColor(123));
canvas.DrawText(bigfont, Font.CR_ORANGE, 0, 0, "HELLO!");