Support RGBP encoding #4414
Support RGBP encoding #4414
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| @@ -984,6 +984,13 @@ export const TEXTURETYPE_RGBM = 'rgbm'; | |||
| */ | |||
| export const TEXTURETYPE_RGBE = 'rgbe'; | |||
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| /** | |||
| * Texture stores high dynamic range data in RGBP encoding. | |||
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Wondering if some detail on the format is helpful here. Same goes for RGBM and RGBE I guess.
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Agree, will add something to the engine in a future PR.
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I created an RGBP version of a particularly problematic lightmap originally taken from https://playcanvas.com/project/345310/overview/orange-room. The result running on iphone 7: And comparison of the two lightmaps:
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Wow. I'd say that's a massive win! 😮 |
| @@ -10,6 +10,7 @@ import { | |||
| import { DebugGraphics } from './debug-graphics.js'; | |||
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| const fixCubemapSeams = true; | |||
| const RGBA8_TYPE = TEXTURETYPE_RGBM; | |||
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- local variables should not be all capital in
RGBA8_TYPE - should this default to RGBP now?
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ah this actually is a global constant .. ignore the first point :)
| srgb: 'decodeGamma', | ||
| rgbm: 'decodeRGBM', | ||
| rgbe: 'decodeRGBE' | ||
| 'linear': 'decodeLinear', |
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I think these tables should use TEXTURETYPE_RGBP and similar constants, instead of stating the strings again?
for example:
TEXTURETYPE_RGBP: 'decodeRGBP'
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So this table is actually based on texture encodings not texture types, see https://github.com/playcanvas/engine/blob/main/src/graphics/texture.js#L652
The difference between texture encoding and type is subtle and I don't like it.
Texture encoding is based on texture type and pixel format:
- texture with type 'default' and RGB8 pixels has encoding 'srgb'
- texture with type 'default' and RGB16F pixels has encoding 'linear'
- texture with type 'rgbm/rgbe/rgbp' is always encoding 'rgbm/rgbe/rgbp' no matter the pixel format.
Ideally we'd have just one enum, since it's confusing have two concepts.
(I actually added 'encoding' to texture as a helper, but it's getting used more and more).
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This looks really awesome, simple solution that solves the problem, and likely even faster to encode to! |
This PR adds support for a new HDR texture encoding (similar to RGBM).
Instead of storing pixel intensity in alpha, RGBP stores roughly
1.0 - max(1.0, pixel_intensity).This has some desirable properties, especially when stored as PNG:
For example, given this HDR image:
RGBM colour and alpha (3.6MB):
RGBP colour and alpha (3.1MB):
