Difference between revisions of "CompressedImageFormat"

m
m
Line 1: Line 1:
 
{{newin|[[0.9.0]]|090|type=enum}}
 
{{newin|[[0.9.0]]|090|type=enum}}
 
Compressed image data formats. [http://renderingpipeline.com/2012/07/texture-compression/ Here] and [http://www.reedbeta.com/blog/2012/02/12/understanding-bcn-texture-compression-formats/ here] are a couple overviews of many of the formats.
 
Compressed image data formats. [http://renderingpipeline.com/2012/07/texture-compression/ Here] and [http://www.reedbeta.com/blog/2012/02/12/understanding-bcn-texture-compression-formats/ here] are a couple overviews of many of the formats.
 +
 +
Unlike traditional PNG or jpeg, these formats stay compressed in RAM and in the graphics card's VRAM. This is good for saving memory space as well as improving performance, since the graphics card will be able to keep more of the image's pixels in its fast-access cache when drawing it.
 
== Constants ==
 
== Constants ==
 
;dxt1: The DXT1 format. RGB data at 4 bits per pixel (compared to 32 bits for [[ImageData]] and regular [[Image]]s.) Suitable for fully opaque images.
 
;dxt1: The DXT1 format. RGB data at 4 bits per pixel (compared to 32 bits for [[ImageData]] and regular [[Image]]s.) Suitable for fully opaque images.

Revision as of 19:55, 14 February 2014

Available since LÖVE 0.9.0
This enum is not supported in earlier versions.

Compressed image data formats. Here and here are a couple overviews of many of the formats.

Unlike traditional PNG or jpeg, these formats stay compressed in RAM and in the graphics card's VRAM. This is good for saving memory space as well as improving performance, since the graphics card will be able to keep more of the image's pixels in its fast-access cache when drawing it.

Constants

dxt1
The DXT1 format. RGB data at 4 bits per pixel (compared to 32 bits for ImageData and regular Images.) Suitable for fully opaque images.
dxt3
The DXT3 format. RGBA data at 8 bits per pixel. Smooth variations in opacity do not mix well with this format.
dxt5
The DXT5 format. RGBA data at 8 bits per pixel. Recommended for images with varying opacity.
bc4
The BC4 format (also known as 3Dc+ or ATI1.) Stores just the red channel, at 4 bits per pixel.
bc4s
The signed variant of the BC4 format. Same as above but the pixel values in the texture are in the range of [-1, 1] instead of [0, 1] in shaders.
bc5
The BC5 format (also known as 3Dc or ATI2.) Stores red and green channels at 8 bits per pixel.
bc5s
The signed variant of the BC5 format.

Notes

Not all formats are supported in love.graphics Images on all systems, although the DXT formats have close to 100% support. The BC4 and BC5 formats are supported on systems with DirectX 10 / OpenGL 3-capable hardware and drivers. Use love.graphics.isSupported to check: 

if not love.graphics.isSupported("dxt") then
    -- Can't load CompressedData with DXT formats into images!
    -- On some Linux systems with Mesa drivers, the user will need to install a "libtxc-dxtn" package because the DXT (aka S3TC) formats are patented.
    -- Support for DXT formats other than on Mesa drivers is pretty much guaranteed.
end

if not love.graphics.isSupported("bc5") then
    -- Can't load CompressedData with the BC4 and BC5 formats into images!
    -- The user likely doesn't have a video card capable of using them.
end

See Also

Other Languages

Dansk – Deutsch – English – Español – Français – Indonesia – Italiano – Lietuviškai – Magyar – Nederlands – Polski – Português – Română – Slovenský – Suomi – Svenska – Türkçe – Česky – Ελληνικά – Български – Русский – Српски – Українська – עברית – ไทย – 日本語 – 正體中文 – 简体中文 – Tiếng Việt – 한국어
More info

Retrieved from "https://love2d.org./w/index.php?title=CompressedImageFormat&oldid=13038"