AmigaFFH: rawToHWSprite – R documentation

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rawToHWSprite

Convert raw data into an Amiga hardware sprite

Description

Convert raw data structured conform a Commodore Amiga hardware sprite (see references) into a hardwareSprite object.

Usage

## S4 method for signature 'raw,missing'
rawToHWSprite(x, col)

## S4 method for signature 'raw,character'
rawToHWSprite(x, col)

Arguments

`x`	`raw` data structured as an Amiga hardware sprite (see references).
`col`	A `vector` of colours (`character`) to be used for the hardware sprite. Specify the three visible colours for the sprite. When missing some default colours (grayscale) will be used. The colours have to be provided separately as they are usually not stored together with the hardware sprite data.

Details

Information to set up a hardware sprite is stored as raw data on Commodore Amigas. This method can be used to convert this data into a hardwareSprite object. This object can in turn be converted with as.raster such that it can be plotted in R.

Value

Returns a hardwareSprite object based on the provided raw data

Author(s)

Pepijn de Vries

References

http://amigadev.elowar.com/read/ADCD_2.1/Hardware_Manual_guide/node00B9.html

Examples

## Let's generate a 16x16 sprite with a random bitmap:
dat <- as.raw(c(0x00, 0x00, 0x10, 0x00,
              sample.int(255, 64, replace = TRUE),
              0x00, 0x00, 0x00, 0x00))
## make it a hardware sprite object:
spr <- rawToHWSprite(dat)
## and plot it:
plot(spr, interpolate = FALSE)

## with some imagination when can make
## a more structured image:
dat <- as.raw(c(0x00, 0x00, 0x10, 0x00, 0x00, 0x00, 0xff, 0xf8,
                0x7f, 0x80, 0x80, 0x70, 0x7f, 0x00, 0xbe, 0xe0,
                0x7e, 0x00, 0x85, 0xc0, 0x7d, 0x80, 0x82, 0x40,
                0x6b, 0xc0, 0x95, 0xa0, 0x57, 0xe0, 0xa8, 0xd0,
                0x2f, 0xf0, 0xd1, 0x68, 0x4f, 0xf8, 0xb0, 0x34,
                0x07, 0xfc, 0xf8, 0x5a, 0x03, 0xfe, 0xe4, 0x0d,
                0x01, 0xfc, 0xc2, 0x12, 0x00, 0xf8, 0x81, 0x04,
                0x00, 0x70, 0x00, 0x88, 0x00, 0x20, 0x00, 0x50,
                0x00, 0x00, 0x00, 0x20, 0x00, 0x00, 0x00, 0x00))
spr <- rawToHWSprite(dat, c("#EE4444", "#000000", "#EEEECC"))
plot(spr, interpolate = FALSE)

AmigaFFH

Commodore Amiga File Format Handler

v0.3.1

GPL-3

Authors

Pepijn de Vries [aut, cre, dtc]

Initial release

2019-03-31