Keep Screen (screen.keep)

Declaration

screen.keep()

Description

Cache the current screen image into a buffer. When calling color picking, color finding, screenshot, image finding functions multiple times, data will be read from the cached buffer instead of the live screen, improving performance.
This is an optimization function for heavy static image processing.
It ONLY affects XXTouch's capture/color functions and does NOT freeze the actual device screen.

Example

-- Loop and sample colors of 6144 points, output to log
t = {}
screen.keep()
for k = 1, 640, 10 do
    for j = 1, 960, 10 do
        -- format as hex string
        t[#t + 1] = string.format("%X", screen.get_color(k, j))
    end
end
screen.unkeep()
nLog(t)

Note: Uses nLog

Notes

• Two consecutive separate screen.get_color calls on the same position may get different values.
• Without screen.keep, a single screen.get_color call costs about the same as one screen.keep.
• After screen.keep, about 50 consecutive screen.get_color calls cost about the same as one screen.keep.