A simple backbuffer for preparing cli-output before actually outputting it all at once.
PHP Version 8.2
To test the cli backbuffer in general, an integration test just inputs a lorem ipsum and emojis into it and outputs everything while measuring the individual durations for every task.
Please note: The display of emojis in Terminal is inconsistend and WILL seemingly overflow the line, until you copy the text and measure it in a text-editor to see, that there is no overflow, just a display bug. Emojis are used to fit UTF-8 compatibility.
$ php ./cli_test_backbuffer_integration_performance.php
To just directly look at the flames, start the animation effect flame test (you may have to manually adjust the size of the backbuffer in line 10).
$ php ./cli_test_animation_effect_flame.php
The CLIAnimationEngine takes an CLIAnimationEffect and a CLIBackbuffer for repeatedly creating frames.
CLIAnimationEffect will then procedurally generate frames by consecutively calculating over the last round's values.
CLIBackbuffer gets filled by CLIAnimationEffect exactly once per frame outputting the full diplay page as a long string which gets outputted to the terminal.
My heartpiece of the project.
constructor the constructor takes the size of the terminal to buffer with x_cols and y_rows.
Furthermore you can give a prefill_char to prefill the buffer with; otherwise it will be prefilled with {empty string}.
CLIBackbuffer has a map (assoc-array) of all 2-dimensional values in 1 dimension (by making the keys 2-dimensional).
makeInternalIdx is used to build these keys by inserting x and y coordinates
getPos gives an assoc-array with ['x'] and ['y'] coordinates of the virtual write-cursor as int.
setPos sets the cursor position for writing.
writeChar writes a char at the given cursor position (not automatically advancing forward).
writeString writes a string at the given cursor position advancing the cursor forward, advancing lines forward.
breakline moves the cursor to the beginning of the next line.
writeLine combines writeString with breakline.
writeout returns the backbuffers content as a string.
getRemCharsRow returns the count of available chars in the current row as seen from the current cursor position.
placeChar places a char at a specific location not touching the cursor position.
A simple motivator for the CliAnimationEffect to run continously.
constructor takes a backbuffer and an effect to orchestrate.
outputNextFrame does everything necessary to get the next frame going:
Uses the effect to calculate a new frame, clear the terminal and output the buffer.
runForever just consecutively generates frames for your viewing pleasure.
CLIAnimationEffect is an abstract class to shim other different effects into the same behaviour of having a renderNextFrame function and a FRAME_DELAY_MS constant.
This code is mostly ported and unobfuscated from javascript and modified to use my backbuffer instead of the JS-window-Element.