I'm now extracting the concern of computing
line.screen_line_starting_pos out of Text.draw. Earlier
I had to make sure I ran through the whole line to compute
screen_line_starting_pos, but that had the side-effect of updating
Screen_bottom1.pos as well with lines that had never been rendered.
In this process I hit my first bug due to an accidental global. It
doesn't show up in the patch because I accidentally deleted a local
declaration. (I thought I didn't need screen_line_starting_pos anymore,
deleted everywhere, then brought it back everywhere from the bottom of
the function up, but forgot to put back the very first occurrence.)
The amount of yoyoing this caused between App.draw and Text.draw, I very
much have spaghetti on my hands.
Accidental globals are _terrible_ in a program with tests. Cross test
contamination X-(
I also really need to rethink how people debug my programs. My approach
of inserting and deleting print() takes a lot of commitment. I need my
old trace-based whitebox testing idea. However, in my past projects I
never did figure out a good framework for tweaking how verbose a trace
to emit.
Perhaps that's too many knobs. Perhaps we just need a way to run a
single test with the most verbose trace possible. Then it's just a
matter of having the trace tell a coherent story? But even if the trace
stays out of program output in that situation, it's still in the
programmer's face in the _code_. Ugh.
Current plan: ship program with maximum tests and zero commented-out
prints. If you want to debug, insert prints. This is better than
previous, text-mode, projects just by virtue of the stdout channel being
dedicated to debug stuff.
I have no fucking idea what I'm doing. All I know is that there's still
too many goddamn bugs[1]. Test motherfucking harness or bust. For
starters this is just the default love.run from
https://love2d.org/wiki/love.run
[1] The following file crashes if you repeatedly press cursor-down:
<<
a
b
c
```lines
```
x
>>
So far I've just changed how existing variables are organized, and put
some scaffolding in place for dealing with the new types. Next up:
rewriting the code for scrolling to something that feels more obviously
correct.
Manual test used here:
abc
```lines
{"p1":{"y":72,"x":82},"mode":"line","p2":{"y":29,"x":169}}
```
def
```lines
{"p1":{"y":36,"x":56},"mode":"line","p2":{"y":59,"x":163}}
```
```lines
```
ghi
jkl
Hitting page-down moves the cursor from abc to ghi. The 'ghi' line
should be fully visible on screen.
Still some limitations. The text cursor has to be visible on screen, so
if you have a long series of drawings without intervening lines of text
you won't be able to scroll through them all.
