This allows calls to `allocate_memory()` while the VM is running, it will then allocate from the GC heap (unless there is a suitable hole among the supervisor allocations), and when the VM exits and the GC heap is freed, the allocation will be moved to the bottom of the former GC heap and transformed into a proper supervisor allocation. Existing movable allocations will also be moved to defragment the supervisor heap and ensure that the next VM run gets as much memory as possible for the GC heap.
By itself this breaks terminalio because it violates the assumption that supervisor_display_move_memory() still has access to an undisturbed heap to copy the tilegrid from. It will work in many cases, but if you're unlucky you will get garbled terminal contents after exiting from the vm run that created the display. This will be fixed in the following commit, which is separate to simplify review.
This makes a more useful display on the portrait magtag, allowing 21
characters across instead of just 18. There are 20 full rows of text,
instead of 21. The total number of characters increases slightly from 378
to 420.
For comparison, the Commodore VIC 20 had 22 rows of 23 characters for a
total of 506 characters. :-P
Otherwise, out of range writes would occur in tilegrid_set_tile, causing a safe mode reset.
```
Hardware watchpoint 6: -location *stack_alloc->ptr
Old value = 24652061
New value = 24641565
0x000444f2 in common_hal_displayio_tilegrid_set_tile (self=0x200002c8 <supervisor_terminal_text_grid>, x=1, y=1, tile_index=0 '\000')
at ../../shared-module/displayio/TileGrid.c:236
236 if (!self->partial_change) {
(gdb)
```
The font is missing many characters and the build needs the space.
We can optimize font storage when we get a good font.
The serial output will work as usual.
This gets all the purely internal references. Some uses of
protomatter/Protomatter/PROTOMATTER remain, as they are references
to symbols in the Protomatter C library itself.
- bump supervisor alloc count by 4 (we actually use 5)
- move reconstruct to after gc heap is reset
- destroy protomatter object entirely if not used by a FramebufferDisplay
- ensure previous supervisor allocations are released
- zero out pointers so GC can collect them
This also improves Palette so it stores the original RGB888 colors.
Lastly, it adds I2CDisplay as a display bus to talk over I2C. Particularly
useful for the SSD1306.
Fixes#1828. Fixes#1956
Different operations to the display tree have different costs. Be
aware of these costs when optimizing your code.
* Changing tiles indices in a TileGrid will update an area
covering them all.
* Changing a palette will refresh every object that references it.
* Moving a TileGrid will update both where it was and where it moved to.
* Adding something to a Group will refresh each individual area it
covers.
* Removing things from a Group will refresh one area that covers all
previous locations. (Not separate areas like add.)
* Setting a new top level Group will refresh the entire display.
Only TileGrid moves are optimized for overlap. All other overlaps
cause sending of duplicate pixels.
This also adds flip_x, flip_y and transpose_xy to TileGrid. They
change the direction of the pixels but not the location.
Fixes#1169. Fixes#1705. Fixes#1923.
This changes the displayio pixel computation from per-pixel to
per-area. This is precursor work to updating portions of the screen
(#1169). It should provide mild speedups because bounds checks are
done once per area rather than once per pixel. Filling by area also
allows TileGrid to maintain a row-associative fill pattern even when
the display's refresh is orthogonal to it.
Without this, a double free can occur when a display (and terminal)
is released and then a crash occurs. Upon a second release,
different memory is released (sometimes the heap). When this is
followed by an allocation for the flash cache, the cache can
overwrite the active heap causing crashes.
Fixes#1667
This changes a number of things in displayio:
* Introduces BuiltinFont and Glyph so the built in font can be used by libraries. For boards with
a font it is available as board.TERMINAL_FONT. Fixes#1172
* Remove _load_row from Bitmap in favor of bitmap[] access. Index can be x/y tuple or overall index. Fixes#1191
* Add width and height properties to Bitmap.
* Add insert and [] access to Group. Fixes#1518
* Add index param to pop on Group.
* Terminal no longer takes unicode character info. It takes a BuiltinFont instead.
* Fix Terminal's handling of [###D vt100 commands used when up arrowing into repl history.
* Add x and y positions to Group plus scale as well.
* Add bitmap accessor for BuiltinFont
* Fix Hallowing.
* Fix builds without displayio.
* Fix y bounds that appears as untrollable row of pixels.
* Add scrolling to TileGrid.
* Remove Sprite to save space. TileGrid is a drop in replacement.
