-
-
Notifications
You must be signed in to change notification settings - Fork 109
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
- Loading branch information
1 parent
031a45f
commit f6d63f9
Showing
42 changed files
with
2,523 additions
and
2,334 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,89 @@ | ||
# Grid (re)design | ||
|
||
## grid properties | ||
|
||
- line and column positions are given in offsets (0-based indices!) | ||
- grid cells of the full scrollback + main page area are stored in dense linear space | ||
- `Line` is just a view into the ring buffer | ||
- logical lines above main page area's line count cannot be edited | ||
- scroll offset represents the *bottom* line of the viewport. | ||
- maybe make scroll offset negative (to have all ops being additions) | ||
|
||
## corollary | ||
|
||
- the VT screen line/column position to offset translation (minus 1) | ||
happens as early as possible in the `Sequencer`. | ||
- `Line::Wrapped`-flag can be removed. | ||
- writing an overlong line does not need to care about auto-wrapping | ||
- because `lineLength / pageWidth == numberOfLinesWriten` | ||
- the new cursor position can be computed analogous to the above | ||
- because of the meaning of the scroll-offset, reflow can be O(1) implemented | ||
with a `Line()` being arbitrary long(!) and the top screen line being | ||
computed by subtracting `(PageLineCount - 1) * PageColumnCount)`, | ||
then *just* lineary walking forward until the bottom right. | ||
- this enables relative jumps (`CUU` etc) to jump up logical lines. | ||
- we could make the cursor jump behavior configurable, via DEC mode. | ||
- On char write overflow | ||
- if Reflow DEC mode is enabled, then continue appending character | ||
- else if AutoWrap DEC mode is enabled, then linefeed() | ||
- else overwrite character on right margin | ||
- I think with the above approach we do not need DEC mode 2027 for disabling | ||
reflow in order to protect command prompts. as they're automatically protected | ||
by the grid line architecture. | ||
|
||
### Notes | ||
|
||
Suppose only a single overly long line is written and ocupies the full screen | ||
(many page counts). | ||
|
||
``` | ||
bottomRightOffset = line(cursor.line + realOffset(scrollOffset_)).right_offset; | ||
topLeftOffset = bottomRightOffset - pageSize.lines * pageSize.columns; | ||
def renderViewport(): | ||
{ | ||
for (auto i = topLeftOffset, k = 0; i < bottomRightOffset; ++i, ++k) | ||
{ | ||
auto rowNr = k / pageSize.columns; | ||
auto colNr = k % pageSize.columns; | ||
renderCell(buffer_[i], rowNr, colNr); | ||
} | ||
} | ||
``` | ||
|
||
## shrink columns | ||
|
||
page size: 6x2 | ||
lines: 2 | ||
line.1: 0..5 abcdef | ||
line.2: 6..11 ABCDEF | ||
|
||
shrink to pageSize: 4x2 | ||
|
||
line.1: 0..3 abcd | ||
line.2: 4..5 ef Wrapped | ||
line.3: 6..9 ABCD | ||
line.4: 10..11 EF Wrapped | ||
|
||
Shrinking does not destroy, as it always reflows. | ||
`CUU` will move by logical line numbers. | ||
|
||
## overlong lines | ||
|
||
4x2 | ||
|
||
|
||
line.1 ABCDEFabcdef | ||
line.2 ABCD | ||
|
||
view: | ||
|
||
history.line.-1 ABCD | ||
history.line.0 EFAB | ||
logical.line.1 cdef | ||
logical.line.2 ABCD | ||
|
||
## Rendering a wrapped line | ||
|
||
- the scroll-offset represents the number of real lines scrolled up | ||
- |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Oops, something went wrong.