feat(canvas): implement half block marker #550

joshka · 2023-09-30T04:04:28Z

A useful technique for the terminal is to use half blocks to draw a grid
of "pixels" on the screen. Because we can set two colors per cell, and
because terminal cells are about twice as tall as they are wide, we can
draw a grid of half blocks that looks like a grid of square pixels.

This commit adds a new HalfBlock marker that can be used in the Canvas
widget and the associated HalfBlockGrid.

codecov · 2023-09-30T04:07:18Z

Codecov Report

Merging #550 (c831448) into main (2fd85af) will increase coverage by 0.02%.
The diff coverage is 94.44%.

@@            Coverage Diff             @@
##             main     #550      +/-   ##
==========================================
+ Coverage   89.51%   89.53%   +0.02%     
==========================================
  Files          41       41              
  Lines       11451    11557     +106     
==========================================
+ Hits        10250    10348      +98     
- Misses       1201     1209       +8

Files	Coverage Δ
src/symbols.rs	`72.72% <ø> (ø)`
src/widgets/canvas/rectangle.rs	`99.31% <100.00%> (+0.20%)`	⬆️
src/widgets/canvas.rs	`91.38% <92.72%> (-0.52%)`	⬇️

A useful technique for the terminal is to use half blocks to draw a grid of "pixels" on the screen. Because we can set two colors per cell, and because terminal cells are about twice as tall as they are wide, we can draw a grid of half blocks that looks like a grid of square pixels. This commit adds a new `HalfBlock` marker that can be used in the Canvas widget and the associated HalfBlockGrid. Also updated demo2 to use the new marker as it looks much nicer.

src/widgets/canvas.rs

correct the error in my understanding of the coordinate systems, change halfblock cells to pixels, update demo2, document the half block algorithm

src/widgets/canvas.rs

joshka · 2023-09-30T07:36:15Z

Comments addressed in c831448

kdheepak · 2023-09-30T08:09:50Z

Awesome! Excited to see what people make with this!

* feat(canvas): implement half block marker A useful technique for the terminal is to use half blocks to draw a grid of "pixels" on the screen. Because we can set two colors per cell, and because terminal cells are about twice as tall as they are wide, we can draw a grid of half blocks that looks like a grid of square pixels. This commit adds a new `HalfBlock` marker that can be used in the Canvas widget and the associated HalfBlockGrid. Also updated demo2 to use the new marker as it looks much nicer. Adds docs for many of the methods and structs on canvas. Changes the grid resolution method to return the pixel count rather than the index of the last pixel. This is an internal detail with no user impact.

joshka requested review from orhun, mindoodoo, sayanarijit, sophacles and kdheepak as code owners September 30, 2023 04:04

joshka force-pushed the canvas-half-block branch from be56df3 to 92e024b Compare September 30, 2023 04:18