libvaxis/src/InternalScreen.zig
Tim Culverhouse a0db41f87c render: add cli renderer
Add a renderer for applications running on the primary screen. This
renderer uses relative cursor positioning, and works with all the same
primitives as the alternate screen.

Fix a bug where repositioning was never turned back to false. This was a
nasty one with huge perf implications.

Set internal cells to a space and default on init. This prevents us from
writing them. As a result, we now issue a hardware clear on resize.
2024-05-02 12:50:33 -05:00

123 lines
3.6 KiB
Zig

const std = @import("std");
const assert = std.debug.assert;
const Style = @import("Cell.zig").Style;
const Cell = @import("Cell.zig");
const MouseShape = @import("Mouse.zig").Shape;
const CursorShape = Cell.CursorShape;
const log = std.log.scoped(.internal_screen);
const InternalScreen = @This();
pub const InternalCell = struct {
char: std.ArrayList(u8) = undefined,
style: Style = .{},
uri: std.ArrayList(u8) = undefined,
uri_id: std.ArrayList(u8) = undefined,
// if we got skipped because of a wide character
skipped: bool = false,
default: bool = true,
pub fn eql(self: InternalCell, cell: Cell) bool {
// fastpath when both cells are default
if (self.default and cell.default) return true;
// this is actually faster than std.meta.eql on the individual items.
// Our strings are always small, usually less than 4 bytes so the simd
// usage in std.mem.eql has too much overhead vs looping the bytes
if (!std.mem.eql(u8, self.char.items, cell.char.grapheme)) return false;
if (!Style.eql(self.style, cell.style)) return false;
if (!std.mem.eql(u8, self.uri.items, cell.link.uri)) return false;
if (!std.mem.eql(u8, self.uri_id.items, cell.link.params)) return false;
return true;
}
};
width: usize = 0,
height: usize = 0,
buf: []InternalCell = undefined,
cursor_row: usize = 0,
cursor_col: usize = 0,
cursor_vis: bool = false,
cursor_shape: CursorShape = .default,
mouse_shape: MouseShape = .default,
/// sets each cell to the default cell
pub fn init(alloc: std.mem.Allocator, w: usize, h: usize) !InternalScreen {
var screen = InternalScreen{
.buf = try alloc.alloc(InternalCell, w * h),
};
for (screen.buf, 0..) |_, i| {
screen.buf[i] = .{
.char = try std.ArrayList(u8).initCapacity(alloc, 1),
.uri = std.ArrayList(u8).init(alloc),
.uri_id = std.ArrayList(u8).init(alloc),
};
try screen.buf[i].char.append(' ');
}
screen.width = w;
screen.height = h;
return screen;
}
pub fn deinit(self: *InternalScreen, alloc: std.mem.Allocator) void {
for (self.buf, 0..) |_, i| {
self.buf[i].char.deinit();
self.buf[i].uri.deinit();
self.buf[i].uri_id.deinit();
}
alloc.free(self.buf);
}
/// writes a cell to a location. 0 indexed
pub fn writeCell(
self: *InternalScreen,
col: usize,
row: usize,
cell: Cell,
) void {
if (self.width < col) {
// column out of bounds
return;
}
if (self.height < row) {
// height out of bounds
return;
}
const i = (row * self.width) + col;
assert(i < self.buf.len);
self.buf[i].char.clearRetainingCapacity();
self.buf[i].char.appendSlice(cell.char.grapheme) catch {
log.warn("couldn't write grapheme", .{});
};
self.buf[i].uri.clearRetainingCapacity();
self.buf[i].uri.appendSlice(cell.link.uri) catch {
log.warn("couldn't write uri", .{});
};
self.buf[i].uri_id.clearRetainingCapacity();
self.buf[i].uri_id.appendSlice(cell.link.params) catch {
log.warn("couldn't write uri_id", .{});
};
self.buf[i].style = cell.style;
self.buf[i].default = cell.default;
}
pub fn readCell(self: *InternalScreen, col: usize, row: usize) ?Cell {
if (self.width < col) {
// column out of bounds
return null;
}
if (self.height < row) {
// height out of bounds
return null;
}
const i = (row * self.width) + col;
assert(i < self.buf.len);
return .{
.char = .{ .grapheme = self.buf[i].char.items },
.style = self.buf[i].style,
};
}