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Merged
forketyfork merged 3 commits into from
Mar 4, 2026
Merged

fix(terminal): forward mouse clicks to PTY and render underlines #251

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35fe633
fix(terminal): forward mouse clicks to PTY and render underlines
forketyfork Mar 4, 2026
50db732
chore: update setup script to run direnv allow
forketyfork Mar 4, 2026
fe1a4c5
fix(terminal): address review feedback on mouse encoding and underlin…
forketyfork Mar 4, 2026
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2 changes: 1 addition & 1 deletion script/setup
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Original file line number Diff line number Diff line change
@@ -1,3 +1,3 @@
#!/bin/sh

echo "Hello from custom script"
direnv allow
5 changes: 5 additions & 0 deletions src/c.zig
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Original file line number Diff line number Diff line change
Expand Up @@ -96,6 +96,11 @@ pub const SDL_EVENT_DROP_COMPLETE = c_import.SDL_EVENT_DROP_COMPLETE;
pub const SDL_EVENT_DROP_POSITION = c_import.SDL_EVENT_DROP_POSITION;
pub const SDL_TOUCH_MOUSEID = c_import.SDL_TOUCH_MOUSEID;
pub const SDL_BUTTON_LEFT: c_import.Uint8 = c_import.SDL_BUTTON_LEFT;
pub const SDL_BUTTON_MIDDLE: c_import.Uint8 = c_import.SDL_BUTTON_MIDDLE;
pub const SDL_BUTTON_RIGHT: c_import.Uint8 = c_import.SDL_BUTTON_RIGHT;
pub const SDL_BUTTON_LMASK: c_import.SDL_MouseButtonFlags = c_import.SDL_BUTTON_LMASK;
pub const SDL_BUTTON_MMASK: c_import.SDL_MouseButtonFlags = c_import.SDL_BUTTON_MMASK;
pub const SDL_BUTTON_RMASK: c_import.SDL_MouseButtonFlags = c_import.SDL_BUTTON_RMASK;
pub const SDL_SYSTEM_CURSOR_DEFAULT = c_import.SDL_SYSTEM_CURSOR_DEFAULT;
pub const SDL_SYSTEM_CURSOR_TEXT = c_import.SDL_SYSTEM_CURSOR_TEXT;
pub const SDL_SYSTEM_CURSOR_POINTER = c_import.SDL_SYSTEM_CURSOR_POINTER;
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118 changes: 118 additions & 0 deletions src/input/mapper.zig
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Expand Up @@ -578,6 +578,124 @@ test "encodeMouseScroll - scroll down X10 with position" {
try std.testing.expectEqual(@as(u8, 5 + 33), buf[5]); // row + 33
}

pub const MouseButton = enum(u8) { left = 0, middle = 1, right = 2 };

/// Encodes a mouse button press or release event for terminal mouse tracking.
/// SGR format: CSI < button ; col ; row M (press) or m (release). 1-based coordinates.
/// X10 format: CSI M <button+32> <col+33> <row+33>. Release uses button code 3.
pub fn encodeMouseButton(
button: MouseButton,
col: u16,
row: u16,
press: bool,
sgr_format: bool,
buf: []u8,
) usize {
const btn: u8 = @intFromEnum(button);

if (sgr_format) {
const suffix: u8 = if (press) 'M' else 'm';
const result = std.fmt.bufPrint(buf, "\x1b[<{d};{d};{d}{c}", .{ btn, col + 1, row + 1, suffix }) catch return 0;
return result.len;
} else {
const x10_btn: u8 = if (press) btn else 3; // 3 = release indicator in X10
const x10_offset: u16 = 33;
const x10_coord_max: u16 = 255 - x10_offset;
const x = @min(col, x10_coord_max) + x10_offset;
const y = @min(row, x10_coord_max) + x10_offset;
if (buf.len < 6) return 0;
buf[0] = '\x1b';
buf[1] = '[';
buf[2] = 'M';
buf[3] = x10_btn + 32;
buf[4] = @intCast(x);
buf[5] = @intCast(y);
return 6;
}
}

/// Encodes a mouse motion event for terminal mouse tracking.
/// Motion uses button code + 32 (the motion flag). Button code 3 means no button held.
/// SGR format: CSI < code ; col ; row M. X10 format: CSI M <code+32> <col+33> <row+33>.
pub fn encodeMouseMotion(
button: ?MouseButton,
col: u16,
row: u16,
sgr_format: bool,
buf: []u8,
) usize {
const base: u8 = if (button) |b| @intFromEnum(b) else 3; // 3 = no button
const code: u8 = base + 32; // motion flag

if (sgr_format) {
const result = std.fmt.bufPrint(buf, "\x1b[<{d};{d};{d}M", .{ code, col + 1, row + 1 }) catch return 0;
return result.len;
} else {
const x10_offset: u16 = 33;
const x10_coord_max: u16 = 255 - x10_offset;
const x = @min(col, x10_coord_max) + x10_offset;
const y = @min(row, x10_coord_max) + x10_offset;
if (buf.len < 6) return 0;
buf[0] = '\x1b';
buf[1] = '[';
buf[2] = 'M';
buf[3] = code + 32;
buf[4] = @intCast(x);
buf[5] = @intCast(y);
return 6;
}
}

test "encodeMouseButton - left press SGR" {
var buf: [32]u8 = undefined;
const n = encodeMouseButton(.left, 5, 3, true, true, &buf);
try std.testing.expectEqualSlices(u8, "\x1b[<0;6;4M", buf[0..n]);
}

test "encodeMouseButton - left release SGR" {
var buf: [32]u8 = undefined;
const n = encodeMouseButton(.left, 5, 3, false, true, &buf);
try std.testing.expectEqualSlices(u8, "\x1b[<0;6;4m", buf[0..n]);
}

test "encodeMouseButton - right press SGR" {
var buf: [32]u8 = undefined;
const n = encodeMouseButton(.right, 0, 0, true, true, &buf);
try std.testing.expectEqualSlices(u8, "\x1b[<2;1;1M", buf[0..n]);
}

test "encodeMouseButton - left press X10" {
var buf: [32]u8 = undefined;
const n = encodeMouseButton(.left, 5, 3, true, false, &buf);
try std.testing.expectEqual(@as(usize, 6), n);
try std.testing.expectEqualSlices(u8, "\x1b[M", buf[0..3]);
try std.testing.expectEqual(@as(u8, 0 + 32), buf[3]);
try std.testing.expectEqual(@as(u8, 5 + 33), buf[4]);
try std.testing.expectEqual(@as(u8, 3 + 33), buf[5]);
}

test "encodeMouseButton - release X10 sends button 3" {
var buf: [32]u8 = undefined;
const n = encodeMouseButton(.left, 5, 3, false, false, &buf);
try std.testing.expectEqual(@as(usize, 6), n);
try std.testing.expectEqualSlices(u8, "\x1b[M", buf[0..3]);
try std.testing.expectEqual(@as(u8, 3 + 32), buf[3]); // release = button 3
try std.testing.expectEqual(@as(u8, 5 + 33), buf[4]);
try std.testing.expectEqual(@as(u8, 3 + 33), buf[5]);
}

test "encodeMouseMotion - no button SGR" {
var buf: [32]u8 = undefined;
const n = encodeMouseMotion(null, 10, 5, true, &buf);
try std.testing.expectEqualSlices(u8, "\x1b[<35;11;6M", buf[0..n]);
}

test "encodeMouseMotion - left button held SGR" {
var buf: [32]u8 = undefined;
const n = encodeMouseMotion(.left, 2, 1, true, &buf);
try std.testing.expectEqualSlices(u8, "\x1b[<32;3;2M", buf[0..n]);
}

test "terminalSwitchShortcut - cmd+1 returns 0" {
try std.testing.expectEqual(@as(?usize, 0), terminalSwitchShortcut(c.SDLK_1, c.SDL_KMOD_GUI, 9));
}
Expand Down
18 changes: 18 additions & 0 deletions src/render/renderer.zig
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Original file line number Diff line number Diff line change
Expand Up @@ -396,6 +396,9 @@ fn renderSessionContent(
var run_width_cells: c_int = 0;
var run_variant: FontVariant = .regular;

var underline_count: usize = 0;
var underline_segments: [256]struct { x_start: f32, x_end: f32, y_pos: f32, color: c.SDL_Color } = undefined;

var col: usize = 0;
while (col < visible_cols) : (col += 1) {
const list_cell = pages.getCell(if (view.is_viewing_scrollback)
Expand Down Expand Up @@ -491,6 +494,16 @@ fn renderSessionContent(
}
}

if (style.flags.underline != .none and underline_count < underline_segments.len) {
underline_segments[underline_count] = .{
.x_start = @floatFromInt(x),
.x_end = @floatFromInt(x + eff_cw * glyph_width_cells - 1),
.y_pos = @floatFromInt(y + eff_ch - 1),
.color = fg_color,
};
underline_count += 1;
}

const is_box_drawing = cp != 0 and cp != ' ' and !style.flags.invisible and renderBoxDrawing(renderer, cp, x, y, eff_cw, eff_ch, fg_color);
if (is_box_drawing) {
try flushRun(font, run_buf[0..], run_len, run_x, y, run_cells, eff_cw, eff_ch, run_fg, run_variant);
Expand Down Expand Up @@ -585,6 +598,11 @@ fn renderSessionContent(
}

try flushRun(font, run_buf[0..], run_len, run_x, origin_y + @as(c_int, @intCast(row)) * cell_height_actual, run_cells, eff_cw, eff_ch, run_fg, run_variant);

for (underline_segments[0..underline_count]) |seg| {
_ = c.SDL_SetRenderDrawColor(renderer, seg.color.r, seg.color.g, seg.color.b, 255);
_ = c.SDL_RenderLine(renderer, seg.x_start, seg.y_pos, seg.x_end, seg.y_pos);
}
}

if (session.dead) {
Expand Down
138 changes: 116 additions & 22 deletions src/ui/components/session_interaction.zig
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Original file line number Diff line number Diff line change
Expand Up @@ -186,36 +186,55 @@ pub const SessionInteractionComponent = struct {
return true;
}

if (host.view_mode == .Full and event.button.button == c.SDL_BUTTON_LEFT) {
if (host.view_mode == .Full) {
const focused_idx = host.focused_session;
if (focused_idx >= self.sessions.len) return false;
const focused = self.sessions[focused_idx];
const view = &self.views[focused_idx];

if (focused.spawned and focused.terminal != null) {
if (fullViewPinFromMouse(focused, view, mouse_x, mouse_y, host.window_w, host.window_h, self.font, host.term_cols, host.term_rows, host.ui_scale)) |pin| {
const clicks = event.button.clicks;
if (clicks >= 3) {
selectLine(focused, view, pin);
} else if (clicks == 2) {
selectWord(focused, view, pin);
} else {
const mod = c.SDL_GetModState();
const cmd_held = (mod & c.SDL_KMOD_GUI) != 0;
if (cmd_held) {
if (getLinkAtPin(self.allocator, &focused.terminal.?, pin, view.is_viewing_scrollback)) |uri| {
defer self.allocator.free(uri);
open_url.openUrl(self.allocator, uri) catch |err| {
log.err("failed to open URL: {}", .{err});
const terminal = &focused.terminal.?;
if (terminalHasMouseTracking(terminal) and !view.is_viewing_scrollback) {
if (sdlToMouseButton(event.button.button)) |btn| {
if (fullViewCellFromMouse(mouse_x, mouse_y, host.window_w, host.window_h, self.font, host.term_cols, host.term_rows, host.ui_scale)) |cell| {
const sgr = terminal.modes.get(.mouse_format_sgr);
var buf: [32]u8 = undefined;
const n = input.encodeMouseButton(btn, cell.col, cell.row, true, sgr, &buf);
if (n > 0) {
focused.sendInput(buf[0..n]) catch |err| {
log.warn("failed to send mouse button: {}", .{err});
};
}
return true;
}
}
}

if (event.button.button == c.SDL_BUTTON_LEFT) {
if (fullViewPinFromMouse(focused, view, mouse_x, mouse_y, host.window_w, host.window_h, self.font, host.term_cols, host.term_rows, host.ui_scale)) |pin| {
const clicks = event.button.clicks;
if (clicks >= 3) {
selectLine(focused, view, pin);
} else if (clicks == 2) {
selectWord(focused, view, pin);
} else {
const mod = c.SDL_GetModState();
const cmd_held = (mod & c.SDL_KMOD_GUI) != 0;
if (cmd_held) {
if (getLinkAtPin(self.allocator, &focused.terminal.?, pin, view.is_viewing_scrollback)) |uri| {
defer self.allocator.free(uri);
open_url.openUrl(self.allocator, uri) catch |err| {
log.err("failed to open URL: {}", .{err});
};
} else {
beginSelection(focused, view, pin);
}
} else {
beginSelection(focused, view, pin);
}
} else {
beginSelection(focused, view, pin);
}
return true;
}
return true;
}
}
}
Expand All @@ -224,11 +243,38 @@ pub const SessionInteractionComponent = struct {
if (event.button.button == c.SDL_BUTTON_LEFT and self.finishTerminalScrollbarDrag(host.now_ms)) {
return true;
}
if (host.view_mode == .Full and event.button.button == c.SDL_BUTTON_LEFT) {
if (host.view_mode == .Full) {
const focused_idx = host.focused_session;
if (focused_idx >= self.views.len) return false;
endSelection(&self.views[focused_idx]);
return true;
if (focused_idx >= self.sessions.len) return false;
const focused = self.sessions[focused_idx];
const view = &self.views[focused_idx];

if (focused.spawned and focused.terminal != null) {
const terminal = &focused.terminal.?;
if (terminalHasMouseTracking(terminal) and !view.is_viewing_scrollback) {
if (sdlToMouseButton(event.button.button)) |btn| {
const mouse_x: c_int = @intFromFloat(event.button.x);
const mouse_y: c_int = @intFromFloat(event.button.y);
if (fullViewCellFromMouse(mouse_x, mouse_y, host.window_w, host.window_h, self.font, host.term_cols, host.term_rows, host.ui_scale)) |cell| {
const sgr = terminal.modes.get(.mouse_format_sgr);
var buf: [32]u8 = undefined;
const n = input.encodeMouseButton(btn, cell.col, cell.row, false, sgr, &buf);
if (n > 0) {
focused.sendInput(buf[0..n]) catch |err| {
log.warn("failed to send mouse release: {}", .{err});
};
}
return true;
}
}
}
}

if (event.button.button == c.SDL_BUTTON_LEFT) {
if (focused_idx >= self.views.len) return false;
endSelection(&self.views[focused_idx]);
return true;
}
}
},
c.SDL_EVENT_MOUSE_MOTION => {
Expand All @@ -244,6 +290,38 @@ pub const SessionInteractionComponent = struct {
if (focused_idx < self.sessions.len) {
var focused = self.sessions[focused_idx];
const view = &self.views[focused_idx];

if (focused.spawned and focused.terminal != null and !view.is_viewing_scrollback) {
const terminal = &focused.terminal.?;
const any_tracking = terminal.modes.get(.mouse_event_any);
const btn_tracking = terminal.modes.get(.mouse_event_button);
const btn_held = (event.motion.state & c.SDL_BUTTON_LMASK) != 0 or
(event.motion.state & c.SDL_BUTTON_MMASK) != 0 or
(event.motion.state & c.SDL_BUTTON_RMASK) != 0;
if (any_tracking or (btn_tracking and btn_held)) {
if (fullViewCellFromMouse(mouse_x, mouse_y, host.window_w, host.window_h, self.font, host.term_cols, host.term_rows, host.ui_scale)) |cell| {
const held_btn: ?input.MouseButton = if ((event.motion.state & c.SDL_BUTTON_LMASK) != 0)
.left
else if ((event.motion.state & c.SDL_BUTTON_MMASK) != 0)
.middle
else if ((event.motion.state & c.SDL_BUTTON_RMASK) != 0)
.right
else
null;
const sgr = terminal.modes.get(.mouse_format_sgr);
var buf: [32]u8 = undefined;
const n = input.encodeMouseMotion(held_btn, cell.col, cell.row, sgr, &buf);
if (n > 0) {
focused.sendInput(buf[0..n]) catch |err| {
log.warn("failed to send mouse motion: {}", .{err});
};
}
self.updateCursor(desired_cursor);
return true;
}
}
}

const pin = fullViewPinFromMouse(focused, view, mouse_x, mouse_y, host.window_w, host.window_h, self.font, host.term_cols, host.term_rows, host.ui_scale);

if (view.selection_dragging) {
Expand Down Expand Up @@ -574,6 +652,22 @@ pub const SessionInteractionComponent = struct {
};
};

fn terminalHasMouseTracking(terminal: anytype) bool {
return terminal.modes.get(.mouse_event_normal) or
terminal.modes.get(.mouse_event_button) or
terminal.modes.get(.mouse_event_any) or
terminal.modes.get(.mouse_event_x10);
}

fn sdlToMouseButton(sdl_button: u8) ?input.MouseButton {
return switch (sdl_button) {
c.SDL_BUTTON_LEFT => .left,
c.SDL_BUTTON_MIDDLE => .middle,
c.SDL_BUTTON_RIGHT => .right,
else => null,
};
}

const CellPosition = struct { col: u16, row: u16 };

fn fullViewCellFromMouse(
Expand Down