1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
|
/*
* Copyright (c) 2022, Mustafa Quraish <mustafa@serenityos.org>
* Copyright (c) 2022, Jelle Raaijmakers <jelle@gmta.nl>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include "AbstractZoomPanWidget.h"
namespace GUI {
constexpr float wheel_zoom_factor = 8.0f;
void AbstractZoomPanWidget::set_scale(float new_scale)
{
if (m_original_rect.is_null())
return;
m_scale = clamp(new_scale, m_min_scale, m_max_scale);
m_content_rect.set_size({
m_original_rect.width() * m_scale,
m_original_rect.height() * m_scale,
});
if (on_scale_change)
on_scale_change(m_scale);
relayout();
}
void AbstractZoomPanWidget::scale_by(float delta)
{
float new_scale = m_scale * AK::exp2(delta);
set_scale(new_scale);
}
void AbstractZoomPanWidget::scale_centered(float new_scale, Gfx::IntPoint const& center)
{
if (m_original_rect.is_null())
return;
new_scale = clamp(new_scale, m_min_scale, m_max_scale);
if (new_scale == m_scale)
return;
Gfx::FloatPoint focus_point {
center.x() - width() / 2.0f,
center.y() - height() / 2.0f,
};
m_origin = (m_origin + focus_point) * (new_scale / m_scale) - focus_point;
set_scale(new_scale);
}
void AbstractZoomPanWidget::start_panning(Gfx::IntPoint const& position)
{
m_saved_cursor = override_cursor();
set_override_cursor(Gfx::StandardCursor::Drag);
m_pan_start = m_origin;
m_pan_mouse_pos = position;
m_is_panning = true;
}
void AbstractZoomPanWidget::stop_panning()
{
m_is_panning = false;
set_override_cursor(m_saved_cursor);
}
void AbstractZoomPanWidget::pan_to(Gfx::IntPoint const& position)
{
// NOTE: `position` here (and `m_pan_mouse_pos`) are both in frame coordinates, not
// content coordinates, by design. The derived class should not have to keep track of
// the (zoomed) content coordinates itself, but just pass along the mouse position.
auto delta = position - m_pan_mouse_pos;
m_origin = m_pan_start.translated(-delta.x(), -delta.y());
relayout();
}
Gfx::FloatPoint AbstractZoomPanWidget::frame_to_content_position(Gfx::IntPoint const& frame_position) const
{
return {
(static_cast<float>(frame_position.x()) - m_content_rect.x()) / m_scale,
(static_cast<float>(frame_position.y()) - m_content_rect.y()) / m_scale,
};
}
Gfx::FloatRect AbstractZoomPanWidget::frame_to_content_rect(Gfx::IntRect const& frame_rect) const
{
Gfx::FloatRect content_rect;
content_rect.set_location(frame_to_content_position(frame_rect.location()));
content_rect.set_size({
frame_rect.width() / m_scale,
frame_rect.height() / m_scale,
});
return content_rect;
}
Gfx::FloatPoint AbstractZoomPanWidget::content_to_frame_position(Gfx::IntPoint const& content_position) const
{
return {
m_content_rect.x() + content_position.x() * m_scale,
m_content_rect.y() + content_position.y() * m_scale,
};
}
Gfx::FloatRect AbstractZoomPanWidget::content_to_frame_rect(Gfx::IntRect const& content_rect) const
{
Gfx::FloatRect frame_rect;
frame_rect.set_location(content_to_frame_position(content_rect.location()));
frame_rect.set_size({
content_rect.width() * m_scale,
content_rect.height() * m_scale,
});
return frame_rect;
}
void AbstractZoomPanWidget::mousewheel_event(GUI::MouseEvent& event)
{
float new_scale = scale() / AK::exp2(event.wheel_delta_y() / wheel_zoom_factor);
scale_centered(new_scale, event.position());
}
void AbstractZoomPanWidget::mousedown_event(GUI::MouseEvent& event)
{
if (!m_is_panning && event.button() == GUI::MouseButton::Middle) {
start_panning(event.position());
event.accept();
return;
}
}
void AbstractZoomPanWidget::resize_event(GUI::ResizeEvent& event)
{
relayout();
GUI::Widget::resize_event(event);
}
void AbstractZoomPanWidget::mousemove_event(GUI::MouseEvent& event)
{
if (!m_is_panning)
return;
pan_to(event.position());
event.accept();
}
void AbstractZoomPanWidget::mouseup_event(GUI::MouseEvent& event)
{
if (m_is_panning && event.button() == GUI::MouseButton::Middle) {
stop_panning();
event.accept();
return;
}
}
void AbstractZoomPanWidget::relayout()
{
if (m_original_rect.is_null())
return;
m_content_rect.set_location({
(width() / 2) - (m_content_rect.width() / 2) - m_origin.x(),
(height() / 2) - (m_content_rect.height() / 2) - m_origin.y(),
});
handle_relayout(m_content_rect);
}
void AbstractZoomPanWidget::reset_view()
{
m_origin = { 0, 0 };
set_scale(1.0f);
}
void AbstractZoomPanWidget::set_content_rect(Gfx::IntRect const& content_rect)
{
m_content_rect = enclosing_int_rect(content_to_frame_rect(content_rect));
update();
}
void AbstractZoomPanWidget::set_scale_bounds(float min_scale, float max_scale)
{
m_min_scale = min_scale;
m_max_scale = max_scale;
}
void AbstractZoomPanWidget::fit_content_to_rect(Gfx::IntRect const& viewport_rect, FitType type)
{
float const border_ratio = 0.95f;
auto image_size = m_original_rect.size();
auto height_ratio = floorf(border_ratio * viewport_rect.height()) / image_size.height();
auto width_ratio = floorf(border_ratio * viewport_rect.width()) / image_size.width();
float new_scale = 1.0f;
switch (type) {
case FitType::Width:
new_scale = width_ratio;
break;
case FitType::Height:
new_scale = height_ratio;
break;
case FitType::Both:
new_scale = min(height_ratio, width_ratio);
break;
}
auto const& offset = rect().center() - viewport_rect.center();
set_origin({ offset.x(), offset.y() });
set_scale(new_scale);
}
}
|
