ladybird/Userland/Libraries/LibGUI/OpacitySlider.cpp
2021-10-27 22:05:58 +03:00

146 lines
4.8 KiB
C++

/*
* Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibGUI/OpacitySlider.h>
#include <LibGUI/Painter.h>
#include <LibGfx/Palette.h>
#include <LibGfx/StylePainter.h>
REGISTER_WIDGET(GUI, OpacitySlider)
namespace GUI {
OpacitySlider::OpacitySlider(Gfx::Orientation orientation)
: AbstractSlider(orientation)
{
// FIXME: Implement vertical mode.
VERIFY(orientation == Gfx::Orientation::Horizontal);
set_min(0);
set_max(100);
set_value(100);
set_fixed_height(20);
}
OpacitySlider::~OpacitySlider()
{
}
Gfx::IntRect OpacitySlider::frame_inner_rect() const
{
return rect().shrunken(4, 4);
}
void OpacitySlider::paint_event(PaintEvent& event)
{
GUI::Painter painter(*this);
painter.add_clip_rect(event.rect());
auto inner_rect = frame_inner_rect();
// Grid pattern
Gfx::StylePainter::paint_transparency_grid(painter, inner_rect, palette());
// Alpha gradient
for (int x = inner_rect.left(); x <= inner_rect.right(); ++x) {
float relative_offset = (float)x / (float)width();
float alpha = relative_offset * 255.0f;
Color color { 0, 0, 0, (u8)alpha };
painter.fill_rect({ x, inner_rect.y(), 1, inner_rect.height() }, color);
}
constexpr int notch_size = 3;
int notch_y_top = inner_rect.top() + notch_size;
int notch_y_bottom = inner_rect.bottom() - notch_size;
int notch_x = inner_rect.left() + ((float)value() / (float)max() * (float)inner_rect.width());
// Top notch
painter.set_pixel(notch_x, notch_y_top, palette().threed_shadow2());
for (int i = notch_size; i >= 0; --i) {
painter.set_pixel(notch_x - (i + 1), notch_y_top - i - 1, palette().threed_highlight());
for (int j = 0; j < i * 2; ++j) {
painter.set_pixel(notch_x - (i + 1) + j + 1, notch_y_top - i - 1, palette().button());
}
painter.set_pixel(notch_x + (i + 0), notch_y_top - i - 1, palette().threed_shadow1());
painter.set_pixel(notch_x + (i + 1), notch_y_top - i - 1, palette().threed_shadow2());
}
// Bottom notch
painter.set_pixel(notch_x, notch_y_bottom, palette().threed_shadow2());
for (int i = 0; i < notch_size; ++i) {
painter.set_pixel(notch_x - (i + 1), notch_y_bottom + i + 1, palette().threed_highlight());
for (int j = 0; j < i * 2; ++j) {
painter.set_pixel(notch_x - (i + 1) + j + 1, notch_y_bottom + i + 1, palette().button());
}
painter.set_pixel(notch_x + (i + 0), notch_y_bottom + i + 1, palette().threed_shadow1());
painter.set_pixel(notch_x + (i + 1), notch_y_bottom + i + 1, palette().threed_shadow2());
}
// Hairline
// NOTE: If we're in the whiter part of the gradient, the notch is painted as shadow between the notches.
// If we're in the darker part, the notch is painted as highlight.
// We adjust the hairline's x position so it lines up with the shadow/highlight of the notches.
u8 h = ((float)value() / (float)max()) * 255.0f;
if (h < 128)
painter.draw_line({ notch_x, notch_y_top }, { notch_x, notch_y_bottom }, Color(h, h, h, 255));
else
painter.draw_line({ notch_x - 1, notch_y_top }, { notch_x - 1, notch_y_bottom }, Color(h, h, h, 255));
// Text label
auto percent_text = String::formatted("{}%", (int)((float)value() / (float)max() * 100.0f));
painter.draw_text(inner_rect.translated(1, 1), percent_text, Gfx::TextAlignment::Center, Color::Black);
painter.draw_text(inner_rect, percent_text, Gfx::TextAlignment::Center, Color::White);
// Frame
Gfx::StylePainter::paint_frame(painter, rect(), palette(), Gfx::FrameShape::Container, Gfx::FrameShadow::Sunken, 2);
}
int OpacitySlider::value_at(const Gfx::IntPoint& position) const
{
auto inner_rect = frame_inner_rect();
if (position.x() < inner_rect.left())
return min();
if (position.x() > inner_rect.right())
return max();
float relative_offset = (float)(position.x() - inner_rect.x()) / (float)inner_rect.width();
return relative_offset * (float)max();
}
void OpacitySlider::mousedown_event(MouseEvent& event)
{
if (event.button() == MouseButton::Primary) {
m_dragging = true;
set_value(value_at(event.position()));
return;
}
AbstractSlider::mousedown_event(event);
}
void OpacitySlider::mousemove_event(MouseEvent& event)
{
if (m_dragging) {
set_value(value_at(event.position()));
return;
}
AbstractSlider::mousemove_event(event);
}
void OpacitySlider::mouseup_event(MouseEvent& event)
{
if (event.button() == MouseButton::Primary) {
m_dragging = false;
return;
}
AbstractSlider::mouseup_event(event);
}
void OpacitySlider::mousewheel_event(MouseEvent& event)
{
set_value(value() - event.wheel_delta());
}
}