ladybird/Userland/Applications/PixelPaint/LayerListWidget.cpp
Marcus Nilsson dc9b18da22 PixelPaint: Implement automatic scrolling in LayerListWidget
The previous implementation of automatic scrolling in LayerListWidget
relied on mousemove events to perform the scrolling, which didn't
produce the expected behavior. Instead use the new auto scroll timer.
2021-09-16 22:29:21 +02:00

402 lines
12 KiB
C++

/*
* Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
* Copyright (c) 2021, Mustafa Quraish <mustafa@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include "LayerListWidget.h"
#include "Image.h"
#include "ImageEditor.h"
#include "Layer.h"
#include <LibGUI/Painter.h>
#include <LibGfx/Palette.h>
REGISTER_WIDGET(PixelPaint, LayerListWidget);
namespace PixelPaint {
LayerListWidget::LayerListWidget()
{
set_should_hide_unnecessary_scrollbars(false);
horizontal_scrollbar().set_visible(false);
}
LayerListWidget::~LayerListWidget()
{
if (m_image)
m_image->remove_client(*this);
}
size_t LayerListWidget::to_gadget_index(size_t layer_index) const
{
return m_image->layer_count() - layer_index - 1;
}
size_t LayerListWidget::to_layer_index(size_t gadget_index) const
{
return m_image->layer_count() - gadget_index - 1;
}
void LayerListWidget::set_image(Image* image)
{
if (m_image == image)
return;
if (m_image)
m_image->remove_client(*this);
m_image = image;
if (m_image)
m_image->add_client(*this);
rebuild_gadgets();
}
void LayerListWidget::rebuild_gadgets()
{
m_gadgets.clear();
if (m_image) {
for (int layer_index = m_image->layer_count() - 1; layer_index >= 0; --layer_index) {
m_gadgets.append({ static_cast<size_t>(layer_index), {}, false, {} });
}
}
relayout_gadgets();
}
void LayerListWidget::resize_event(GUI::ResizeEvent& event)
{
AbstractScrollableWidget::resize_event(event);
relayout_gadgets();
}
void LayerListWidget::get_gadget_rects(Gadget const& gadget, Gfx::IntRect& outer_rect, Gfx::IntRect& thumbnail_rect, Gfx::IntRect& text_rect)
{
outer_rect = gadget.rect;
outer_rect.translate_by(0, -vertical_scrollbar().value());
outer_rect.translate_by(frame_thickness(), frame_thickness());
if (gadget.is_moving) {
outer_rect.translate_by(0, gadget.movement_delta.y());
}
thumbnail_rect = { outer_rect.x(), outer_rect.y(), outer_rect.height(), outer_rect.height() };
thumbnail_rect.shrink(8, 8);
text_rect = { thumbnail_rect.right() + 10, outer_rect.y(), outer_rect.width(), outer_rect.height() };
text_rect.intersect(outer_rect);
}
void LayerListWidget::paint_event(GUI::PaintEvent& event)
{
GUI::Painter painter(*this);
painter.add_clip_rect(event.rect());
painter.fill_rect(event.rect(), palette().button());
if (!m_image)
return;
painter.fill_rect(event.rect(), palette().button());
auto paint_gadget = [&](auto& gadget) {
auto& layer = m_image->layer(gadget.layer_index);
Gfx::IntRect adjusted_rect;
Gfx::IntRect thumbnail_rect;
Gfx::IntRect text_rect;
get_gadget_rects(gadget, adjusted_rect, thumbnail_rect, text_rect);
if (gadget.is_moving) {
painter.fill_rect(adjusted_rect, palette().selection().lightened(1.5f));
} else if (layer.is_selected()) {
painter.fill_rect(adjusted_rect, palette().selection());
}
painter.draw_rect(adjusted_rect, palette().color(ColorRole::BaseText));
painter.draw_scaled_bitmap(thumbnail_rect, layer.bitmap(), layer.bitmap().rect());
if (layer.is_visible()) {
painter.draw_text(text_rect, layer.name(), Gfx::TextAlignment::CenterLeft, layer.is_selected() ? palette().selection_text() : palette().button_text());
painter.draw_rect(thumbnail_rect, palette().color(ColorRole::BaseText));
} else {
painter.draw_text(text_rect, layer.name(), Gfx::TextAlignment::CenterLeft, palette().color(ColorRole::DisabledText));
painter.draw_rect(thumbnail_rect, palette().color(ColorRole::DisabledText));
}
};
for (auto& gadget : m_gadgets) {
if (!gadget.is_moving)
paint_gadget(gadget);
}
if (m_moving_gadget_index.has_value())
paint_gadget(m_gadgets[m_moving_gadget_index.value()]);
Gfx::StylePainter::paint_frame(painter, rect(), palette(), Gfx::FrameShape::Box, Gfx::FrameShadow::Sunken, 2);
}
Optional<size_t> LayerListWidget::gadget_at(Gfx::IntPoint const& position)
{
for (size_t i = 0; i < m_gadgets.size(); ++i) {
if (m_gadgets[i].rect.contains(position))
return i;
}
return {};
}
void LayerListWidget::mousedown_event(GUI::MouseEvent& event)
{
if (!m_image)
return;
if (event.button() != GUI::MouseButton::Left)
return;
Gfx::IntPoint translated_event_point = { 0, vertical_scrollbar().value() + event.y() };
auto maybe_gadget_index = gadget_at(translated_event_point);
if (!maybe_gadget_index.has_value())
return;
auto gadget_index = maybe_gadget_index.value();
m_moving_gadget_index = gadget_index;
m_selected_gadget_index = gadget_index;
m_moving_event_origin = translated_event_point;
auto& gadget = m_gadgets[m_moving_gadget_index.value()];
auto& layer = m_image->layer(to_layer_index(gadget_index));
set_selected_layer(&layer);
gadget.is_moving = true;
gadget.movement_delta = {};
update();
}
void LayerListWidget::mousemove_event(GUI::MouseEvent& event)
{
if (!m_image)
return;
if (!m_moving_gadget_index.has_value())
return;
Gfx::IntPoint translated_event_point = { 0, vertical_scrollbar().value() + event.y() };
auto delta = translated_event_point - m_moving_event_origin;
if (delta.y() == 0)
return;
auto& gadget = m_gadgets[m_moving_gadget_index.value()];
VERIFY(gadget.is_moving);
gadget.movement_delta.set_y(delta.y());
auto inner_rect_max_height = widget_inner_rect().height() - 2 + vertical_scrollbar().max();
if (delta.y() < 0 && gadget.rect.y() < -delta.y())
gadget.movement_delta.set_y(-gadget.rect.y());
else if (delta.y() > 0 && gadget.rect.bottom() + delta.y() > inner_rect_max_height)
gadget.movement_delta.set_y(inner_rect_max_height - gadget.rect.bottom());
m_automatic_scroll_delta = automatic_scroll_delta_from_position(event.position());
set_automatic_scrolling_timer(vertical_scrollbar().is_scrollable() && !m_automatic_scroll_delta.is_null());
relayout_gadgets();
}
void LayerListWidget::mouseup_event(GUI::MouseEvent& event)
{
if (!m_image)
return;
if (event.button() != GUI::MouseButton::Left)
return;
if (!m_moving_gadget_index.has_value())
return;
size_t old_index = m_moving_gadget_index.value();
size_t new_index = hole_index_during_move();
if (new_index >= m_image->layer_count())
new_index = m_image->layer_count() - 1;
m_moving_gadget_index = {};
set_automatic_scrolling_timer(false);
auto old_layer_index = to_layer_index(old_index);
auto new_layer_index = to_layer_index(new_index);
m_image->change_layer_index(old_layer_index, new_layer_index);
}
void LayerListWidget::context_menu_event(GUI::ContextMenuEvent& event)
{
Gfx::IntPoint translated_event_point = { 0, vertical_scrollbar().value() + event.position().y() };
auto gadget_index = gadget_at(translated_event_point);
if (gadget_index.has_value()) {
m_selected_gadget_index = gadget_index.value();
auto& layer = m_image->layer(to_layer_index(m_selected_gadget_index));
set_selected_layer(&layer);
}
if (on_context_menu_request)
on_context_menu_request(event);
}
void LayerListWidget::on_automatic_scrolling_timer_fired()
{
auto& gadget = m_gadgets[m_moving_gadget_index.value()];
VERIFY(gadget.is_moving);
if (m_automatic_scroll_delta.y() == 0)
return;
if (vertical_scrollbar().is_min() && m_automatic_scroll_delta.y() < 0)
return;
if (vertical_scrollbar().is_max() && m_automatic_scroll_delta.y() > 0)
return;
vertical_scrollbar().set_value(vertical_scrollbar().value() + m_automatic_scroll_delta.y());
gadget.movement_delta.set_y(gadget.movement_delta.y() + m_automatic_scroll_delta.y());
auto inner_rect_max_height = widget_inner_rect().height() - 2 + vertical_scrollbar().max();
auto gadget_absolute_position = gadget.rect.y() + gadget.movement_delta.y();
if (gadget_absolute_position < 0)
gadget.movement_delta.set_y(-gadget.rect.y());
else if (gadget_absolute_position + gadget.rect.height() >= inner_rect_max_height)
gadget.movement_delta.set_y(inner_rect_max_height - gadget.rect.bottom());
else
relayout_gadgets();
}
void LayerListWidget::image_did_add_layer(size_t layer_index)
{
if (m_moving_gadget_index.has_value()) {
m_gadgets[m_moving_gadget_index.value()].is_moving = false;
m_moving_gadget_index = {};
}
auto gadget_index = to_gadget_index(layer_index);
Gadget gadget { gadget_index, {}, false, {} };
m_gadgets.insert(gadget_index, gadget);
relayout_gadgets();
}
void LayerListWidget::image_did_remove_layer(size_t layer_index)
{
if (m_moving_gadget_index.has_value()) {
m_gadgets[m_moving_gadget_index.value()].is_moving = false;
m_moving_gadget_index = {};
}
// No -1 here since a layer has already been removed.
auto gadget_index = m_image->layer_count() - layer_index;
m_gadgets.remove(gadget_index);
m_selected_gadget_index = to_gadget_index(0);
relayout_gadgets();
}
void LayerListWidget::image_did_modify_layer_properties(size_t layer_index)
{
update(m_gadgets[to_gadget_index(layer_index)].rect);
}
void LayerListWidget::image_did_modify_layer_bitmap(size_t layer_index)
{
Gfx::IntRect adjusted_rect;
Gfx::IntRect thumbnail_rect;
Gfx::IntRect text_rect;
get_gadget_rects(m_gadgets[to_gadget_index(layer_index)], adjusted_rect, thumbnail_rect, text_rect);
update(thumbnail_rect);
}
void LayerListWidget::image_did_modify_layer_stack()
{
rebuild_gadgets();
}
static constexpr int gadget_height = 40;
static constexpr int gadget_spacing = -1;
static constexpr int vertical_step = gadget_height + gadget_spacing;
size_t LayerListWidget::hole_index_during_move() const
{
VERIFY(is_moving_gadget());
auto& moving_gadget = m_gadgets[m_moving_gadget_index.value()];
int center_y_of_moving_gadget = moving_gadget.rect.translated(0, moving_gadget.movement_delta.y()).center().y();
return center_y_of_moving_gadget / vertical_step;
}
void LayerListWidget::select_bottom_layer()
{
if (!m_image || !m_image->layer_count())
return;
m_selected_gadget_index = to_gadget_index(0);
set_selected_layer(&m_image->layer(0));
}
void LayerListWidget::select_top_layer()
{
if (!m_image || !m_image->layer_count())
return;
m_selected_gadget_index = 0;
set_selected_layer(&m_image->layer(to_layer_index(0)));
}
void LayerListWidget::cycle_through_selection(int delta)
{
if (!m_image || !m_image->layer_count())
return;
auto current_index = static_cast<int>(m_selected_gadget_index);
current_index += delta;
if (current_index < 0)
current_index = m_gadgets.size() - 1;
if (current_index > static_cast<int>(m_gadgets.size()) - 1)
current_index = 0;
m_selected_gadget_index = current_index;
auto selected_layer_index = to_layer_index(m_selected_gadget_index);
set_selected_layer(&m_image->layer(selected_layer_index));
}
void LayerListWidget::relayout_gadgets()
{
int y = 0;
Optional<size_t> hole_index;
if (is_moving_gadget())
hole_index = hole_index_during_move();
size_t index = 0;
for (auto& gadget : m_gadgets) {
if (gadget.is_moving)
continue;
if (index == hole_index)
y += vertical_step;
gadget.rect = { 0, y, widget_inner_rect().width(), gadget_height };
y += vertical_step;
++index;
}
auto total_gadget_height = static_cast<int>(m_gadgets.size()) * vertical_step + 6;
set_content_size({ widget_inner_rect().width(), total_gadget_height });
vertical_scrollbar().set_range(0, max(total_gadget_height - height(), 0));
update();
}
void LayerListWidget::set_selected_layer(Layer* layer)
{
if (!m_image)
return;
if (layer->is_selected())
return;
for (size_t i = 0; i < m_image->layer_count(); ++i) {
if (layer == &m_image->layer(i)) {
m_image->layer(i).set_selected(true);
m_selected_gadget_index = to_gadget_index(i);
scroll_into_view(m_gadgets[m_selected_gadget_index].rect, false, true);
} else {
m_image->layer(i).set_selected(false);
}
}
if (on_layer_select)
on_layer_select(layer);
update();
}
}