ladybird/Userland/Applications/PixelPaint/BucketTool.cpp
Mustafa Quraish 3bf204fd03 PixelPaint: Fix BucketTool out of memory crashes
The BFS implementation for BucketTool's flood-fill had sitations
which could result in infinite loop, causing OOM crashes due to
the queue growing unbounded. The way to fix this is to keep track
of the pixels we have already visited in the flood-fill algorithm
and ignore those if we ever encounter them again.

This also fixes the crashing issue from #9003. We still need a
better way to account for transparency, but that is beyond the scope
of this commit, and this issue still exists without any transparent
pixels.
2021-09-09 11:27:48 +02:00

123 lines
3.6 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include "BucketTool.h"
#include "ImageEditor.h"
#include "Layer.h"
#include <AK/HashTable.h>
#include <AK/Queue.h>
#include <LibGUI/BoxLayout.h>
#include <LibGUI/Label.h>
#include <LibGUI/Painter.h>
#include <LibGUI/ValueSlider.h>
#include <LibGfx/Bitmap.h>
#include <LibGfx/Rect.h>
namespace PixelPaint {
BucketTool::BucketTool()
{
}
BucketTool::~BucketTool()
{
}
static float color_distance_squared(Gfx::Color const& lhs, Gfx::Color const& rhs)
{
int a = rhs.red() - lhs.red();
int b = rhs.green() - lhs.green();
int c = rhs.blue() - lhs.blue();
return (a * a + b * b + c * c) / (255.0f * 255.0f);
}
static void flood_fill(Gfx::Bitmap& bitmap, Gfx::IntPoint const& start_position, Color target_color, Color fill_color, int threshold)
{
VERIFY(bitmap.bpp() == 32);
if (target_color == fill_color)
return;
if (!bitmap.rect().contains(start_position))
return;
float threshold_normalized_squared = (threshold / 100.0f) * (threshold / 100.0f);
Queue<Gfx::IntPoint> queue;
queue.enqueue(start_position);
HashTable<Gfx::IntPoint> visited;
while (!queue.is_empty()) {
auto position = queue.dequeue();
if (visited.contains(position))
continue;
visited.set(position);
auto pixel_color = bitmap.get_pixel<Gfx::StorageFormat::BGRA8888>(position.x(), position.y());
if (color_distance_squared(pixel_color, target_color) > threshold_normalized_squared)
continue;
bitmap.set_pixel<Gfx::StorageFormat::BGRA8888>(position.x(), position.y(), fill_color);
if (position.x() != 0)
queue.enqueue(position.translated(-1, 0));
if (position.x() != bitmap.width() - 1)
queue.enqueue(position.translated(1, 0));
if (position.y() != 0)
queue.enqueue(position.translated(0, -1));
if (position.y() != bitmap.height() - 1)
queue.enqueue(position.translated(0, 1));
}
}
void BucketTool::on_mousedown(Layer* layer, MouseEvent& event)
{
if (!layer)
return;
auto& layer_event = event.layer_event();
if (!layer->rect().contains(layer_event.position()))
return;
GUI::Painter painter(layer->bitmap());
auto target_color = layer->bitmap().get_pixel(layer_event.x(), layer_event.y());
flood_fill(layer->bitmap(), layer_event.position(), target_color, m_editor->color_for(layer_event), m_threshold);
layer->did_modify_bitmap();
m_editor->did_complete_action();
}
GUI::Widget* BucketTool::get_properties_widget()
{
if (!m_properties_widget) {
m_properties_widget = GUI::Widget::construct();
m_properties_widget->set_layout<GUI::VerticalBoxLayout>();
auto& threshold_container = m_properties_widget->add<GUI::Widget>();
threshold_container.set_fixed_height(20);
threshold_container.set_layout<GUI::HorizontalBoxLayout>();
auto& threshold_label = threshold_container.add<GUI::Label>("Threshold:");
threshold_label.set_text_alignment(Gfx::TextAlignment::CenterLeft);
threshold_label.set_fixed_size(80, 20);
auto& threshold_slider = threshold_container.add<GUI::ValueSlider>(Orientation::Horizontal, "%");
threshold_slider.set_range(0, 100);
threshold_slider.set_value(m_threshold);
threshold_slider.on_change = [&](int value) {
m_threshold = value;
};
set_primary_slider(&threshold_slider);
}
return m_properties_widget.ptr();
}
}