summaryrefslogtreecommitdiff
path: root/Userland/Applications/PixelPaint/Tools/BrushTool.cpp
blob: 62e2075d2343c71d8a06485eebf727bc4e11b5a7 (plain)
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
/*
 * Copyright (c) 2020, Ben Jilks <benjyjilks@gmail.com>
 * Copyright (c) 2021, Mustafa Quraish <mustafa@serenityos.org>
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#include "BrushTool.h"
#include "../ImageEditor.h"
#include "../Layer.h"
#include <LibGUI/Action.h>
#include <LibGUI/BoxLayout.h>
#include <LibGUI/Label.h>
#include <LibGUI/Painter.h>
#include <LibGUI/ValueSlider.h>
#include <LibGfx/Color.h>
#include <LibGfx/Rect.h>

namespace PixelPaint {

BrushTool::BrushTool()
{
}

BrushTool::~BrushTool()
{
}

void BrushTool::on_mousedown(Layer* layer, MouseEvent& event)
{
    if (!layer)
        return;

    auto& layer_event = event.layer_event();
    if (layer_event.button() != GUI::MouseButton::Primary && layer_event.button() != GUI::MouseButton::Secondary)
        return;

    // Shift+Click draws a line from the last position to current one.
    if (layer_event.shift() && m_has_clicked) {
        draw_line(layer->bitmap(), color_for(layer_event), m_last_position, layer_event.position());
        auto modified_rect = Gfx::IntRect::from_two_points(m_last_position, layer_event.position()).inflated(m_size * 2, m_size * 2);
        layer->did_modify_bitmap(modified_rect);
        m_last_position = layer_event.position();
        return;
    }

    const int first_draw_opacity = 10;

    for (int i = 0; i < first_draw_opacity; ++i)
        draw_point(layer->bitmap(), color_for(layer_event), layer_event.position());

    layer->did_modify_bitmap(Gfx::IntRect::centered_on(layer_event.position(), Gfx::IntSize { m_size * 2, m_size * 2 }));
    m_last_position = layer_event.position();
    m_has_clicked = true;
}

void BrushTool::on_mousemove(Layer* layer, MouseEvent& event)
{
    if (!layer)
        return;

    auto& layer_event = event.layer_event();
    if (!(layer_event.buttons() & GUI::MouseButton::Primary || layer_event.buttons() & GUI::MouseButton::Secondary))
        return;

    draw_line(layer->bitmap(), color_for(layer_event), m_last_position, layer_event.position());

    auto modified_rect = Gfx::IntRect::from_two_points(m_last_position, layer_event.position()).inflated(m_size * 2, m_size * 2);

    layer->did_modify_bitmap(modified_rect);
    m_last_position = layer_event.position();
    m_was_drawing = true;
}

void BrushTool::on_mouseup(Layer*, MouseEvent&)
{
    if (m_was_drawing) {
        m_editor->did_complete_action();
        m_was_drawing = false;
    }
}

Color BrushTool::color_for(GUI::MouseEvent const& event)
{
    return m_editor->color_for(event);
}

void BrushTool::draw_point(Gfx::Bitmap& bitmap, Gfx::Color const& color, Gfx::IntPoint const& point)
{
    for (int y = point.y() - size(); y < point.y() + size(); y++) {
        for (int x = point.x() - size(); x < point.x() + size(); x++) {
            auto distance = point.distance_from({ x, y });
            if (x < 0 || x >= bitmap.width() || y < 0 || y >= bitmap.height())
                continue;
            if (distance >= size())
                continue;

            auto falloff = get_falloff(distance);
            auto pixel_color = color;
            pixel_color.set_alpha(falloff * 255);
            bitmap.set_pixel(x, y, bitmap.get_pixel(x, y).blend(pixel_color));
        }
    }
}

void BrushTool::draw_line(Gfx::Bitmap& bitmap, Gfx::Color const& color, Gfx::IntPoint const& start, Gfx::IntPoint const& end)
{
    int length_x = end.x() - start.x();
    int length_y = end.y() - start.y();
    float y_step = length_y == 0 ? 0 : (float)(length_y) / (float)(length_x);
    if (y_step > abs(length_y))
        y_step = abs(length_y);
    if (y_step < -abs(length_y))
        y_step = -abs(length_y);
    if (y_step == 0 && start.x() == end.x())
        return;

    int start_x = start.x();
    int end_x = end.x();
    int start_y = start.y();
    int end_y = end.y();
    if (start_x > end_x) {
        swap(start_x, end_x);
        swap(start_y, end_y);
    }

    float y = start_y;
    for (int x = start_x; x <= end_x; x++) {
        int start_step_y = y;
        int end_step_y = y + y_step;
        if (start_step_y > end_step_y)
            swap(start_step_y, end_step_y);
        for (int i = start_step_y; i <= end_step_y; i++)
            draw_point(bitmap, color, { x, i });
        y += y_step;
    }
}

GUI::Widget* BrushTool::get_properties_widget()
{
    if (!m_properties_widget) {
        m_properties_widget = GUI::Widget::construct();
        m_properties_widget->set_layout<GUI::VerticalBoxLayout>();

        auto& size_container = m_properties_widget->add<GUI::Widget>();
        size_container.set_fixed_height(20);
        size_container.set_layout<GUI::HorizontalBoxLayout>();

        auto& size_label = size_container.add<GUI::Label>("Size:");
        size_label.set_text_alignment(Gfx::TextAlignment::CenterLeft);
        size_label.set_fixed_size(80, 20);

        auto& size_slider = size_container.add<GUI::ValueSlider>(Orientation::Horizontal, "px");
        size_slider.set_range(1, 100);
        size_slider.set_value(m_size);

        size_slider.on_change = [&](int value) {
            set_size(value);
        };
        set_primary_slider(&size_slider);

        auto& hardness_container = m_properties_widget->add<GUI::Widget>();
        hardness_container.set_fixed_height(20);
        hardness_container.set_layout<GUI::HorizontalBoxLayout>();

        auto& hardness_label = hardness_container.add<GUI::Label>("Hardness:");
        hardness_label.set_text_alignment(Gfx::TextAlignment::CenterLeft);
        hardness_label.set_fixed_size(80, 20);

        auto& hardness_slider = hardness_container.add<GUI::ValueSlider>(Orientation::Horizontal, "%");
        hardness_slider.set_range(1, 100);
        hardness_slider.set_value(m_hardness);

        hardness_slider.on_change = [&](int value) {
            set_hardness(value);
        };
        set_secondary_slider(&hardness_slider);
    }

    return m_properties_widget.ptr();
}

}