godot/scene/gui/box_container.cpp
Rémi Verschelde b5334d14f7
Update copyright statements to 2021
Happy new year to the wonderful Godot community!

2020 has been a tough year for most of us personally, but a good year for
Godot development nonetheless with a huge amount of work done towards Godot
4.0 and great improvements backported to the long-lived 3.2 branch.

We've had close to 400 contributors to engine code this year, authoring near
7,000 commit! (And that's only for the `master` branch and for the engine code,
there's a lot more when counting docs, demos and other first-party repos.)

Here's to a great year 2021 for all Godot users 🎆
2021-01-01 20:19:21 +01:00

363 lines
9.6 KiB
C++

/*************************************************************************/
/* box_container.cpp */
/*************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/*************************************************************************/
/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur. */
/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md). */
/* */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the */
/* "Software"), to deal in the Software without restriction, including */
/* without limitation the rights to use, copy, modify, merge, publish, */
/* distribute, sublicense, and/or sell copies of the Software, and to */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions: */
/* */
/* The above copyright notice and this permission notice shall be */
/* included in all copies or substantial portions of the Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
/*************************************************************************/
#include "box_container.h"
#include "label.h"
#include "margin_container.h"
struct _MinSizeCache {
int min_size;
bool will_stretch;
int final_size;
};
void BoxContainer::_resort() {
/** First pass, determine minimum size AND amount of stretchable elements */
Size2i new_size = get_size();
int sep = get_theme_constant("separation"); //,vertical?"VBoxContainer":"HBoxContainer");
bool rtl = is_layout_rtl();
bool first = true;
int children_count = 0;
int stretch_min = 0;
int stretch_avail = 0;
float stretch_ratio_total = 0;
Map<Control *, _MinSizeCache> min_size_cache;
for (int i = 0; i < get_child_count(); i++) {
Control *c = Object::cast_to<Control>(get_child(i));
if (!c || !c->is_visible_in_tree()) {
continue;
}
if (c->is_set_as_top_level()) {
continue;
}
Size2i size = c->get_combined_minimum_size();
_MinSizeCache msc;
if (vertical) { /* VERTICAL */
stretch_min += size.height;
msc.min_size = size.height;
msc.will_stretch = c->get_v_size_flags() & SIZE_EXPAND;
} else { /* HORIZONTAL */
stretch_min += size.width;
msc.min_size = size.width;
msc.will_stretch = c->get_h_size_flags() & SIZE_EXPAND;
}
if (msc.will_stretch) {
stretch_avail += msc.min_size;
stretch_ratio_total += c->get_stretch_ratio();
}
msc.final_size = msc.min_size;
min_size_cache[c] = msc;
children_count++;
}
if (children_count == 0) {
return;
}
int stretch_max = (vertical ? new_size.height : new_size.width) - (children_count - 1) * sep;
int stretch_diff = stretch_max - stretch_min;
if (stretch_diff < 0) {
//avoid negative stretch space
stretch_diff = 0;
}
stretch_avail += stretch_diff; //available stretch space.
/** Second, pass successively to discard elements that can't be stretched, this will run while stretchable
elements exist */
bool has_stretched = false;
while (stretch_ratio_total > 0) { // first of all, don't even be here if no stretchable objects exist
has_stretched = true;
bool refit_successful = true; //assume refit-test will go well
float error = 0; // Keep track of accumulated error in pixels
for (int i = 0; i < get_child_count(); i++) {
Control *c = Object::cast_to<Control>(get_child(i));
if (!c || !c->is_visible_in_tree()) {
continue;
}
if (c->is_set_as_top_level()) {
continue;
}
ERR_FAIL_COND(!min_size_cache.has(c));
_MinSizeCache &msc = min_size_cache[c];
if (msc.will_stretch) { //wants to stretch
//let's see if it can really stretch
float final_pixel_size = stretch_avail * c->get_stretch_ratio() / stretch_ratio_total;
// Add leftover fractional pixels to error accumulator
error += final_pixel_size - (int)final_pixel_size;
if (final_pixel_size < msc.min_size) {
//if available stretching area is too small for widget,
//then remove it from stretching area
msc.will_stretch = false;
stretch_ratio_total -= c->get_stretch_ratio();
refit_successful = false;
stretch_avail -= msc.min_size;
msc.final_size = msc.min_size;
break;
} else {
msc.final_size = final_pixel_size;
// Dump accumulated error if one pixel or more
if (error >= 1) {
msc.final_size += 1;
error -= 1;
}
}
}
}
if (refit_successful) { //uf refit went well, break
break;
}
}
/** Final pass, draw and stretch elements **/
int ofs = 0;
if (!has_stretched) {
if (!vertical) {
switch (align) {
case ALIGN_BEGIN:
if (rtl) {
ofs = stretch_diff;
}
break;
case ALIGN_CENTER:
ofs = stretch_diff / 2;
break;
case ALIGN_END:
if (!rtl) {
ofs = stretch_diff;
}
break;
}
} else {
switch (align) {
case ALIGN_BEGIN:
break;
case ALIGN_CENTER:
ofs = stretch_diff / 2;
break;
case ALIGN_END:
ofs = stretch_diff;
break;
}
}
}
first = true;
int idx = 0;
int start;
int end;
int delta;
if (!rtl || vertical) {
start = 0;
end = get_child_count();
delta = +1;
} else {
start = get_child_count() - 1;
end = -1;
delta = -1;
}
for (int i = start; i != end; i += delta) {
Control *c = Object::cast_to<Control>(get_child(i));
if (!c || !c->is_visible_in_tree()) {
continue;
}
if (c->is_set_as_top_level()) {
continue;
}
_MinSizeCache &msc = min_size_cache[c];
if (first) {
first = false;
} else {
ofs += sep;
}
int from = ofs;
int to = ofs + msc.final_size;
if (msc.will_stretch && idx == children_count - 1) {
//adjust so the last one always fits perfect
//compensating for numerical imprecision
to = vertical ? new_size.height : new_size.width;
}
int size = to - from;
Rect2 rect;
if (vertical) {
rect = Rect2(0, from, new_size.width, size);
} else {
rect = Rect2(from, 0, size, new_size.height);
}
fit_child_in_rect(c, rect);
ofs = to;
idx++;
}
}
Size2 BoxContainer::get_minimum_size() const {
/* Calculate MINIMUM SIZE */
Size2i minimum;
int sep = get_theme_constant("separation"); //,vertical?"VBoxContainer":"HBoxContainer");
bool first = true;
for (int i = 0; i < get_child_count(); i++) {
Control *c = Object::cast_to<Control>(get_child(i));
if (!c) {
continue;
}
if (c->is_set_as_top_level()) {
continue;
}
if (!c->is_visible()) {
continue;
}
Size2i size = c->get_combined_minimum_size();
if (vertical) { /* VERTICAL */
if (size.width > minimum.width) {
minimum.width = size.width;
}
minimum.height += size.height + (first ? 0 : sep);
} else { /* HORIZONTAL */
if (size.height > minimum.height) {
minimum.height = size.height;
}
minimum.width += size.width + (first ? 0 : sep);
}
first = false;
}
return minimum;
}
void BoxContainer::_notification(int p_what) {
switch (p_what) {
case NOTIFICATION_SORT_CHILDREN: {
_resort();
} break;
case NOTIFICATION_THEME_CHANGED: {
minimum_size_changed();
} break;
case NOTIFICATION_TRANSLATION_CHANGED:
case NOTIFICATION_LAYOUT_DIRECTION_CHANGED: {
queue_sort();
} break;
}
}
void BoxContainer::set_alignment(AlignMode p_align) {
align = p_align;
_resort();
}
BoxContainer::AlignMode BoxContainer::get_alignment() const {
return align;
}
void BoxContainer::add_spacer(bool p_begin) {
Control *c = memnew(Control);
c->set_mouse_filter(MOUSE_FILTER_PASS); //allow spacer to pass mouse events
if (vertical) {
c->set_v_size_flags(SIZE_EXPAND_FILL);
} else {
c->set_h_size_flags(SIZE_EXPAND_FILL);
}
add_child(c);
if (p_begin) {
move_child(c, 0);
}
}
BoxContainer::BoxContainer(bool p_vertical) {
vertical = p_vertical;
align = ALIGN_BEGIN;
}
void BoxContainer::_bind_methods() {
ClassDB::bind_method(D_METHOD("add_spacer", "begin"), &BoxContainer::add_spacer);
ClassDB::bind_method(D_METHOD("get_alignment"), &BoxContainer::get_alignment);
ClassDB::bind_method(D_METHOD("set_alignment", "alignment"), &BoxContainer::set_alignment);
BIND_ENUM_CONSTANT(ALIGN_BEGIN);
BIND_ENUM_CONSTANT(ALIGN_CENTER);
BIND_ENUM_CONSTANT(ALIGN_END);
ADD_PROPERTY(PropertyInfo(Variant::INT, "alignment", PROPERTY_HINT_ENUM, "Begin,Center,End"), "set_alignment", "get_alignment");
}
MarginContainer *VBoxContainer::add_margin_child(const String &p_label, Control *p_control, bool p_expand) {
Label *l = memnew(Label);
l->set_text(p_label);
add_child(l);
MarginContainer *mc = memnew(MarginContainer);
mc->add_theme_constant_override("margin_left", 0);
mc->add_child(p_control);
add_child(mc);
if (p_expand) {
mc->set_v_size_flags(SIZE_EXPAND_FILL);
}
return mc;
}