godot/tools/editor/io_plugins/editor_atlas.cpp

160 lines
4.6 KiB
C++

/*************************************************************************/
/* editor_atlas.cpp */
/*************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* http://www.godotengine.org */
/*************************************************************************/
/* Copyright (c) 2007-2017 Juan Linietsky, Ariel Manzur. */
/* */
/* 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 "editor_atlas.h"
#include "print_string.h"
struct _EditorAtlasWorkRect {
Size2i s;
Point2i p;
int idx;
_FORCE_INLINE_ bool operator<(const _EditorAtlasWorkRect& p_r) const { return s.width > p_r.s.width; };
};
struct _EditorAtlasWorkRectResult {
Vector<_EditorAtlasWorkRect> result;
int max_w;
int max_h;
};
void EditorAtlas::fit(const Vector<Size2i>& p_rects,Vector<Point2i>& r_result, Size2i& r_size) {
//super simple, almost brute force scanline stacking fitter
//it's pretty basic for now, but it tries to make sure that the aspect ratio of the
//resulting atlas is somehow square. This is necesary because video cards have limits
//on texture size (usually 2048 or 4096), so the more square a texture, the more chances
//it will work in every hardware.
// for example, it will prioritize a 1024x1024 atlas (works everywhere) instead of a
// 256x8192 atlas (won't work anywhere).
ERR_FAIL_COND(p_rects.size()==0);
Vector<_EditorAtlasWorkRect> wrects;
wrects.resize(p_rects.size());
for(int i=0;i<p_rects.size();i++) {
wrects[i].s=p_rects[i];
wrects[i].idx=i;
}
wrects.sort();
int widest = wrects[0].s.width;
Vector<_EditorAtlasWorkRectResult> results;
for(int i=0;i<=12;i++) {
int w = 1<<i;
int max_h=0;
int max_w=0;
if ( w < widest )
continue;
Vector<int> hmax;
hmax.resize(w);
for(int j=0;j<w;j++)
hmax[j]=0;
//place them
int ofs=0;
for(int j=0;j<wrects.size();j++) {
if (ofs+wrects[j].s.width > w) {
ofs=0;
}
int from_y=0;
for(int k=0;k<wrects[j].s.width;k++) {
if (hmax[ofs+k] > from_y)
from_y=hmax[ofs+k];
}
wrects[j].p.x=ofs;
wrects[j].p.y=from_y;
int end_h = from_y+wrects[j].s.height;
int end_w = ofs+wrects[j].s.width;
for(int k=0;k<wrects[j].s.width;k++) {
hmax[ofs+k]=end_h;
}
if (end_h > max_h)
max_h=end_h;
if (end_w > max_w)
max_w=end_w;
ofs+=wrects[j].s.width;
}
_EditorAtlasWorkRectResult result;
result.result=wrects;
result.max_h=max_h;
result.max_w=max_w;
results.push_back(result);
}
//find the result with the best aspect ratio
int best=-1;
float best_aspect=1e20;
for(int i=0;i<results.size();i++) {
float h = results[i].max_h;
float w = results[i].max_w;
float aspect = h>w ? h/w : w/h;
if (aspect < best_aspect) {
best=i;
best_aspect=aspect;
}
}
r_result.resize(p_rects.size());
for(int i=0;i<p_rects.size();i++) {
r_result[ results[best].result[i].idx ]=results[best].result[i].p;
}
r_size=Size2(results[best].max_w,results[best].max_h );
}