godot/scene/resources/bit_mask.cpp

/*************************************************************************/
/*  bit_mask.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 "bit_mask.h"
#include "io/image_loader.h"

void BitMap::create(const Size2& p_size) {

	ERR_FAIL_COND(p_size.width<1);
	ERR_FAIL_COND(p_size.height<1);

	width=p_size.width;
	height=p_size.height;
	bitmask.resize(((width*height)/8)+1);
	zeromem(bitmask.ptr(),bitmask.size());

}

void BitMap::create_from_image_alpha(const Image& p_image){

	ERR_FAIL_COND(p_image.empty());
	Image img=p_image;
	img.convert(Image::FORMAT_LA8);
	ERR_FAIL_COND(img.get_format()!=Image::FORMAT_LA8);

	create(Size2(img.get_width(),img.get_height()));


	DVector<uint8_t>::Read r = img.get_data().read();
	uint8_t *w = bitmask.ptr();

	for(int i=0;i<width*height;i++) {

		int bbyte = i/8;
		int bbit = i % 8;
		if (r[i*2])
			w[bbyte]|=(1<<bbit);
	}

}


void BitMap::set_bit_rect(const Rect2& p_rect,bool p_value) {

	Rect2i current = Rect2i(0,0,width,height).clip(p_rect);
	uint8_t *data = bitmask.ptr();

	for(int i=current.pos.x;i<current.pos.x+current.size.x;i++) {

		for(int j=current.pos.y;j<current.pos.y+current.size.y;j++) {


			int ofs = width * j + i;
			int bbyte = ofs/8;
			int bbit = ofs % 8;

			uint8_t b = data[bbyte];

			if (p_value)
				b|=(1<<bbit);
			else
				b&=!(1<<bbit);

			data[bbyte]=b;

		}
	}

}

int BitMap::get_true_bit_count() const {

	int ds = bitmask.size();
	const uint8_t *d = bitmask.ptr();
	int c=0;

//fast, almot branchless version

	for(int i=0;i<ds;i++) {

		c+=(d[i]&(1<<7))>>7;
		c+=(d[i]&(1<<6))>>6;
		c+=(d[i]&(1<<5))>>5;
		c+=(d[i]&(1<<4))>>4;
		c+=(d[i]&(1<<3))>>3;
		c+=(d[i]&(1<<2))>>2;
		c+=d[i]&1;
	}

	return c;
}


void BitMap::set_bit(const Point2& p_pos,bool p_value){

	int x=Math::fast_ftoi(p_pos.x);
	int y=Math::fast_ftoi(p_pos.y);

	ERR_FAIL_INDEX(x,width);
	ERR_FAIL_INDEX(y,height);

	int ofs = width * y + x;
	int bbyte = ofs/8;
	int bbit = ofs % 8;

	uint8_t b = bitmask[bbyte];

	if (p_value)
		b|=(1<<bbit);
	else
		b&=!(1<<bbit);

	bitmask[bbyte]=b;
}

bool BitMap::get_bit(const Point2& p_pos) const{

	int x=Math::fast_ftoi(p_pos.x);
	int y=Math::fast_ftoi(p_pos.y);
	ERR_FAIL_INDEX_V(x,width,false);
	ERR_FAIL_INDEX_V(y,height,false);

	int ofs = width * y + x;
	int bbyte = ofs/8;
	int bbit = ofs % 8;

	return (bitmask[bbyte]&(1<<bbit))!=0;

}

Size2 BitMap::get_size() const {

	return Size2(width,height);
}

void BitMap::_set_data(const Dictionary& p_d) {

	ERR_FAIL_COND(!p_d.has("size"));
	ERR_FAIL_COND(!p_d.has("data"));

	create(p_d["size"]);
	bitmask=p_d["data"];
}

Dictionary BitMap::_get_data() const{

	Dictionary d;
	d["size"]=get_size();
	d["data"]=bitmask;
	return d;
}

void BitMap::_bind_methods() {

	ClassDB::bind_method(_MD("create","size"),&BitMap::create);
	ClassDB::bind_method(_MD("create_from_image_alpha","image"),&BitMap::create_from_image_alpha);

	ClassDB::bind_method(_MD("set_bit","pos","bit"),&BitMap::set_bit);
	ClassDB::bind_method(_MD("get_bit","pos"),&BitMap::get_bit);

	ClassDB::bind_method(_MD("set_bit_rect","p_rect","bit"),&BitMap::set_bit_rect);
	ClassDB::bind_method(_MD("get_true_bit_count"),&BitMap::get_true_bit_count);

	ClassDB::bind_method(_MD("get_size"),&BitMap::get_size);

	ClassDB::bind_method(_MD("_set_data"),&BitMap::_set_data);
	ClassDB::bind_method(_MD("_get_data"),&BitMap::_get_data);

	ADD_PROPERTY(PropertyInfo(Variant::DICTIONARY,"data",PROPERTY_HINT_NONE,"",PROPERTY_USAGE_NOEDITOR),_SCS("_set_data"),_SCS("_get_data"));

}

BitMap::BitMap() {

	width=0;
	height=0;
}

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