// blend1.cpp : DLL アプリケーションのエントリ ポイントを定義します。
//

#include "stdafx.h"
#include <math.h>
#include <stdlib.h>



#ifdef _MANAGED
#pragma managed(push, off)
#endif



extern "C" {
typedef unsigned char n_byte;

int __stdcall get_blend_func_count();
char* __stdcall get_blend_func_key(int no);
char* __stdcall get_blend_func_name(int no);
void __stdcall blend(unsigned char* dst,const unsigned char* col,const unsigned char* alpha,int col_step
								 ,int alpha_step,int num_channel,int num_pixel,int no);



//追加する合成方法の数を返す。
int __stdcall get_blend_func_count()
{
    return 1;
}


//psdファイルに保存するときのkeyを返す。
/*
'norm' = normal
'dark' = darken
'lite' = lighten
'hue ' = hue
'sat ' = saturation
'colr' = color
'lum ' = luminosity
'mul ' = multiply
'scrn' = screen
'diss' = dissolve
'over' = overlay
'hLit' = hard light
'sLit' = soft light
'diff' = difference
'smud' = exlusion
'div ' = color dodge
'idiv' = color burn
*/
char* __stdcall get_blend_func_key(int no) 
{
	if (no == 0) {
		return "sand";
	}
	return 0;
}

//合成方法の名前を返す。
char* __stdcall get_blend_func_name(int no)
{
	if (no == 0) {
		return "砂トーン";
	}
	return "";
}


//合成を行う関数。
//num_channel チャンネル数。グレーモードの場合は１、カラーモードの場合は３

void __stdcall blend(unsigned char* dst,const unsigned char* col,const unsigned char* alpha,int col_step,int alpha_step
					,int num_channel,int num_pixel,int no)
{
	if (no == 0) {//ディザ拡散
		if (num_channel == 1) {
			const unsigned char* col_end = col + num_pixel * col_step;
			while (col < col_end) {
				unsigned int a1 = *alpha;
				if (a1 != 0){//α値の完全に透明部分は描かない

				int sand_rand = rand() % 101;
				int kido = (77 * *col + 150 * *col + 29 * *col) / 256;//輝度計算
				double deep = (int)(100 - kido / 2.55) * (*alpha/255.0) ;

				if (sand_rand <= deep && deep != 0){
				*dst = 0 ;
				}		else {
				*dst = (unsigned char)*dst;
				}
				}

				alpha += alpha_step;
				col += col_step;
				dst += col_step;
			}
		}
		else if (num_channel == 3) {
			const unsigned char* col_end = col + num_pixel * col_step;

//			srand(0); // rand関数を初期化する。0を入れてるのは適当
			while (col < col_end) {
				unsigned int a1 = *alpha;
				if (a1 != 0){//α値の完全に透明部分は描かない

				int sand_rand = rand() % 101 ;
				int kido = (77 * *(col + 2) + 150 * *(col + 1) + 29 * *col) / 256;//輝度計算
				double deep = (int)(100 - kido / 2.55) * (*alpha/255.0) ;

				if (sand_rand <= deep && deep != 0){
				*dst = 0 ;
				*(dst + 1) = 0 ;
				*(dst + 2) = 0 ;
				}		else {
				*dst = (unsigned char)*dst;
				*(dst + 1) = (unsigned char)*(dst + 1) ;
				*(dst + 2) = (unsigned char)*(dst + 2) ;
				}
				}
				alpha += alpha_step;
				col += col_step;
				dst += col_step;
			}
		}
	}

}

//下のレイヤーと結合で使用される
void __stdcall merge(n_byte* dst,const n_byte* col,const n_byte* base_col,const n_byte* alpha,const n_byte* base_alpha
					 ,int col_step,int alpha_step,int base_alpha_step,int num_channel,int num_pixel,int no)
{
	if (no == 0) {
		if (num_channel == 1) {
			const unsigned char* col_end = col + num_pixel * col_step;
			while (col < col_end) {
				unsigned int a0 = *base_alpha;
				unsigned int a1 = *alpha;

				if (a1 != 0){
					int sand_rand = rand() % 101 ;
					int kido = (77 * *col + 150 * *col + 29 * *col) / 256;//輝度計算
					double deep = (int)(100 - kido / 2.55) * (a1/255.0) ;

				if (sand_rand <= deep && deep != 0){
				*dst = 0 ;
				*(dst + 1) = 255 ;
				}		else {
				*dst = (unsigned char)*base_col;
				*(dst + 1) = *base_alpha;
				}
				}
				else {
					*dst = *base_col;
					*(dst + 1) = *base_alpha;
				}

				dst += 2;
				col += col_step;
				base_col += col_step;
				alpha += alpha_step;
				base_alpha += alpha_step;
			}
		}
		else if (num_channel == 3) {
			const unsigned char* col_end = col + num_pixel * col_step;
			while (col < col_end) {
				unsigned int a0 = *base_alpha;
				unsigned int a1 = *alpha;

				if (a1 != 0){
					int sand_rand = rand() % 101 ;
					int kido = (77 * *(col + 2) + 150 * *(col + 1) + 29 * *col) / 256;//輝度計算	
					double deep = (int)(100 - kido / 2.55) * (a1/255.0) ;

				if (sand_rand <= deep && deep != 0){
				*dst = 0 ;
				*(dst + 1) = 0 ;
				*(dst + 2) = 0 ;
				*(dst + 3) = 255;	
				}		else {
				*dst = (unsigned char)*base_col;
				*(dst + 1) = (unsigned char)*(base_col + 1) ;
				*(dst + 2) = (unsigned char)*(base_col + 2) ;
				*(dst + 3) = *base_alpha;
				}
		
				}
				else {//現在のレイヤーが透明ならば
					*dst = *base_col;
					*(dst + 1) = *(base_col + 1);
					*(dst + 2) = *(base_col + 2);
					*(dst + 3) = *base_alpha;
				}

				dst += 4;
				col += col_step;
				base_col += col_step;
				alpha += alpha_step;
				base_alpha += base_alpha_step;
			}
		}
	}
}



}
BOOL APIENTRY DllMain( HMODULE hModule,
                       DWORD  ul_reason_for_call,
                       LPVOID lpReserved
					 )
{
    return TRUE;
}

#ifdef _MANAGED
#pragma managed(pop)
#endif