//
//   パレットによる半透明処理
//
//    1998/ 8/22  宍戸　輝光
//

#include <windows.h>
#include <stdlib.h>

LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM);

LPBYTE lpBuf,lpBMP,bgBMP,bufBMP,partBMP;
LPBITMAPINFO bufDIB;
LPRGBQUAD lpRGB;
int x,y,p;

int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,
                    PSTR szCmdLine, int iCmdShow){

	HWND hwnd;
	MSG  msg;
	WNDCLASSEX  wndclass ;

	int i,j,k;

	wndclass.cbSize        = sizeof(wndclass);
	wndclass.style         = CS_HREDRAW | CS_VREDRAW;
	wndclass.lpfnWndProc   = WndProc;
	wndclass.cbClsExtra    = 0;
	wndclass.cbWndExtra    = 0;
	wndclass.hInstance     = hInstance;
	wndclass.hIcon         = LoadIcon (NULL, IDI_APPLICATION);
	wndclass.hCursor       = LoadCursor (NULL, IDC_ARROW);
	wndclass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
	wndclass.lpszMenuName  = NULL;
	wndclass.lpszClassName = "Test Window";
	wndclass.hIconSm       = LoadIcon (NULL, IDI_APPLICATION);

	RegisterClassEx (&wndclass);

	hwnd = CreateWindow ("Test Window",
		    "半透明処理",           
                    WS_OVERLAPPEDWINDOW,
                    32,32,
                    288,288,
                    NULL,
                    NULL,
                    hInstance,
		            NULL);

	lpBMP=GlobalAlloc(GPTR,256*256+32*32); // 背景・キャラクタ用メモリ

	bgBMP=lpBMP; // 背景とキャラクタにビットマップメモリを分配
	partBMP=lpBMP+256*256;

	lpBuf=GlobalAlloc // 表示用バッファに必要なメモリをまとめて確保
		(GPTR,sizeof(BITMAPINFO)+255*sizeof(RGBQUAD)+256*256);

	bufDIB=(LPBITMAPINFO)lpBuf; // メモリを分配
	lpRGB=(RGBQUAD*)(lpBuf+sizeof(BITMAPINFOHEADER));
	bufBMP=(BYTE*)(lpBuf+sizeof(BITMAPINFOHEADER)+256*sizeof(RGBQUAD));

	bufDIB->bmiHeader.biSize=sizeof(BITMAPINFOHEADER); // BITMAPINFO構造体
	bufDIB->bmiHeader.biWidth=256;
	bufDIB->bmiHeader.biHeight=256;
	bufDIB->bmiHeader.biPlanes=1;
	bufDIB->bmiHeader.biBitCount=8;
	bufDIB->bmiHeader.biCompression=BI_RGB;
	bufDIB->bmiHeader.biSizeImage=0;
	bufDIB->bmiHeader.biXPelsPerMeter=0;
	bufDIB->bmiHeader.biYPelsPerMeter=0;
	bufDIB->bmiHeader.biClrUsed=0;
	bufDIB->bmiHeader.biClrImportant=0;

	bufDIB->bmiColors[0]=lpRGB[0]; // カラーテーブルの先頭

	lpRGB[0].rgbRed=0; // 背景の色設定
	lpRGB[0].rgbGreen=0;
	lpRGB[0].rgbBlue=0;

	lpRGB[1].rgbRed=255;
	lpRGB[1].rgbGreen=0;
	lpRGB[1].rgbBlue=0;

	lpRGB[2].rgbRed=0;
	lpRGB[2].rgbGreen=255;
	lpRGB[2].rgbBlue=0;

	lpRGB[3].rgbRed=0;
	lpRGB[3].rgbGreen=0;
	lpRGB[3].rgbBlue=255;

	lpRGB[4].rgbRed=255;
	lpRGB[4].rgbGreen=255;
	lpRGB[4].rgbBlue=0;

	lpRGB[5].rgbRed=255;
	lpRGB[5].rgbGreen=0;
	lpRGB[5].rgbBlue=255;

	lpRGB[6].rgbRed=0;
	lpRGB[6].rgbGreen=255;
	lpRGB[6].rgbBlue=255;

	lpRGB[7].rgbRed=255;
	lpRGB[7].rgbGreen=255;
	lpRGB[7].rgbBlue=255;

	lpRGB[8].rgbRed=64; // キャラクタ本来の色を設定
	lpRGB[8].rgbGreen=128;
	lpRGB[8].rgbBlue=255;

	lpRGB[16].rgbRed=255;
	lpRGB[16].rgbGreen=128;
	lpRGB[16].rgbBlue=64;

	lpRGB[24].rgbRed=255;
	lpRGB[24].rgbGreen=255;
	lpRGB[24].rgbBlue=255;

	for (i=1;i<8;i++) { // 半透明の色を設定
	
		lpRGB[8+i].rgbRed=(lpRGB[8].rgbRed*2+lpRGB[i].rgbRed)/3;
		lpRGB[8+i].rgbGreen=(lpRGB[8].rgbGreen*2+lpRGB[i].rgbGreen)/3;
		lpRGB[8+i].rgbBlue=(lpRGB[8].rgbBlue*2+lpRGB[i].rgbBlue)/3;

		lpRGB[16+i].rgbRed=(lpRGB[16].rgbRed*2+lpRGB[i].rgbRed)/3;
		lpRGB[16+i].rgbGreen=(lpRGB[16].rgbGreen*2+lpRGB[i].rgbGreen)/3;
		lpRGB[16+i].rgbBlue=(lpRGB[16].rgbBlue*2+lpRGB[i].rgbBlue)/3;

		lpRGB[24+i].rgbRed=(lpRGB[24].rgbRed*2+lpRGB[i].rgbRed)/3;
		lpRGB[24+i].rgbGreen=(lpRGB[24].rgbGreen*2+lpRGB[i].rgbGreen)/3;
		lpRGB[24+i].rgbBlue=(lpRGB[24].rgbBlue*2+lpRGB[i].rgbBlue)/3;

	}

	for (i=0;i<8;i++) // 背景ビットマップを作成
		for (j=0;j<8;j++) {

			p=rand() % 8;

			for (k=0;k<32;k++) 
				FillMemory(bgBMP+(i*32+k)*256+j*32,32,p);
	
		}

    for (i=0;i<32;i++) // キャラクタを抜き色でクリア
		for (j=0;j<32;j++)
			partBMP[j+i*32]=255;

		for (i=0;i<16;i++) { // キャラクタ作成

		FillMemory(partBMP+i*32,32,8);

	}

	for (i=0;i<12;i++)
		FillMemory(partBMP+(32-i)*32+(16-i),i*2,16);

	for (i=16;i<21;i++)
		FillMemory(partBMP+i*32+15,2,24);

	x=112;
	y=112;

	ShowWindow (hwnd,iCmdShow);      // ウインドウを表示
	UpdateWindow (hwnd);             // 再描画

	while (GetMessage (&msg,NULL,0,0)) { // メッセージ処理

		TranslateMessage(&msg);
		DispatchMessage(&msg);

	}

	return msg.wParam ;

}

LRESULT CALLBACK WndProc (HWND hwnd, UINT iMsg, WPARAM wParam, LPARAM lParam) {

	HDC hdc;
	PAINTSTRUCT ps;
	int i,j;

	switch (iMsg) {

		case WM_DESTROY :
			GlobalFree(lpBuf); // バッファを解放
			GlobalFree(lpBMP); // バッファを解放
			PostQuitMessage(0);
			return 0;

		case WM_PAINT:

			hdc=BeginPaint(hwnd,&ps);

			CopyMemory(bufBMP,bgBMP,256*256);

			for (i=0;i<32;i++) // キャラクタを半透明で描画
				for (j=0;j<32;j++)
					if (partBMP[j+i*32]!=255)
						bufBMP[x+j+(y+i)*256]+=partBMP[j+i*32];
			
			StretchDIBits(hdc,0,0,256,256,0,0,256,256,bufBMP,bufDIB,
				DIB_RGB_COLORS,SRCCOPY);

			EndPaint(hwnd,&ps);

			return 0;

		case WM_KEYDOWN: // カーソルキーでキャラクタ移動

			if (wParam==VK_UP && y<224)
				y=y+2;

			if (wParam==VK_RIGHT && x<224)
				x=x+2;

			if (wParam==VK_DOWN && y>0)
				y=y-2;

			if (wParam==VK_LEFT && x>0)
				x=x-2;

			InvalidateRgn(hwnd,NULL,FALSE);
			UpdateWindow (hwnd); // 再描画

			return 0;

	}

	return DefWindowProc (hwnd, iMsg, wParam, lParam) ;

}