ブラー.txt

#include "DxLib.h"

struct BlurScreen
{
	int screen[2];
	int current;
	int alpha;
	int screenWidth, screenHeight;
	int offsetX1, offsetX2, offsetY1, offsetY2;
};

void InitBlurScreen(BlurScreen *blur, int alpha,
	int offsetX1, int offsetY1, int offsetX2, int offsetY2)
{
	if (!blur) return;

	int depth;
	GetScreenState(&blur->screenWidth, &blur->screenHeight, &depth);
	for (int n = 0; n<2; ++n)
		blur->screen[n] = MakeScreen(blur->screenWidth, blur->screenHeight);
	blur->current = 0;
	blur->alpha = alpha;
	blur->offsetX1 = offsetX1;
	blur->offsetX2 = offsetX2;
	blur->offsetY1 = offsetY1;
	blur->offsetY2 = offsetY2;
}

void DestroyBlurScreen(BlurScreen *blur)
{
	if (!blur) return;
	for (int n = 0; n<2; ++n)
		DeleteGraph(blur->screen[n]);
}

void PreRenderBlurScreen(BlurScreen *blur)
{
	if (!blur) return;

	SetDrawScreen(blur->screen[blur->current]);
	ClearDrawScreen();
}

void PostRenderBlurScreen(BlurScreen *blur)
{
	if (!blur) return;

	int drawMode = GetDrawMode();
	SetDrawMode(DX_DRAWMODE_BILINEAR);

	int brendMode, blendParam;
	GetDrawBlendMode(&brendMode, &blendParam);
	SetDrawBlendMode(DX_BLENDMODE_ALPHA, blur->alpha);

	DrawExtendGraph(
		blur->offsetX1, blur->offsetY1,
		blur->screenWidth + blur->offsetX2,
		blur->screenHeight + blur->offsetY2,
		blur->screen[1 - blur->current], FALSE);
	SetDrawBlendMode(brendMode, blendParam);
	SetDrawMode(drawMode);

	SetDrawScreen(DX_SCREEN_BACK);
	DrawGraph(0, 0, blur->screen[blur->current], FALSE);
	blur->current = 1 - blur->current;
}

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)
{
	ChangeWindowMode(TRUE);
	if (DxLib_Init() == -1) return 0;
	SetDrawScreen(DX_SCREEN_BACK);

	BlurScreen blur;
	InitBlurScreen(&blur, 240, -2, -2, 2, 2);

	while (!ProcessMessage())
	{
		PreRenderBlurScreen(&blur);
		DrawBox(100, 100, 200, 200, GetColor(255, 180, 255), TRUE);
		DrawBox(270, 190, 370, 290, GetColor(255, 255, 255), TRUE);
		DrawBox(440, 280, 540, 380, GetColor(255, 255, 180), TRUE);
		PostRenderBlurScreen(&blur);
		ScreenFlip();
	}

	DestroyBlurScreen(&blur);
	DxLib_End();
	return 0;
}