#include <Siv3D.hpp>

struct ParamScale
{
	float scale;
	float unused[3];
};

void setScale(const int scale)
{
	ConstantBuffer<ParamScale> cb;
	cb->scale = scale;
	PostEffect::SetConstant(ShaderStage::Pixel, 1, cb);
}

void Main()
{
	Window::Resize(640, 480);

	Graphics::SetBackground(Palette::Black);

	int scale = 2;

	PostEffect::Register(PixelShader(L"scale.hlsl"));
	setScale(scale);

	const Texture texture(L"Example/Siv3D-kun.png");

	while (System::Update())
	{
		if (Input::KeyUp.clicked)
		{
			scale = Min(scale + 1, 4);
			setScale(scale);
		}
		else if (Input::KeyDown.clicked)
		{
			scale = Max(scale - 1, 1);
			setScale(scale);
		}

		texture.draw();

		PutText(L"scale = ", scale).from(2, 2);
	}
}