Sample()

uint16_t Heightmap::Sample	(	float	x,
		float	y,
		bool	interpolated
	)		const

Definition at line 55 of file Heightmap.cpp.

{
    auto lerp = [](float a, float b, double t) { return a + (b - a) * t; };
    auto clamp = [](float x, float min, float max) { 
        return x > max ? max : (x < min) ? min : x;
    };
 
    clamp(x, 0, 1);
    clamp(y, 0, 1);
 
    if (!interpolated)
        return Get(x * (m_Width - 1), y * (m_Height - 1));
 
    float x1 = std::floor(x * (m_Width - 1));
    float y1 = std::floor(y * (m_Height - 1));
    float x2 = x1 + 1;
    float y2 = y1 + 1;
 
    float xp = x * m_Width - x1;
    float yp = y * m_Height - y1;
 
    float h11 = Get(x1, y1);
    float h21 = Get(x2, y1);
    float h12 = Get(x1, y2);
    float h22 = Get(x2, y2);
 
    auto v1 = lerp(h11, h21, xp);
    auto v2 = lerp(h12, h22, xp);
    auto h = lerp(v1, v2, yp);
    if (h < 0)
        h = 0;
    return (uint16_t) h;
 
}