Hi would it be possible to convert some DirectX code to XNA C#? float Noise(int x) { x = (x<<13) ^ x; return (1.0 - ((x * (x*x * 15731 + 789221) + 1376312589) & 0x7fffffff) / 1073741824.0); } float CosInterpolate(float v1, float v2, float a) { float angle = a * D3DX_PI; float prc = (1.0f - cos(angle)) * 0.5f; return v1*(1.0f - prc) + v2*prc; } HRESULT HEIGHTMAP::CreateRandomHeightMap(int seed, float noiseSize, float persistence, int octaves) { //For each map node for(int y=0;y<m_size.y;y++) for(int x=0;x<m_size.x;x++) { //Scale x & y to the range of 0.0 - m_size float xf = ((float)x / (float)m_size.x) * noiseSize; float yf = ((float)y / (float)m_size.y) * noiseSize; float total = 0; // For each octave for(int i=0;i<octaves;i++) { //Calculate frequency and amplitude (different for each octave) float freq = pow(2, i); float amp = pow(persistence, i); //Calculate the x,y noise coordinates float tx = xf * freq; float ty = yf * freq; int tx_int = tx; int ty_int = ty; //Calculate the fractions of x & y float fracX = tx - tx_int; float fracY = ty - ty_int; //Get the noise of this octave for each of these 4 points float v1 = Noise(tx_int + ty_int * 57 + seed); float v2 = Noise(tx_int+ 1 + ty_int * 57 + seed); float v3 = Noise(tx_int + (ty_int+1) * 57 + seed); float v4 = Noise(tx_int + 1 + (ty_int+1) * 57 + seed); //Smooth in the X-axis float i1 = CosInterpolate(v1 , v2 , fracX); float i2 = CosInterpolate(v3 , v4 , fracX); //Smooth in the Y-axis total += CosInterpolate(i1 , i2 , fracY) * amp; } int b = 128 + total * 128.0f; if(b < 0)b = 0; if(b > 255)b = 255; //Save to heightMap m_pHeightMap[x + y * m_size.x] = (b / 255.0f) * m_maxHeight; } return S_OK; } thanks

This isn't really DirectX specific code apart from the pi constant and to a lesser extent the hresult enumeration.
I haven't tested it, but replacing them with a C# equivalent (Math.PI and functions in the Math namespace, your own defined return type) should probably make most of it working in XNA.