public ITexture ConcentricSinusoidalRgba(uint textureWidth, uint textureHeight, int numQuarterWaves, bool taperInner, bool taperOuter, SineWavePoint centreWaveStartPoint = SineWavePoint.ZeroAscending, float maxAmplitude = 1)
{
var data = ConcentricSinusoidal(textureWidth, textureHeight, numQuarterWaves, taperInner, taperOuter, centreWaveStartPoint, maxAmplitude);
var pixelcount = textureWidth * textureHeight;
var rgba = new Rgba32[pixelcount];
for (var p = 0; p < pixelcount; p++)
{
var value = data[p];
rgba[p] = new Rgba32(
value > 0.0f ? value : 0.0f,
value < 0.0f ? -value : 0.0f,
0.0f, 0.2f //Alpha 1 so we can review it in normal draw pipeline
);
}
return(_gpuSurfaceManager.CreateRgbaTextureFromPixelData(textureWidth, textureHeight, rgba, SamplerType.Anisotropic, true, false));
}
private float[] ConcentricSinusoidal(uint textureWidth, uint textureHeight, int numHalfWaves, bool taperInner, bool taperOuter, SineWavePoint centreWaveStartPoint, float maxAmplitude)
{
var data = new float[textureWidth * textureHeight];
var hw = 0.5f * textureWidth;
var hh = 0.5f * textureHeight;
for (var y = 0; y < textureHeight; y++)
{
for (var x = 0; x < textureWidth; x++)
{
//Calculate linear array index for 2d pixel position
var index = (y * textureWidth) + x;
//Tranform absolute pixel coordinate on texture to
//-0.5 to +0.5 normalised range across texture dimensions
var fx = (x - hw) / textureWidth;
var fy = (y - hh) / textureHeight;
var distance = (float)Math.Sqrt((fx * fx) + (fy * fy));
if (distance > 0.5f)
{
//Bounds of wave "circles" max at width 1.0, cordners up to sqrt(2) zero
data[index] = 0.0f;
}
else
{
var linearFactor = distance / 0.5f; //Scales to 0 -> 1
var amp = maxAmplitude;
if (taperInner && linearFactor <= 0.5f)
{
amp *= linearFactor / 0.5f;
}
if (taperOuter && linearFactor > 0.5f)
{
amp *= 1.0f - ((linearFactor - 0.5f) / 0.5f);
}
float initAngleRads = 0.0f;
switch (centreWaveStartPoint)
{
case SineWavePoint.HalfPiMaxDescending:
initAngleRads = 0.5f * (float)Math.PI;
break;
case SineWavePoint.PiZeroDescending:
initAngleRads = (float)Math.PI;
break;
case SineWavePoint.OneHalfPiMaxAscending:
initAngleRads = 1.5f * (float)Math.PI;
break;
}
var totalAngleOverOscillations = 0.5f * (float)Math.PI * numHalfWaves;
var rads = initAngleRads + (linearFactor * totalAngleOverOscillations);
var value = (float)Math.Sin(rads) * amp;
data[index] = value;
}
}
}
return(data);
}
public ITexture ConcentricSinusoidalFloat32(uint textureWidth, uint textureHeight, int numQuarterWaves, bool taperInner, bool taperOuter, SineWavePoint centreWaveStartPoint = SineWavePoint.ZeroAscending, float maxAmplitude = 1)
{
var data = ConcentricSinusoidal(textureWidth, textureHeight, numQuarterWaves, taperInner, taperOuter, centreWaveStartPoint, maxAmplitude);
return(_gpuSurfaceManager.CreateFloat32TextureFromPixelData(textureWidth, textureHeight, data, SamplerType.Anisotropic));
}
