private void GenerateTunnels(Vector2 start, float maxLength = 2000.0f, float turnStrength = 0.2f)
{
//1234
//12345
//498764867
//582764
var random = new FastRandom(498764867);
const float step = 2.0f;
var terrainHeight = _terrain.TerrainSize.Y / 2.0f;
var maxSize = new Vector2(30.0f);
var currentPosition = start;
var currentDirection = Vector2.UnitX;
var length = 0.0f;
while (length < maxLength)
{
var currentSize = maxSize + new Vector2(Math.Max(0.0f, length + 200.0f - maxLength)) * 1.0f;
var brushSize = new Vector2(random.NextFloat() * currentSize.X, random.NextFloat() * currentSize.Y);
var brush = new CircleBrush(
(brushSize.X + brushSize.Y) / 4.0f,
currentPosition + new Vector2(random.NextRangedFloat(), random.NextRangedFloat()));
_terrain.SetQuads(brush, false, true);
// Add rotation.
var rotationDir = random.NextRangedFloat();
// Prevent going outside terrain or going back.
if (currentPosition.Y > terrainHeight - 200.0f ||
(currentDirection.X < 0.0f && currentDirection.Y > 0.0f))
{
rotationDir = (rotationDir - 1.0f) * 0.1f;
}
else if (currentPosition.Y < -(terrainHeight + 200.0f) ||
(currentDirection.X < 0.0f && currentDirection.Y < 0.0f))
{
rotationDir = (rotationDir + 1.0f) * 0.1f;
}
// Apply rotation.
var rotation = rotationDir * turnStrength;
currentDirection = new Vector2(
currentDirection.X * MathCore.Cos(rotation) + -currentDirection.Y * MathCore.Sin(rotation),
currentDirection.Y * MathCore.Cos(rotation) + currentDirection.X * MathCore.Sin(rotation));
currentPosition += currentDirection * step;
length += step;
}
_terrain.Refresh();
}
private void Initialize(ICamera camera)
{
// Retrieve the necessary data.
var vector3 = camera.SceneNode.Position;
var cameraPosition = new Vector2(vector3.X, vector3.Y);
var halfScreenSize = camera.ScreenSize / 2.0f;
_lastCameraPosition = cameraPosition;
// Use the viewport's and screen's height to determine our particle size since it's contstant.
// Particle size = 2 pixels.
_particleSize = camera.ScreenSize.Y / (float)camera.Viewport.Height * 2.0f;
_halfParticleSize = _particleSize / 2.0f;
// Initialize the particles.
for (int i = 0; i < _particles.Length; ++i)
{
var particle = new Particle
{
Position = new Vector2(
cameraPosition.X + halfScreenSize.X * _random.NextRangedFloat(),
cameraPosition.Y + halfScreenSize.Y * _random.NextRangedFloat()),
Color = new Color(
1.0f - _random.NextFloat() * 0.2f,
1.0f - _random.NextFloat() * 0.2f,
1.0f - _random.NextFloat() * 0.2f,
1.0f - _random.NextFloat() * 0.2f)
};
_particles[i] = particle;
RebuildPartice(i, ref particle);
}
_hasInitialized = true;
}