/// <summary>
/// Creates an asteroid
/// </summary>
/// <param name="size">Size of the asteroid</param>
/// <param name="verts">Vertices defining the shape of the asteroid</param>
/// <param name="indices">Indices defining the shape of the asteroid</param>
/// <param name="pos">Initial position of the asteroid</param>
/// <param name="rot">Initial rotation of the asteroid (in radians)</param>
/// <param name="dir">Initial direction of the asteroid</param>
/// <param name="linSpeed">Linear speed of the asteroid</param>
/// <param name="scale">Scale to apply to the vertices</param>
public Asteroid(AsteroidSize size, Shape s,
Vector2 pos, float rot, Vector2 dir, float linSpeed, float scale)
: base(s, rot, dir, scale)
{
Position = pos;
Size = size;
LinSpeed = linSpeed;
}
public override bool Intersects(Shape s)
{
foreach (Triangle t in Triangles)
{
if (t.Intersects(s)) return true;
}
return false;
}
public void Draw(Shape s)
{
effect.World = s.World;
foreach (EffectPass pass in effect.CurrentTechnique.Passes)
{
pass.Apply();
gDevice.DrawUserIndexedPrimitives<VertexPositionColor>(PrimitiveType.LineList,
s.Vertices, 0, s.Vertices.Length, s.Indices, 0, s.Indices.Length / 2);
}
}
/// <summary>
/// Constructs the base of an entity
/// </summary>
/// <param name="body">Shape defining the body of the entity</param>
/// <param name="rot">The initial rotation of the entity</param>
/// <param name="dir">Initial direction of the entity</param>
/// <param name="scale">Scale of the entity</param>
public Entity(Shape body, float rot, Vector2 dir, float scale)
{
Body = body;
Position = Body.Position;
Rotation = rot;
LinSpeed = 0f;
Scale = scale;
Direction = dir;
EffectiveHeight = 15f;
EffectiveWidth = 15f;
}
/// <summary>
/// Constructs the base of an entity
/// </summary>
/// <param name="body">Shape defining the body of the entity</param>
/// <param name="rot">The initial rotation of the entity</param>
protected Entity(Shape body, float rot)
{
Body = body;
Position = Body.Position;
Rotation = rot;
LinSpeed = 0f;
Scale = 1f;
// Find the initial direction, based on the rotation
Direction = new Vector2((float)Math.Cos(rot), (float)Math.Sin(rot));
// Initial values
EffectiveHeight = 15f;
EffectiveWidth = 15f;
}
public virtual bool Intersects(Shape s)
{
if (s is ConcaveShape)
return (s as ConcaveShape).Intersects(this);
if (s == this)
return true;
int i = 0;
// Using this shape...
for (i = 0; i < this.TransformedVertices.Length; i++)
{
// The next index should be i + 1
// However, if we're on the last cycle, we have looped around.
// The next index is the one we started with (0)
int nextIndex = i + 1;
if (i == this.TransformedVertices.Length - 1)
nextIndex = 0;
Vector2 side = this.TransformedVertices[nextIndex] - this.TransformedVertices[i];
// Find the axis perpendicular to the current side.
// This is what we'll use to test the separation.
Vector2 axis = new Vector2(side.Y, -side.X);
Projection p1 = this.Project(axis);
Projection p2 = s.Project(axis);
if (!p1.Overlaps(p2))
return false;
}
// Next shape...
for (i = 0; i < s.TransformedVertices.Length; i++)
{
// The next index should be i + 1
// However, if we're on the last cycle, we have looped around.
// The next index is the one we started with (0)
int nextIndex = i + 1;
if (i == s.TransformedVertices.Length - 1)
nextIndex = 0;
Vector2 side = s.TransformedVertices[nextIndex] - s.TransformedVertices[i];
// Find the axis perpendicular to the current side.
// This is what we'll use to test the separation.
Vector2 axis = new Vector2(side.Y, -side.X);
Projection p1 = this.Project(axis);
Projection p2 = s.Project(axis);
if (!p1.Overlaps(p2))
return false;
}
return true;
}