// check for any collisions with snake (returns zero if no collision)
public int Collided(PictureBox collider)
{
// if the picturebox is null, obviously no collision
if (collider == null)
{
return(0);
}
// final result
int final = 0;
if (snakeHead.picBox.Bounds.IntersectsWith(collider.Bounds)) // check for head collision first
{
final |= HEAD_COLLISION; // shift the bits into the final result for head collision
}
// check for self collision
// loop through entire snake body to check for collisions
for (int i = 0; i < bodySegments.Count; i++) // start at 1 to skip the head
{
// retrieve current body part
BodySegment bdPart = bodySegments[i];
if (bdPart.Bounds.IntersectsWith(collider.Bounds)) // check for collision
{
final |= BODY_COLLISION; // shift the bits for body collision
break; // end the loop as no need to check other parts
}
// check for self collisions as well (head and body)
/*if (bdPart.Bounds.IntersectsWith(snakeHead.picBox.Bounds))
* {
* final |= SELF_COLLISION; // shift bits for head collision
* }*/
}
return(final);
}
void addLength(int size) // add a length to the snake in pixels
{
BodySegment trailing = bodySegments[bodySegments.Count - 1]; // retrieve the last body segment since we're building off the tail of the snake
// get the buildup angle
double buildAngle = trailing.velocity.Degrees * Math.PI / 180 + Math.PI; // flip it around
// get the change in each dimension
int dx = (int)(size * Math.Cos(buildAngle));
int dy = (int)(size * Math.Sin(buildAngle));
// add the new dimensions
trailing.grow(dx, dy);
}
// temporary constructor
public ContinuousSnake(int x, int y, CoreForm _mainForm, Vector _velocity, double size, bool red = false)
{
// assign all variables
this.Size = (int)size;
this.mainForm = _mainForm;
this.red = red;
// find angle to build the body in rads
double angle = _velocity.Degrees * Math.PI / 180 + Math.PI; // add PI radians to flip the angle around
// since the build must occur in opposite direction of velocity
int[] coords = new int[] { x, y }; // coords in proper form to be used
BodySegment segment = new BodySegment(0, 0, coords, _velocity.Clone(), mainForm); // set size to zero for now
int dx = (int)(BodyPart.SIZE * size * Math.Cos(angle)); // get change in each direction for the new size
int dy = (int)(BodyPart.SIZE * size * Math.Sin(angle)); // add negative because coords are reversed on screen
// whichever is zero will be default width
if (dx == 0)
{
dx = BodyPart.SIZE;
}
else
{
dy = BodyPart.SIZE;
}
segment.grow(dx, dy);
if (_velocity.Degrees == 180 || _velocity.Degrees == 90) // make the snake head at proper coords
{
snakeHead = new BodyPart(segment.X, segment.Y, _velocity.Clone(), mainForm);
}
else if (_velocity.Degrees == 0)
{
snakeHead = new BodyPart((int)(segment.X + BodyPart.SIZE * size - BodyPart.SIZE), segment.Y, _velocity.Clone(), mainForm);
}
else if (_velocity.Degrees == 0)
{
snakeHead = new BodyPart(segment.X, (int)(segment.Y + BodyPart.SIZE * size - BodyPart.SIZE), _velocity.Clone(), mainForm);
}
FixHead(); // fix head orientation based on velocity
// add the segment to the bodySegments list to keep track of it
bodySegments.Add(segment);
// set the timer event for preventing too fast player responses
interval.Elapsed += new ElapsedEventHandler(intervalFunc);
// do the red colour thing
if (red)
{
// make the segment red if the red flag is set
bodySegments[0].picBox.BackColor = Color.Red;
bodySegments[0].picBox.Image = null;
}
}
// check for self-collision
public bool SelfCollision()
{
for (int i = 2; i < bodySegments.Count; i++) // start at the third body part (index 2) since thats the only
// logical self-collision
{
// retrieve the target body part
BodySegment target = bodySegments[i];
// will be tested with head (also only logical means of collision)
if (snakeHead.picBox.Bounds.IntersectsWith(target.Bounds))
{
// return true as no need to test any longer
return(true);
}
}
// if the function reached this point, no collision occurred
return(false);
}
void clipPrev()
{
// get the previous item (second item)
BodySegment previous = bodySegments[1];
double removeAngle = previous.velocity.Degrees * Math.PI / 180 + Math.PI; // angle to remove material (add pi to flip around)
// amount to shrink in each dimension
int dx = (int)((BodyPart.SIZE - overlap) * Math.Cos(removeAngle));
int dy = (int)((BodyPart.SIZE - overlap) * Math.Sin(removeAngle));
previous.shrink(dx, dy); // shrink it
// clip the collider for this segment to the proper size
// amount to shrink in each dimension
dx = (int)((BodyPart.SIZE) * Math.Cos(removeAngle));
dy = (int)((BodyPart.SIZE) * Math.Sin(removeAngle));
previous.shrinkBounds(dx, dy); // shrink it
}
// check for any collisions with a gameobject
public int Collided(GameObject gameObject)
{
// final result
int final = 0;
if (gameObject.Collided(snakeHead.picBox)) // check for head collision first
{
final |= HEAD_COLLISION; // shift the bits into the final result for head collision
}
// loop through entire snake body to check for collisions
for (int i = 1; i < bodySegments.Count; i++) // start at 1 to skip the head
{
// retrieve current body part
BodySegment bdPart = bodySegments[i];
if (gameObject.Collided(bdPart.picBox)) // check for collision
{
final |= BODY_COLLISION; // shift the bits for body collision
break; // end the loop as no need to check other parts
}
}
return(final);
}
void turn(double degrees) // turn in a certain direction
{
// dont turn if dead or timer from last time is still ticking
if (!Alive && !interval.Enabled)
{
return;
}
// dont turn if the front-most body segment length is not equal or greater than two times the standard
// body part size
try
{
if ((2 * BodyPart.SIZE) > bodySegments[0].Length)
{
return;
}
} catch (IndexOutOfRangeException e)
{
return;
}
// create new body segment with velocity upward
// coords for the segment (same as head)
int[] coords = new int[] { snakeHead.picBox.Location.X, snakeHead.picBox.Location.Y };
Vector newVelocity = new Vector(Velocity.Magnitude, degrees);// velocity for new segment (same magnitude but different velocity)
BodySegment newSegment = new BodySegment(BodyPart.SIZE, BodyPart.SIZE, coords, newVelocity, mainForm);
// make the new segment red if the snake is red
if (red)
{
newSegment.picBox.BackColor = System.Drawing.Color.Red;
newSegment.picBox.Image = null;
}
bodySegments.Insert(0, newSegment); // add it as the first item
clipPrev(); // clip off the previous first item to correct for size
snakeHead.velocity = newVelocity.Clone(); // snakehead velocity same as the first part
correctMovement(); // correct all movement
interval.Start(); // start timer
FixHead(); // correct snake head
}
void ContinuedRun(BodyPart snakeHead, List <ContinuousSnake> snakes, List <Obstacle> obstacles)
{
// get x and y comps of velocity
double thisX = picBox.Location.X + (double)picBox.Width / (double)2;
double thisY = picBox.Location.Y + (double)picBox.Height / (double)2;
double snakeX = snakeHead.picBox.Location.X + (double)snakeHead.picBox.Width / (double)2;
double snakeY = snakeHead.picBox.Location.Y + (double)snakeHead.picBox.Height / (double)2;
// get the comps
double deltaX = snakeX - thisX;
double deltaY = snakeY - thisY;
// scale them according to target velocity magnitude
double triMag = Math.Sqrt(Math.Pow(deltaX, 2) + Math.Pow(deltaY, 2));
deltaX = deltaX * velocityMag / triMag;
deltaY = deltaY * velocityMag / triMag;
// run checks here for obstacles
foreach (Obstacle obstacle in obstacles)
{
// get the rectangle that represents collision area with an obstacle
Rectangle collision = Rectangle.Intersect(obstacle.picBox.Bounds, picBox.Bounds);
if (collision != Rectangle.Empty) // only run if collision is existent
{
if (collision.Width > collision.Height)
{
deltaY = 0;
// push the enemy out by the height
if (collision.Y > picBox.Location.Y)
{
picBox.Location = new Point(picBox.Location.X, picBox.Location.Y - collision.Height - 1);
}
else if (collision.Y < picBox.Location.Y)
{
picBox.Location = new Point(picBox.Location.X, picBox.Location.Y + collision.Height + 1);
}
}
else if (collision.Height > collision.Width)
{
deltaX = 0;
if (collision.X > picBox.Location.X)
{
picBox.Location = new Point(picBox.Location.X - collision.Width - 1, picBox.Location.Y);
}
else if (collision.Y < picBox.Location.Y)
{
picBox.Location = new Point(picBox.Location.X + collision.Width + 1, picBox.Location.Y);
}
}
else
{
//deltaX = 0;
//deltaY = 0;
}
}
}
// run checks here for snakes
foreach (ContinuousSnake snake in snakes)
{
// get body segment that the enemy collided with
BodySegment segment = snake.CollidedWith(picBox);
// end the current loop if no segment returned
if (segment == null)
{
continue;
}
// get the rectangle that represents collision area with an obstacle
Rectangle collision = Rectangle.Intersect(segment.picBox.Bounds, picBox.Bounds);
if (collision != Rectangle.Empty) // only run if collision is existent
{
if (collision.Width > collision.Height)
{
deltaY = 0;
}
else if (collision.Height > collision.Width)
{
deltaX = 0;
}
else
{
//deltaX = 0;
//deltaY = 0;
}
}
}
// move the picturebox
picBox.Location = new System.Drawing.Point((int)(picBox.Location.X + deltaX), (int)(picBox.Location.Y + deltaY));
}