@Override
public void start(Scene scene) {
database = new SpatialArray<Vec2>(32);
newSprite(
Color.red,
15,
190,
new SteerSet<Vec2>(
new SteerTo<Vec2>(
500,
slowest =
new TargetSlowest<Vec2>(
database,
null,
100,
200,
false,
32,
SpatialDatabase.ALL_GROUPS,
Vec2.FACTORY)),
new SteerWander2(500, 0, 100, 150, 80)));
for (int i = 0; i < 24; i++) {
SteerSprite lamb =
newSprite(
Color.white,
10,
SteerMath.randomFloat(150, 250),
new SteerWander2(1000, 0, 100, 150, 80));
lamb.position.set(SteerMath.randomFloat(width), SteerMath.randomFloat(height));
database.add(lamb);
}
}
@Override
public Vector getTarget(SteerSubject subject) {
Vector position = target.getTarget(subject);
if (SteerMath.isCircleInView(
subject.getPosition(), subject.getDirection(), fov, position, targetRadius, fovType)) {
return position;
}
return null;
}
@Override
public void getForce(float elapsed, SteerSubject<V> subject, V out) {
future.set(leader.getPosition());
future.add(leader.getVelocity());
SteerMath.closest(leader.getPosition(), future, subject.getPosition(), closest);
float distanceSq = closest.dot(subject.getPosition());
if (distanceSq <= distance * distance) {
away(subject, closest, out, this);
}
}
@Override
public void draw(GameState state, Graphics2D gr, Scene scene) {
float radius = 200.0f;
Vec2 upper = new Vec2(fov.x, fov.y);
Vec2 lower = new Vec2(fov.x, -fov.y);
Vec2 upperRotated = upper.rotate(direction);
Vec2 lowerRotated = lower.rotate(direction);
/*
Vec2 towards = target.sub( origin );
float ut = upperRotated.cross( towards );
float lt = lowerRotated.cross( towards );
boolean view = (ut <= 0 && lt >= 0 ) || (fov.x < 0.0f && ((ut >= 0 && lt >= 0) || (ut <= 0 && lt <= 0)));
boolean circleInView = SteerMath.isCircleInView( origin, direction, fov, circlePos, circleRadius, circleEntirely );
*/
gr.setColor(Color.orange);
line.setLine(
origin.x, origin.y, origin.x + upperRotated.x * radius, origin.y + upperRotated.y * radius);
gr.draw(line);
line.setLine(
origin.x, origin.y, origin.x + lowerRotated.x * radius, origin.y + lowerRotated.y * radius);
gr.draw(line);
drawCircle(gr, upperRotated.mul(radius).addi(origin), 5, Color.orange);
drawCircle(gr, direction.mul(radius).addi(origin), 5, Color.gray);
drawCircle(gr, origin, 5, Color.white);
drawCircle(gr, target, 5, Color.red);
drawCircle(gr, circlePos, circleRadius, Color.yellow);
/*
gr.drawString( String.format( "fov: {%.2f,%.2f}", fov.x, fov.y ), 2, 12 );
gr.drawString( String.format( "origin.distanceSq(target): %.2f", origin.distanceSq( target ) ), 2, 24 );
gr.drawString( String.format( "direction.dot(towards): %.2f", direction.dot(towards) ), 2, 36 );
gr.drawString( String.format( "in view: %s", view ), 2, 48 );
gr.drawString( String.format( "upperRotated.cross( towards ): %.2f", upperRotated.cross( towards ) ), 2, 60 );
gr.drawString( String.format( "lowerRotated.cross( towards ): %.2f", lowerRotated.cross( towards ) ), 2, 72 );
gr.drawString( String.format( "isCircleInView(entirely=%s): %s", circleEntirely, circleInView ), 2, 84 );
*/
Vec2 _V = circlePos.sub(origin);
double _a = _V.dot(direction); // how far along the direction the sphere's center is
double _b = _a * Math.tan(fovAngle); // radius of the cone at _a
double _c =
Math.sqrt(_V.lengthSq() - _a * _a); // distance from center of sphere to axis of the cone
double _d = _c - _b; // distance from center of sphere to the surface of the cone
double _e =
_d
* Math.cos(
fovAngle); // shortest distance from center of the sphere to the surface of the cone
boolean _inview = false;
if (_e >= circleRadius) {
// cull
} else if (_e <= -circleRadius) {
// totally
_inview = true;
} else {
// partially
if (!circleEntirely) {
_inview = true;
}
}
Vec2 farAlong =
SteerMath.closest(origin, direction.mul(radius).addi(origin), circlePos, new Vec2());
line.setLine(origin.x, origin.y, farAlong.x, farAlong.y);
gr.draw(line);
line.setLine(
farAlong.x + direction.y * _a,
farAlong.y - direction.x * _a,
farAlong.x - direction.y * _a,
farAlong.y + direction.x * _a);
gr.draw(line);
line.setLine(farAlong.x, farAlong.y, circlePos.x, circlePos.y);
gr.setColor(Color.blue);
gr.draw(line);
int textY = 0;
gr.setColor(Color.white);
gr.drawString(
String.format("how far along: %.2f (expected=%.2f)", _a, farAlong.distance(origin)),
2,
textY += 12);
gr.drawString(String.format("radius of cone: %.2f", _b), 2, textY += 12);
gr.drawString(
String.format(
"circle->axis of cone: %.2f (expected=%.2f)", _c, farAlong.distance(circlePos)),
2,
textY += 12);
gr.drawString(String.format("circle->surface of cone: %.2f", _d), 2, textY += 12);
gr.drawString(String.format("shortest distance: %.2f", _e), 2, textY += 12);
gr.drawString(
String.format("inview(entirely=%s): %s", circleEntirely, _inview), 2, textY += 12);
gr.drawString(
String.format(
"fov: {%.2f,%.2f}: %.2f (%.2f)", fov.x, fov.y, fovAngle, Math.toDegrees(fovAngle)),
2,
textY += 12);
gr.drawString(
String.format(
"isCircleInView: %s",
SteerMath.isCircleInView(
origin,
direction,
Math.tan(fovAngle),
Math.cos(fovAngle),
circlePos,
circleRadius,
circleEntirely)),
2,
textY += 12);
}