/// <summary>Adjusts the parent and child bone rotations so the tip of the child is as close to the target position as
/// possible. The target is specified in the world coordinate system.</summary>
/// <param name="child">Any descendant bone of the parent.</param>
static public void apply(Bone parent, Bone child, float targetX, float targetY, int bendDirection, float alpha)
{
float childRotation = child.rotation, parentRotation = parent.rotation;
if (alpha == 0)
{
child.rotationIK = childRotation;
parent.rotationIK = parentRotation;
return;
}
float positionX, positionY;
Bone parentParent = parent.parent;
if (parentParent != null)
{
parentParent.worldToLocal(targetX, targetY, out positionX, out positionY);
targetX = (positionX - parent.x) * parentParent.worldScaleX;
targetY = (positionY - parent.y) * parentParent.worldScaleY;
}
else
{
targetX -= parent.x;
targetY -= parent.y;
}
if (child.parent == parent)
{
positionX = child.x;
positionY = child.y;
}
else
{
child.parent.localToWorld(child.x, child.y, out positionX, out positionY);
parent.worldToLocal(positionX, positionY, out positionX, out positionY);
}
float childX = positionX * parent.worldScaleX, childY = positionY * parent.worldScaleY;
float offset = (float)Math.Atan2(childY, childX);
float len1 = (float)Math.Sqrt(childX * childX + childY * childY), len2 = child.data.length * child.worldScaleX;
// Based on code by Ryan Juckett with permission: Copyright (c) 2008-2009 Ryan Juckett, http://www.ryanjuckett.com/
float cosDenom = 2 * len1 * len2;
if (cosDenom < 0.0001f)
{
child.rotationIK = childRotation + ((float)Math.Atan2(targetY, targetX) * radDeg - parentRotation - childRotation)
* alpha;
return;
}
float cos = (targetX * targetX + targetY * targetY - len1 * len1 - len2 * len2) / cosDenom;
if (cos < -1)
{
cos = -1;
}
else if (cos > 1)
{
cos = 1;
}
float childAngle = (float)Math.Acos(cos) * bendDirection;
float adjacent = len1 + len2 * cos, opposite = len2 * (float)Math.Sin(childAngle);
float parentAngle = (float)Math.Atan2(targetY * adjacent - targetX * opposite, targetX * adjacent + targetY * opposite);
float rotation = (parentAngle - offset) * radDeg - parentRotation;
if (rotation > 180)
{
rotation -= 360;
}
else if (rotation < -180) //
{
rotation += 360;
}
parent.rotationIK = parentRotation + rotation * alpha;
rotation = (childAngle + offset) * radDeg - childRotation;
if (rotation > 180)
{
rotation -= 360;
}
else if (rotation < -180) //
{
rotation += 360;
}
child.rotationIK = childRotation + (rotation + parent.worldRotation - child.parent.worldRotation) * alpha;
}
/// <summary>Adjusts the parent and child bone rotations so the tip of the child is as close to the target position as
/// possible. The target is specified in the world coordinate system.</summary>
/// <param name="child">Any descendant bone of the parent.</param>
public static void apply(Bone parent, Bone child, float targetX, float targetY, int bendDirection, float alpha)
{
float childRotation = child.rotation, parentRotation = parent.rotation;
if (alpha == 0) {
child.rotationIK = childRotation;
parent.rotationIK = parentRotation;
return;
}
float positionX, positionY;
Bone parentParent = parent.parent;
if (parentParent != null) {
parentParent.worldToLocal(targetX, targetY, out positionX, out positionY);
targetX = (positionX - parent.x) * parentParent.worldScaleX;
targetY = (positionY - parent.y) * parentParent.worldScaleY;
} else {
targetX -= parent.x;
targetY -= parent.y;
}
if (child.parent == parent) {
positionX = child.x;
positionY = child.y;
} else {
child.parent.localToWorld(child.x, child.y, out positionX, out positionY);
parent.worldToLocal(positionX, positionY, out positionX, out positionY);
}
float childX = positionX * parent.worldScaleX, childY = positionY * parent.worldScaleY;
float offset = (float)Math.Atan2(childY, childX);
float len1 = (float)Math.Sqrt(childX * childX + childY * childY), len2 = child.data.length * child.worldScaleX;
// Based on code by Ryan Juckett with permission: Copyright (c) 2008-2009 Ryan Juckett, http://www.ryanjuckett.com/
float cosDenom = 2 * len1 * len2;
if (cosDenom < 0.0001f) {
child.rotationIK = childRotation + ((float)Math.Atan2(targetY, targetX) * radDeg - parentRotation - childRotation)
* alpha;
return;
}
float cos = (targetX * targetX + targetY * targetY - len1 * len1 - len2 * len2) / cosDenom;
if (cos < -1)
cos = -1;
else if (cos > 1)
cos = 1;
float childAngle = (float)Math.Acos(cos) * bendDirection;
float adjacent = len1 + len2 * cos, opposite = len2 * (float)Math.Sin(childAngle);
float parentAngle = (float)Math.Atan2(targetY * adjacent - targetX * opposite, targetX * adjacent + targetY * opposite);
float rotation = (parentAngle - offset) * radDeg - parentRotation;
if (rotation > 180)
rotation -= 360;
else if (rotation < -180) //
rotation += 360;
parent.rotationIK = parentRotation + rotation * alpha;
rotation = (childAngle + offset) * radDeg - childRotation;
if (rotation > 180)
rotation -= 360;
else if (rotation < -180) //
rotation += 360;
child.rotationIK = childRotation + (rotation + parent.worldRotation - child.parent.worldRotation) * alpha;
}
public static void apply(Bone parent, Bone child, float targetX, float targetY, int bendDirection, float alpha)
{
float rotation = child.rotation;
float rotation2 = parent.rotation;
if (alpha == 0f)
{
child.rotationIK = rotation;
parent.rotationIK = rotation2;
return;
}
Bone parent2 = parent.parent;
float x;
float y;
if (parent2 != null)
{
parent2.worldToLocal(targetX, targetY, out x, out y);
targetX = (x - parent.x) * parent2.worldScaleX;
targetY = (y - parent.y) * parent2.worldScaleY;
}
else
{
targetX -= parent.x;
targetY -= parent.y;
}
if (child.parent == parent)
{
x = child.x;
y = child.y;
}
else
{
child.parent.localToWorld(child.x, child.y, out x, out y);
parent.worldToLocal(x, y, out x, out y);
}
float num = x * parent.worldScaleX;
float num2 = y * parent.worldScaleY;
float num3 = (float)Math.Atan2((double)num2, (double)num);
float num4 = (float)Math.Sqrt((double)(num * num + num2 * num2));
float num5 = child.data.length * child.worldScaleX;
float num6 = 2f * num4 * num5;
if (num6 < 0.0001f)
{
child.rotationIK = rotation + ((float)Math.Atan2((double)targetY, (double)targetX) * 57.2957764f - rotation2 - rotation) * alpha;
return;
}
float num7 = (targetX * targetX + targetY * targetY - num4 * num4 - num5 * num5) / num6;
if (num7 < -1f)
{
num7 = -1f;
}
else if (num7 > 1f)
{
num7 = 1f;
}
float num8 = (float)Math.Acos((double)num7) * (float)bendDirection;
float num9 = num4 + num5 * num7;
float num10 = num5 * (float)Math.Sin((double)num8);
float num11 = (float)Math.Atan2((double)(targetY * num9 - targetX * num10), (double)(targetX * num9 + targetY * num10));
float num12 = (num11 - num3) * 57.2957764f - rotation2;
if (num12 > 180f)
{
num12 -= 360f;
}
else if (num12 < -180f)
{
num12 += 360f;
}
parent.rotationIK = rotation2 + num12 * alpha;
num12 = (num8 + num3) * 57.2957764f - rotation;
if (num12 > 180f)
{
num12 -= 360f;
}
else if (num12 < -180f)
{
num12 += 360f;
}
child.rotationIK = rotation + (num12 + parent.worldRotation - child.parent.worldRotation) * alpha;
}