axmol/cocos/editor-support/spine/IkConstraint.c

217 lines
7.3 KiB
C

/******************************************************************************
* Spine Runtimes Software License v2.5
*
* Copyright (c) 2013-2016, Esoteric Software
* All rights reserved.
*
* You are granted a perpetual, non-exclusive, non-sublicensable, and
* non-transferable license to use, install, execute, and perform the Spine
* Runtimes software and derivative works solely for personal or internal
* use. Without the written permission of Esoteric Software (see Section 2 of
* the Spine Software License Agreement), you may not (a) modify, translate,
* adapt, or develop new applications using the Spine Runtimes or otherwise
* create derivative works or improvements of the Spine Runtimes or (b) remove,
* delete, alter, or obscure any trademarks or any copyright, trademark, patent,
* or other intellectual property or proprietary rights notices on or in the
* Software, including any copy thereof. Redistributions in binary or source
* form must include this license and terms.
*
* THIS SOFTWARE IS PROVIDED BY ESOTERIC SOFTWARE "AS IS" AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
* EVENT SHALL ESOTERIC SOFTWARE BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, BUSINESS INTERRUPTION, OR LOSS OF
* USE, DATA, OR PROFITS) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
* IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*****************************************************************************/
#include <spine/IkConstraint.h>
#include <spine/Skeleton.h>
#include <spine/extension.h>
#include <float.h>
spIkConstraint *spIkConstraint_create(spIkConstraintData *data, const spSkeleton *skeleton) {
int i;
spIkConstraint *self = NEW(spIkConstraint);
CONST_CAST(spIkConstraintData*, self->data) = data;
self->bendDirection = data->bendDirection;
self->mix = data->mix;
self->bonesCount = self->data->bonesCount;
self->bones = MALLOC(spBone*, self->bonesCount);
for (i = 0; i < self->bonesCount; ++i)
self->bones[i] = spSkeleton_findBone(skeleton, self->data->bones[i]->name);
self->target = spSkeleton_findBone(skeleton, self->data->target->name);
return self;
}
void spIkConstraint_dispose(spIkConstraint *self) {
FREE(self->bones);
FREE(self);
}
void spIkConstraint_apply(spIkConstraint *self) {
switch (self->bonesCount) {
case 1:
spIkConstraint_apply1(self->bones[0], self->target->worldX, self->target->worldY, self->mix);
break;
case 2:
spIkConstraint_apply2(self->bones[0], self->bones[1], self->target->worldX, self->target->worldY, self->bendDirection, self->mix);
break;
}
}
void spIkConstraint_apply1 (spBone* bone, float targetX, float targetY, float alpha) {
spBone* p = bone->parent;
float id, x, y, tx, ty, rotationIK;
if (!bone->appliedValid) spBone_updateAppliedTransform(bone);
id = 1 / (p->a * p->d - p->b * p->c);
x = targetX - p->worldX, y = targetY - p->worldY;
tx = (x * p->d - y * p->b) * id - bone->ax; ty = (y * p->a - x * p->c) * id - bone->ay;
rotationIK = ATAN2(ty, tx) * RAD_DEG - bone->ashearX - bone->arotation;
if (bone->ascaleX < 0) rotationIK += 180;
if (rotationIK > 180) rotationIK -= 360;
else if (rotationIK < -180) rotationIK += 360;
spBone_updateWorldTransformWith(bone, bone->ax, bone->ay, bone->arotation + rotationIK * alpha, bone->ascaleX,
bone->ascaleY, bone->ashearX, bone->ashearY);
}
void spIkConstraint_apply2 (spBone* parent, spBone* child, float targetX, float targetY, int bendDir, float alpha) {
float px, py, psx, psy;
float cx, cy, csx, cwx, cwy;
int o1, o2, s2, u;
spBone* pp = parent->parent;
float tx, ty, dx, dy, l1, l2, a1, a2, r;
float id, x, y;
if (alpha == 0) {
spBone_updateWorldTransform(child);
return;
}
if (!parent->appliedValid) spBone_updateAppliedTransform(parent);
if (!child->appliedValid) spBone_updateAppliedTransform(child);
px = parent->ax; py = parent->ay; psx = parent->ascaleX; psy = parent->ascaleY; csx = child->ascaleX;
if (psx < 0) {
psx = -psx;
o1 = 180;
s2 = -1;
} else {
o1 = 0;
s2 = 1;
}
if (psy < 0) {
psy = -psy;
s2 = -s2;
}
if (csx < 0) {
csx = -csx;
o2 = 180;
} else
o2 = 0;
r = psx - psy;
cx = child->ax;
u = (r < 0 ? -r : r) <= 0.0001f;
if (!u) {
cy = 0;
cwx = parent->a * cx + parent->worldX;
cwy = parent->c * cx + parent->worldY;
} else {
cy = child->ay;
cwx = parent->a * cx + parent->b * cy + parent->worldX;
cwy = parent->c * cx + parent->d * cy + parent->worldY;
}
id = 1 / (pp->a * pp->d - pp->b * pp->c);
x = targetX - pp->worldX;
y = targetY - pp->worldY;
tx = (x * pp->d - y * pp->b) * id - px;
ty = (y * pp->a - x * pp->c) * id - py;
x = cwx - pp->worldX;
y = cwy - pp->worldY;
dx = (x * pp->d - y * pp->b) * id - px;
dy = (y * pp->a - x * pp->c) * id - py;
l1 = SQRT(dx * dx + dy * dy);
l2 = child->data->length * csx;
if (u) {
float cosine, a, b;
l2 *= psx;
cosine = (tx * tx + ty * ty - l1 * l1 - l2 * l2) / (2 * l1 * l2);
if (cosine < -1) cosine = -1;
else if (cosine > 1) cosine = 1;
a2 = ACOS(cosine) * bendDir;
a = l1 + l2 * cosine;
b = l2 * SIN(a2);
a1 = ATAN2(ty * a - tx * b, tx * a + ty * b);
} else {
float a = psx * l2, b = psy * l2;
float aa = a * a, bb = b * b, ll = l1 * l1, dd = tx * tx + ty * ty, ta = ATAN2(ty, tx);
float c0 = bb * ll + aa * dd - aa * bb, c1 = -2 * bb * l1, c2 = bb - aa;
float d = c1 * c1 - 4 * c2 * c0;
float minAngle = 0, minDist = FLT_MAX, minX = 0, minY = 0;
float maxAngle = 0, maxDist = 0, maxX = 0, maxY = 0;
float x = l1 + a, dist = x * x, angle, y;
if (d >= 0) {
float q = SQRT(d), r0, r1;
if (c1 < 0) q = -q;
q = -(c1 + q) / 2;
r0 = q / c2; r1 = c0 / q;
r = ABS(r0) < ABS(r1) ? r0 : r1;
if (r * r <= dd) {
y = SQRT(dd - r * r) * bendDir;
a1 = ta - ATAN2(y, r);
a2 = ATAN2(y / psy, (r - l1) / psx);
goto outer;
}
}
if (dist > maxDist) {
maxAngle = 0;
maxDist = dist;
maxX = x;
}
x = l1 - a;
dist = x * x;
if (dist < minDist) {
minAngle = PI;
minDist = dist;
minX = x;
}
angle = ACOS(-a * l1 / (aa - bb));
x = a * COS(angle) + l1;
y = b * SIN(angle);
dist = x * x + y * y;
if (dist < minDist) {
minAngle = angle;
minDist = dist;
minX = x;
minY = y;
}
if (dist > maxDist) {
maxAngle = angle;
maxDist = dist;
maxX = x;
maxY = y;
}
if (dd <= (minDist + maxDist) / 2) {
a1 = ta - ATAN2(minY * bendDir, minX);
a2 = minAngle * bendDir;
} else {
a1 = ta - ATAN2(maxY * bendDir, maxX);
a2 = maxAngle * bendDir;
}
}
outer: {
float os = ATAN2(cy, cx) * s2;
a1 = (a1 - os) * RAD_DEG + o1 - parent->arotation;
if (a1 > 180) a1 -= 360;
else if (a1 < -180) a1 += 360;
spBone_updateWorldTransformWith(parent, px, py, parent->rotation + a1 * alpha, parent->ascaleX, parent->ascaleY, 0, 0);
a2 = ((a2 + os) * RAD_DEG - child->ashearX) * s2 + o2 - child->arotation;
if (a2 > 180) a2 -= 360;
else if (a2 < -180) a2 += 360;
spBone_updateWorldTransformWith(child, cx, cy, child->arotation + a2 * alpha, child->ascaleX, child->ascaleY, child->ashearX, child->ashearY);
}
}