axmol/cocos/2d/CCVertex.cpp

141 lines
4.5 KiB
C++

/****************************************************************************
Copyright (c) 2010-2012 cocos2d-x.org
Copyright (c) 2011 ForzeField Studios S.L
Copyright (c) 2013-2014 Chukong Technologies Inc.
http://www.cocos2d-x.org
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
****************************************************************************/
#include "CCVertex.h"
#include "ccMacros.h"
NS_CC_BEGIN
void ccVertexLineToPolygon(Vector2 *points, float stroke, Vector2 *vertices, unsigned int offset, unsigned int nuPoints)
{
nuPoints += offset;
if(nuPoints<=1) return;
stroke *= 0.5f;
unsigned int idx;
unsigned int nuPointsMinus = nuPoints-1;
for(unsigned int i = offset; i<nuPoints; i++)
{
idx = i*2;
Vector2 p1 = points[i];
Vector2 perpVector;
if(i == 0)
perpVector = (p1 - points[i+1]).normalize().getPerp();
else if(i == nuPointsMinus)
perpVector = (points[i-1] - p1).normalize().getPerp();
else
{
Vector2 p2 = points[i+1];
Vector2 p0 = points[i-1];
Vector2 p2p1 = (p2 - p1).normalize();
Vector2 p0p1 = (p0 - p1).normalize();
// Calculate angle between vectors
float angle = acosf(p2p1.dot(p0p1));
if(angle < CC_DEGREES_TO_RADIANS(70))
perpVector = p2p1.getMidpoint(p0p1).normalize().getPerp();
else if(angle < CC_DEGREES_TO_RADIANS(170))
perpVector = p2p1.getMidpoint(p0p1).normalize();
else
perpVector = (p2 - p0).normalize().getPerp();
}
perpVector = perpVector * stroke;
vertices[idx] = Vector2(p1.x+perpVector.x, p1.y+perpVector.y);
vertices[idx+1] = Vector2(p1.x-perpVector.x, p1.y-perpVector.y);
}
// Validate vertexes
offset = (offset==0) ? 0 : offset-1;
for(unsigned int i = offset; i<nuPointsMinus; i++)
{
idx = i*2;
const unsigned int idx1 = idx+2;
Vector2 p1 = vertices[idx];
Vector2 p2 = vertices[idx+1];
Vector2 p3 = vertices[idx1];
Vector2 p4 = vertices[idx1+1];
float s;
//BOOL fixVertex = !ccpLineIntersect(Vector2(p1.x, p1.y), Vector2(p4.x, p4.y), Vector2(p2.x, p2.y), Vector2(p3.x, p3.y), &s, &t);
bool fixVertex = !ccVertexLineIntersect(p1.x, p1.y, p4.x, p4.y, p2.x, p2.y, p3.x, p3.y, &s);
if(!fixVertex)
if (s<0.0f || s>1.0f)
fixVertex = true;
if(fixVertex)
{
vertices[idx1] = p4;
vertices[idx1+1] = p3;
}
}
}
bool ccVertexLineIntersect(float Ax, float Ay,
float Bx, float By,
float Cx, float Cy,
float Dx, float Dy, float *T)
{
float distAB, theCos, theSin, newX;
// FAIL: Line undefined
if ((Ax==Bx && Ay==By) || (Cx==Dx && Cy==Dy)) return false;
// Translate system to make A the origin
Bx-=Ax; By-=Ay;
Cx-=Ax; Cy-=Ay;
Dx-=Ax; Dy-=Ay;
// Length of segment AB
distAB = sqrtf(Bx*Bx+By*By);
// Rotate the system so that point B is on the positive X axis.
theCos = Bx/distAB;
theSin = By/distAB;
newX = Cx*theCos+Cy*theSin;
Cy = Cy*theCos-Cx*theSin; Cx = newX;
newX = Dx*theCos+Dy*theSin;
Dy = Dy*theCos-Dx*theSin; Dx = newX;
// FAIL: Lines are parallel.
if (Cy == Dy) return false;
// Discover the relative position of the intersection in the line AB
*T = (Dx+(Cx-Dx)*Dy/(Dy-Cy))/distAB;
// Success.
return true;
}
NS_CC_END