axmol/tests/cpp-tests/Classes/BugsTest/Bug-1174.cpp

/****************************************************************************
 Copyright (c) 2017-2018 Xiamen Yaji Software Co., Ltd.
 
 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.
 ****************************************************************************/

//
// Bug-1174
// http://code.google.com/p/cocos2d-iphone/issues/detail?id=1174
//

#include "Bug-1174.h"

USING_NS_CC;

int check_for_error( Vec2 p1, Vec2 p2, Vec2 p3, Vec2 p4, float s, float t );

int check_for_error( Vec2 p1, Vec2 p2, Vec2 p3, Vec2 p4, float s, float t )
{
    //    the hit point is        p3 + t * (p4 - p3);
    //    the hit point also is    p1 + s * (p2 - p1);
    
    auto p4_p3 = p4 - p3;
    auto p4_p3_t = p4_p3 * t;
    auto hitPoint1 = p3 + p4_p3_t;
    
    auto p2_p1 = p2 - p1;
    auto p2_p1_s = p2_p1 * s;
    auto hitPoint2 = p1 + p2_p1_s;
    
    // Since float has rounding errors, only check if diff is < 0.05
    if( (fabs( hitPoint1.x - hitPoint2.x) > 0.1f) || ( fabs(hitPoint1.y - hitPoint2.y) > 0.1f) )
    {
        log("ERROR: (%f,%f) != (%f,%f)", hitPoint1.x, hitPoint1.y, hitPoint2.x, hitPoint2.y);
        return 1;
    }

    return 0;
}

bool Bug1174Layer::init()
{
    if (BugsTestBase::init())
    {
//         // seed
//         std::srand(0);

        Vec2 A,B,C,D,p1,p2,p3,p4;
        float s,t;
        
        int err=0;
        int ok=0;
        
        //
        // Test 1.
        //
        log("Test1 - Start");
        for( int i=0; i < 10000; i++)
        {
            // A | b
            // -----
            // c | d
            float ax = CCRANDOM_0_1() * -5000;
            float ay = CCRANDOM_0_1() * 5000;

            // a | b
            // -----
            // c | D
            float dx = CCRANDOM_0_1() * 5000;
            float dy = CCRANDOM_0_1() * -5000;

            // a | B
            // -----
            // c | d
            float bx = CCRANDOM_0_1() * 5000;
            float by = CCRANDOM_0_1() * 5000;
            
            // a | b
            // -----
            // C | d
            float cx = CCRANDOM_0_1() * -5000;
            float cy = CCRANDOM_0_1() * -5000;
            
            A = Vec2(ax,ay);
            B = Vec2(bx,by);
            C = Vec2(cx,cy);
            D = Vec2(dx,dy);
            if( Vec2::isLineIntersect( A, D, B, C, &s, &t) ) {
                if( check_for_error(A, D, B, C, s, t) )
                    err++;
                else
                    ok++;
            }
        }
        log("Test1 - End. OK=%i, Err=%i", ok, err);

        //
        // Test 2.
        //
        log("Test2 - Start");
        
        p1 = Vec2(220,480);
        p2 = Vec2(304,325);
        p3 = Vec2(264,416);
        p4 = Vec2(186,416);
        s = 0.0f;
        t = 0.0f;
        if( Vec2::isLineIntersect(p1, p2, p3, p4, &s, &t) )
            check_for_error(p1, p2, p3, p4, s,t );

        log("Test2 - End");

        
        //
        // Test 3
        //
        log("Test3 - Start");
        
        ok=0;
        err=0;
        for( int i=0;i<10000;i++)
        {
            // A | b
            // -----
            // c | d
            float ax = CCRANDOM_0_1() * -500;
            float ay = CCRANDOM_0_1() * 500;
            p1 = Vec2(ax,ay);
            
            // a | b
            // -----
            // c | D
            float dx = CCRANDOM_0_1() * 500;
            float dy = CCRANDOM_0_1() * -500;
            p2 = Vec2(dx,dy);
            
            
            //////
            
            float y = ay - ((ay - dy) /2.0f);

            // a | b
            // -----
            // C | d
            float cx = CCRANDOM_0_1() * -500;
            p3 = Vec2(cx,y);
            
            // a | B
            // -----
            // c | d
            float bx = CCRANDOM_0_1() * 500;
            p4 = Vec2(bx,y);

            s = 0.0f;
            t = 0.0f;
            if( Vec2::isLineIntersect(p1, p2, p3, p4, &s, &t) ) {
                if( check_for_error(p1, p2, p3, p4, s,t ) )
                    err++;
                else
                    ok++;
            }
        }
        
        log("Test3 - End. OK=%i, err=%i", ok, err);
        return true;
    }

    return false;
}