Gentoo Forums
Gentoo Forums
Gentoo Forums
Quick Search: in
Operator overloading not resulting in the expected value
View unanswered posts
View posts from last 24 hours

 
Reply to topic    Gentoo Forums Forum Index Portage & Programming
View previous topic :: View next topic  
Author Message
coltson
n00b
n00b


Joined: 15 Oct 2005
Posts: 51

PostPosted: Wed Aug 07, 2013 11:10 pm    Post subject: Operator overloading not resulting in the expected value Reply with quote

I have this code:
Code:
 point intersection = viewRay.origin + t * viewRay.dir;


Here operator overloading is used in two cases, in the multiplication between t and viewRay.dir and between viewRay.origin and the result of t * viewRay.dir

viewRay.dir is an structure of the kind Vector, which it is three floats
Code:
struct Vector {
   float x,y,z;
};


t is a float and viewRay.origin it is an structure of the kind Vector, which also it is three floats
Code:
struct point {
  float x,y,z;
};


So if viewRay.origin has it three floats with the values of 300,300 ,-1000, if viewRay.dir value it is 0,0,1 and t value it is 926,4, I should have:
(300,300,-1000) + 926,4 * (0,0,1) = (300,300,-1000) + (0,0,926,4) = (300,300,-73,5595).

However this is not the value that I am getting. Here is the output of the program for viewRay.origin being (300,300,-1000):
Quote:
t value it is: 926.44
viewRay.dir.x value it is: 0 viewRay.dir.y value it is: 0 viewRay.dir.z value it is: 1
viewRay.origin.x value it is: 300 viewRay.origin.x value it is: 300 viewRay.origin.z value it is: -1000
300 300 -73.5595
300 300 -2000


These lines are generated by the first line that I posted in this topic followed by these:
Code:

             point intersection = viewRay.origin + t * viewRay.dir; //already posted this
             cout << "t value it is: " << t << endl;
             cout << " viewRay.dir.x value it is: " << viewRay.dir.x << " viewRay.dir.y value it is: " << viewRay.dir.y << " viewRay.dir.z value it is: " << viewRay.dir.z << endl;
             cout << " viewRay.origin.x value it is: " << viewRay.origin.x << " viewRay.origin.x value it is: " << viewRay.origin.y << " viewRay.origin.z value it is: " << viewRay.origin.z << endl;
             cout << viewRay.origin.x + t*viewRay.dir.x << ' ' << viewRay.origin.y + t*viewRay.dir.y << ' ' << viewRay.origin.z + t*viewRay.dir.z << endl;
             cout << intersection.x << ' ' << intersection.y << ' ' << intersection.z << endl;


So the value being calculated by using operator overloading is
Quote:
300,300,-2000
. The first two values, 300,300 are correct but the last one is wrong. This 2000 is the default value of t, so I thought the t value was wrong, but it is not, as can be seen by the second line of the output
In fifth I calculate the values "manually", without operator overloading and the values calculated are corrects.

So I think the error might be in the operator overloading for the multiplication. Here is the code
Code:
inline Vector operator * (float t, const Vector &v1) {
        Vector v2 = {v1.x * t, v1.y * t, v1.z*t};
        return v2;
  }

I can't see anything wrong there....... So anyone has an idea?

Thanks for any help.
Back to top
View user's profile Send private message
MustrumR
n00b
n00b


Joined: 15 Nov 2011
Posts: 45
Location: Right here

PostPosted: Thu Aug 08, 2013 8:50 am    Post subject: Reply with quote

Please post all the code.
Back to top
View user's profile Send private message
steveL
Advocate
Advocate


Joined: 13 Sep 2006
Posts: 2164
Location: The Peanut Gallery

PostPosted: Thu Aug 08, 2013 6:08 pm    Post subject: Re: Operator overloading not resulting in the expected value Reply with quote

coltson wrote:
Code:
 point intersection = viewRay.origin + t * viewRay.dir;


Here operator overloading is used in two cases, in the multiplication between t and viewRay.dir and between viewRay.origin and the result of t * viewRay.dir

viewRay.dir is an structure of the kind Vector, which it is three floats
Code:
struct Vector {
   float x,y,z;
};


t is a float and viewRay.origin it is an structure of the kind Vector, which also it is three floats
Code:
struct point {
  float x,y,z;
};


It's not though: it's a struct point, same as intersection.
Back to top
View user's profile Send private message
coltson
n00b
n00b


Joined: 15 Oct 2005
Posts: 51

PostPosted: Sat Aug 10, 2013 1:30 am    Post subject: Reply with quote

MustrumR wrote:
Please post all the code.


The code seems to be too big to post it all here at once (more than 600 lines divided into multiple files) How you suggest I shall proceed in this case?

Quote:
It's not though: it's a struct point, same as intersection.


True, my mistake
Back to top
View user's profile Send private message
Hu
Watchman
Watchman


Joined: 06 Mar 2007
Posts: 8617

PostPosted: Sat Aug 10, 2013 1:31 am    Post subject: Reply with quote

Concatenate it into a single file, upload it to a pastebin, and link to the pastebin from here.
Back to top
View user's profile Send private message
coltson
n00b
n00b


Joined: 15 Oct 2005
Posts: 51

PostPosted: Mon Aug 12, 2013 5:07 am    Post subject: Reply with quote

I did it: here is the link: http://codepad.org/64AYV50l

The lines that I mentioned here are in the first 50 lines and between the 538 and the 545 one

To run the program you also need a txt file with this content in the same dir.

Quote:
Image
Width=640;
Height=480;
bpp=32;

Material
{
Diffuse=1.0,1.0,0.0;
Reflection=0.5;
}

Material
{
Diffuse=0.0,1.0,1.0;
Reflection=0.5;
}

Material
{
Diffuse=1.0,0.0,1.0;
Reflection=0.5;
}

///////////////////////////////////////
// List of spheres //
///////////////////////////////////////
Sphere
{
Center=233.0,290.0,0.0;
Radius_Squared=10000;
Size=100.0;
MaterialId=0.0;
}

Sphere
{
Center=407.0,290.0,0.0;
Radius_Squared=10000;
Size=100.0;
MaterialId=1.0;
}

Sphere
{
Center=320.0,140.0,0.0;
Radius_Squared=10000;
Size=100.0;
MaterialId=2.0;
}

///////////////////////////////////////
// List of lights //
///////////////////////////////////////
Light
{
Position=0.0,240.0,-100.0;
Intensity=1.0,1.0,1.0;
}

Light
{
Position=640.0,240.0,-10000.0;
Intensity=0.6,0.7,1.0;
}

Back to top
View user's profile Send private message
Genone
Retired Dev
Retired Dev


Joined: 14 Mar 2003
Posts: 8995
Location: beyond the rim

PostPosted: Mon Aug 12, 2013 6:57 am    Post subject: Reply with quote

Code:
 inline point operator + (const point &p1, const Vector &v1 ) {
      point p2 = {p1.x + v1.x, p1.y + v1.y, p1.z + p1.z};
      return p2;
 }

Typo in the variable name on the z-addition.
Back to top
View user's profile Send private message
coltson
n00b
n00b


Joined: 15 Oct 2005
Posts: 51

PostPosted: Thu Aug 15, 2013 5:07 am    Post subject: Reply with quote

thanks
Back to top
View user's profile Send private message
Display posts from previous:   
Reply to topic    Gentoo Forums Forum Index Portage & Programming All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum