WorldIntersection Class

The following example shows how you can get the intersection information by using the WorldIntersection class. In this example the line is an invisible traced line from the point of the camera (vec3 p0) to the point of the mouse pointer (vec3 p1). The executing sequence is the following:

• Define and initialize two points (p0 and p1) by using the Unigine::getPlayerMouseDirection() function from core/scripts/utils.h.
• Create an instance of the WorldIntersection class to get the intersection information.
• Check, if there is a intersection with an object. The engine.world.getIntersection() function returns an intersected object when the object intersects with the traced line.
• In this example, when the object intersects with the traced line, all the surfaces of the intersected object change their material parameters. The WorldIntersection class instance gets the coordinates of the intersection point, the index of the surface and the index of the intersected triangle. You can get all these fields by using getIndex(), getPoint() and getSurface() functions

#include <core/scripts/utils.h>
/* ... */
// define two vec3 coordinates
vec3 p0,p1;
// get the mouse direction from camera (p0) to cursor pointer (p1)
Unigine::getPlayerMouseDirection(p0,p1);

// create an instance of the WorldIntersection class to get the result
WorldIntersection intersection = new WorldIntersection();

// create an instance for intersected object and check the intersection
Object object = engine.world.getIntersection(p0,p1,1,intersection);

// if the intersection has been occurred, change the parameter and the texture of the object's material
if(object != NULL)
{
  forloop(int i=0; object.getNumSurfaces())
  {
    object.setMaterialParameter("diffuse_color", vec4(1.0f, 0.0f, 0.0f, 1.0f),i);
    object.setMaterialTexture("diffuse","", i);
    
    // show intersection details in console
    log.message("point: %s index: %i surface: %i \n", typeinfo(intersection.getPoint()), intersection.getIndex(), intersection.getSurface());
  }

}
/* ... */