PhysicsIntersectionNormal Class

The following example shows how you can get the normal of the intersection point by using the PhysicsIntersectionNormal 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 PhysicsIntersectionNormal class to get the normal of the intersection point.
• Check, if there is a intersection with an object. The engine.physics.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 PhysicsIntersectionNormal class instance gets the normal of the intersection point. You can get it by using getNormal() function

#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 the instance of the PhysicsIntersectionNormal object to save the result
PhysicsIntersectionNormal intersection = new PhysicsIntersectionNormal();
// create an instance for intersected object and check the intersection
Object object = engine.physics.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 the normal in console
  log.message("normal: %s \n", typeinfo(intersection.getNormal()));
}
/* ... */