Torque2D/engine/source/2d/sceneobject/LightObject.cc

#include "graphics/dgl.h"
#include "console/consoleTypes.h"
#include "2d/core/Utility.h"
#include "2d/sceneobject/LightObject.h"

// Script bindings.
#include "LightObject_ScriptBinding.h"

IMPLEMENT_CONOBJECT(LightObject);

LightObject::LightObject():
   mLightRadius(10.0f),
   mLightSegments(15)
{
   mSrcBlendFactor = GL_SRC_ALPHA;
   mDstBlendFactor = GL_ONE;
   // Use a static body by default.
   mBodyDefinition.type = b2_staticBody;
}

LightObject::~LightObject()
{

}

bool LightObject::onAdd()
{
   // Call Parent.
   if (!Parent::onAdd())
      return false;

   // Return Okay.
   return true;
}

//----------------------------------------------------------------------------

void LightObject::onRemove()
{
   // Call Parent.
   Parent::onRemove();
}

void LightObject::initPersistFields()
{
   Parent::initPersistFields();

   /// Light settings.
   addProtectedField("LightRadius", TypeF32, Offset(mLightRadius, LightObject), &setLightRadius, &defaultProtectedGetFn, &writeLightRadius, "");
   addProtectedField("LightSegments", TypeS32, Offset(mLightSegments, LightObject), &setLightSegments, &defaultProtectedGetFn, &writeLightSegments, "");

}

void LightObject::safeDelete(void)
{
   Parent::safeDelete();
}

void LightObject::sceneRender(const SceneRenderState * sceneRenderState, const SceneRenderRequest * sceneRenderRequest, BatchRender * batchRender)
{
   Vector2 worldPos = getPosition();
   Vector<Vector2> verts;
   Vector<RayList> bList;
   S32 mSrcLightBlend = getSrcBlendFactor();
   S32 mDstLightBlend = getDstBlendFactor();
   ColorF mLightColor = getBlendColor();

   F32 radius = getLightRadius();
   Scene* scene = getScene();
   b2World* mWorld = scene->getWorld();


   

   glEnable(GL_BLEND);
   glDisable(GL_TEXTURE_2D);
   glPushMatrix();
 
   glTranslatef(worldPos.x, worldPos.y, 0);
   glPolygonMode(GL_FRONT, GL_FILL);

   //additive blending
   //glBlendFunc(GL_ONE,GL_ONE);
   
   glBlendFunc(mSrcLightBlend, mDstLightBlend);
   // Creates the fading dark region.
   glBegin(GL_TRIANGLE_FAN);
   glColor4f(mLightColor.red,mLightColor.green,mLightColor.blue,mLightColor.alpha);
   glVertex2f(0, 0);
   //check scene objects
   U32 objCount = scene->getSceneObjectCount();
   for (U32 i = 0; i < objCount; i++)
   {
      SceneObject *tObj = scene->getSceneObject(i);
      Vector2 dist = worldPos - tObj->getPosition();
      const F32 distSqr = dist.LengthSquared();
      const F32 radSqr = radius * radius;
      //within radius?
      if (distSqr < radSqr || distSqr == radSqr)
      {
         U32 shapeCount = tObj->getCollisionShapeCount();
         for (U32 j = 0; j < shapeCount; j++)
         {
            //All vertices from polygon collision shape
            if (tObj->getCollisionShapeType(j) == b2Shape::e_polygon)
            {
               U32 pCount = tObj->getPolygonCollisionShapePointCount(j);

               for (U32 k = 0; k < pCount; k++)
               {
                  Vector2 locPoint = tObj->getPolygonCollisionShapeLocalPoint(j, k);
                  Vector2 wPoint = tObj->getWorldPoint(locPoint);
                  verts.push_back(wPoint);
               }
            }
         }
      }
   }
   ///  \ | /
   /// -  +  -
   ///  / | \

   U32 lightSeg = getLightSegments();
   F32 segAng = 360.0f / lightSeg;

   for (U32 i = 0; i <= lightSeg; i++)
   {
      b2Vec2 segStrt = worldPos;
      b2Vec2 segEnd = segStrt + radius * b2Vec2(mCos(mDegToRad((F32)segAng * i)), mSin(mDegToRad((F32)segAng * i)));
      verts.push_back(segEnd);
   }

   //cast ray to vertices
   for (S32 l = 0; l < verts.size(); l++)
   {
      F32 rayLength = radius;
      Vector2 p1 = worldPos;
      Vector2 p2 = verts[l];
      F32 baseAng = mAtan(p2.x, p2.y);
      F32 cAng = 0;
      for (int m = 0; m < 2; m++)
      {
         if (m == 0)cAng = baseAng - 0.0001f;
         //if (m == 1)cAng = baseAng;
         if (m == 1)cAng = baseAng + 0.0001f;

         p2.x = rayLength * mCos(cAng);
         p2.y = rayLength * mSin(cAng);

         RaysCastCallback callback;
         mWorld->RayCast(&callback, p1, p2);
         if (callback.m_fixture)
         {

            F32 ang = mAtan(callback.m_point.x - p1.x, callback.m_point.y - p1.y);
            Vector2 intersection = p1 + callback.m_fraction * (p2 - p1);
            
            RayList intersectionPoint;
            intersectionPoint.ang = ang;
            intersectionPoint.x = intersection.x;
            intersectionPoint.y = intersection.y;
            intersectionPoint.l = callback.m_fraction;


            bList.push_back_unique(intersectionPoint);

         }
         else
         {
            F32 ang = mAtan(p2.x - p1.x, p2.y - p1.y);

            RayList intersectionPoint;
            intersectionPoint.ang = ang;
            intersectionPoint.x = p2.x;
            intersectionPoint.y = p2.y;
            intersectionPoint.l = 1.0;

            bList.push_back_unique(intersectionPoint);
         }
      }
   }

   //Con::printf("Rays cast: %i", bList.size());
   //sort the list
   if (bList.size() > 1)
   {
      dQsort(bList.address(), bList.size(), sizeof(RayList), sortRays);
   }

   

   //triangle fan
   for (S32 m = 0; m < bList.size(); m++)
   {
      glColor4f(mLightColor.red - (mLightColor.red * bList[m].l), mLightColor.green - (mLightColor.green * bList[m].l), mLightColor.blue - (mLightColor.blue * bList[m].l), mLightColor.alpha - (mLightColor.alpha * bList[m].l));
      glVertex2f(bList[m].x, bList[m].y);

   }
   //close off the circle
   glColor4f(mLightColor.red - (mLightColor.red * bList[0].l), mLightColor.green - (mLightColor.green * bList[0].l), mLightColor.blue - (mLightColor.blue * bList[0].l), mLightColor.alpha - (mLightColor.alpha * bList[0].l));
   glVertex2f(bList[0].x, bList[0].y);

   glDisable(GL_BLEND);

   glEnd();

   glPopMatrix();
}

void LightObject::OnRegisterScene(Scene* mScene)
{
   Parent::OnRegisterScene(mScene);
   mScene->getWorldQuery()->addAlwaysInScope(this);

}

void LightObject::OnUnregisterScene(Scene* mScene)
{
   mScene->getWorldQuery()->removeAlwaysInScope(this);
   Parent::OnUnregisterScene(mScene);
}

S32 QSORT_CALLBACK sortRays(const void* a, const void* b)
{
   RayList* ray_a = (RayList*) a;
   RayList* ray_b = (RayList*) b;

   if (ray_a->ang < ray_b->ang)
   {
      return -1;
   }
   else if (ray_a->ang > ray_b->ang)
   {
      return 1;
   }
  
   return 0;

}