Engine directory for ticket #1

Engine/source/lighting/lightQuery.cpp

@@ -0,0 +1,171 @@
+//-----------------------------------------------------------------------------
+// Copyright (c) 2012 GarageGames, LLC
+//
+// 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.
+//-----------------------------------------------------------------------------
+
+#include "platform/platform.h"
+#include "lighting/lightQuery.h"
+
+#include "lighting/lightManager.h"
+#include "platform/profiler.h"
+
+
+LightQuery::LightQuery( U32 maxLights )
+   : mMaxLights( maxLights )
+{
+}
+
+LightQuery::~LightQuery()
+{
+}
+
+void LightQuery::init(  const Point3F &cameraPos,
+                        const Point3F &cameraDir, 
+                        F32 viewDist )
+{
+   mVolume.center = cameraPos;
+   mVolume.radius = viewDist;
+   mLights.clear();
+}
+
+void LightQuery::init( const SphereF &bounds )
+{
+   mVolume = bounds;
+   mLights.clear();
+}
+
+void LightQuery::init( const Box3F &bounds )
+{
+   bounds.getCenter( &mVolume.center );
+   mVolume.radius = ( bounds.maxExtents - mVolume.center ).len();
+   mLights.clear();
+}
+
+void LightQuery::getLights( LightInfo** outLights, U32 maxLights )
+{
+   PROFILE_SCOPE( LightQuery_getLights );
+
+   // Gather lights if we haven't already.
+   if ( mLights.empty() )
+      _scoreLights();
+
+   U32 lightCount = getMin( (U32)mLights.size(), getMin( mMaxLights, maxLights ) );
+
+   // Copy them over.
+   for ( U32 i = 0; i < lightCount; i++ )
+   {
+      LightInfo *light = mLights[i];
+
+      // If the score reaches zero then we got to
+      // the end of the valid lights for this object.
+      if ( light->getScore() <= 0.0f )
+         break;
+
+      outLights[i] = light;
+   }
+}
+
+void LightQuery::_scoreLights()
+{
+   PROFILE_SCOPE( LightQuery_scoreLights );
+
+   if ( !LIGHTMGR )
+      return;
+
+   // Get all the lights.
+   LIGHTMGR->getAllUnsortedLights( &mLights );
+   LightInfo *sun = LIGHTMGR->getSpecialLight( LightManager::slSunLightType );
+
+   const Point3F lumDot( 0.2125f, 0.7154f, 0.0721f );
+
+   Vector<LightInfo*>::iterator iter = mLights.begin();
+   for ( ; iter != mLights.end(); iter++ )
+   {
+      // Get the light.
+      LightInfo *light = (*iter);
+
+      F32 luminace = 0.0f;
+      F32 dist = 0.0f;
+      F32 weight = 0.0f;
+
+      const bool isSpot = light->getType() == LightInfo::Spot;
+      const bool isPoint = light->getType() == LightInfo::Point;
+
+      if ( isPoint || isSpot )
+      {
+         // Get the luminocity.
+         luminace = mDot( light->getColor(), lumDot ) * light->getBrightness();
+
+         // Get the distance to the light... score it 1 to 0 near to far.
+         F32 lenSq = ( mVolume.center - light->getPosition() ).lenSquared();
+
+         F32 radiusSq = mSquared( light->getRange().x + mVolume.radius );
+         F32 distSq = radiusSq - lenSq;
+         
+         if ( distSq > 0.0f )
+            dist = mClampF( distSq / ( 1000.0f * 1000.0f ), 0.0f, 1.0f );
+
+         // TODO: This culling is broken... it culls spotlights 
+         // that are actually visible.
+         if ( false && isSpot && dist > 0.0f )
+         {
+            // TODO: I cannot test to see if we're within
+            // the cone without a more detailed test... so
+            // just reject if we're behind the spot direction.
+
+            Point3F toCenter = mVolume.center - light->getPosition();
+            F32 angDot = mDot( toCenter, light->getDirection() );
+            if ( angDot < 0.0f )
+               dist = 0.0f;
+         }
+
+         weight = light->getPriority();
+      }
+      else
+      {
+         // The sun always goes first 
+         // regardless of the settings.
+         if ( light == sun )
+         {
+            weight = F32_MAX;
+            dist = 1.0f;
+            luminace = 1.0f;
+         }
+         else
+         {
+            // TODO: When we have multiple directional 
+            // lights we should score them here.
+         }
+      }
+      
+      // TODO: Manager ambient lights here too!
+
+      light->setScore( luminace * weight * dist );
+   }
+
+   // Sort them!
+   mLights.sort( _lightScoreCmp );
+}
+
+S32 LightQuery::_lightScoreCmp( LightInfo* const *a, LightInfo* const *b )
+{
+   F32 diff = (*a)->getScore() - (*b)->getScore();
+   return diff < 0 ? 1 : diff > 0 ? -1 : 0;
+}