added ambient_occlusion global scene option to parser and vim keywords; added ambient_occlusion scene file

git-svn-id: svn://anubis/fart/trunk@263 7f9b0f55-74a9-4bce-be96-3c2cd072584d

main/Scene-load.cc

@@ -202,6 +202,10 @@ void Scene::processOptions(refptr<Node> node)
         {
             setAmbientLight(Color((*it)->getVector()));
         }
+        else if ( typeid(**it) == typeid(AmbientOcclusionNode) )
+        {
+            m_ambient_occlusion_level = (*it)->getInteger();
+        }
     }
 }
 

main/Scene.cc

@@ -30,6 +30,7 @@ Scene::Scene(const map<string, const char *> & options,
     m_ambient_light = Color(0.2, 0.2, 0.2);
     m_max_depth = 10;
     m_exposure = 1.0f;
+    m_ambient_occlusion_level = 0;
     m_transforms.push(Transform());
 
     load(filename);
@@ -215,8 +216,12 @@ Color Scene::computePhong(const refptr<Material> material,
                           const Vector & surfacePoint,
                           const Vector & surfaceNormal)
 {
-    Color result = m_ambient_light * material->getAmbientColor()
-        * calculateAmbientOcclusion(Ray(surfacePoint, surfaceNormal).shift(1e-7));
+    Color result = m_ambient_light * material->getAmbientColor();
+    if (m_ambient_occlusion_level > 0)
+    {
+        result *= calculateAmbientOcclusion(
+                Ray(surfacePoint, surfaceNormal).shift(1e-7));
+    }
 
     Vector viewDirection = -viewRay.getDirection();
     double shininess = material->getShininess();
@@ -327,7 +332,8 @@ Color Scene::calculateLightContribution(const Ray & toLight,
 Color Scene::calculateAmbientOcclusion(const Ray & surfaceNormal)
 {
     Color result(1, 1, 1);
-    const int nISteps = 30, nJSteps = 15;
+    const int nISteps = m_ambient_occlusion_level * 6;
+    const int nJSteps = nISteps / 2;
     int nRays = 0;
     Vector perpX = surfaceNormal.getDirection().getPerpendicular().normalize();
     Vector perpY = (surfaceNormal.getDirection() * perpX).normalize();

main/Scene.h

@@ -37,6 +37,7 @@ class Scene
         int getWidth() { return m_width; }
         int getHeight() { return m_height; }
         int getMultisampleLevel() { return m_multisample_level; }
+        int getAmbientOcclusionLevel() { return m_ambient_occlusion_level; }
         double getVFOV() { return m_vfov; }
 
     protected:
@@ -79,6 +80,7 @@ class Scene
         Color m_ambient_light;
         int m_max_depth;
         double m_exposure;
+        int m_ambient_occlusion_level;
 
         /* private data */
         std::vector< refptr<Shape> > m_shapes;

main/fart.cc

@@ -187,6 +187,7 @@ int main(int argc, char * argv[])
         cout << "    Width: " << width << endl;
         cout << "    Height: " << height << endl;
         cout << "    Multisample Level: " << scene.getMultisampleLevel() << endl;
+        cout << "    Ambient Occlusion Level: " << scene.getAmbientOcclusionLevel() << endl;
         cout << "    Vertical Field of View: " << scene.getVFOV() << endl;
         cout << "----------------------------------------" << endl;
     }

parser/nodes.h

@@ -68,6 +68,12 @@ class AmbientNode : public VectorNode
         AmbientNode(refptr<Vector> vector) : VectorNode(vector) {}
 };
 
+class AmbientOcclusionNode : public IntegerNode
+{
+    public:
+        AmbientOcclusionNode(int i) : IntegerNode(i) {}
+};
+
 class BoxNode : public Node
 {
     public:

parser/parser.lex

@@ -40,6 +40,7 @@
 -?[0-9]*\.[0-9]+    *yylval = new NumberNode(atof(yytext)); return REAL_NUMBER;
 
 ambient             return AMBIENT;
+ambient_occlusion   return AMBIENT_OCCLUSION;
 box                 return BOX;
 camera              return CAMERA;
 color               return COLOR;

parser/parser.yy

@@ -59,6 +59,7 @@ static refptr<Node> parsed_scene_node;
 %token REAL_NUMBER;
 
 %token AMBIENT;
+%token AMBIENT_OCCLUSION;
 %token BOX;
 %token CAMERA;
 %token COLOR;
@@ -314,6 +315,9 @@ options_item: WIDTH DEC_NUMBER {
             | AMBIENT vector {
                     $$ = new AmbientNode($2->getVector());
                 }
+            | AMBIENT_OCCLUSION DEC_NUMBER {
+                    $$ = new AmbientOcclusionNode($2->getInteger());
+                }
             ;
 
 plane: PLANE LCURLY plane_items RCURLY {

scenes/ambient_occlusion.fart

@@ -0,0 +1,41 @@
+
+scene
+{
+    options
+    {
+        multisample 3
+        width 800
+        height 600
+        ambient_occlusion 5
+    }
+
+    camera
+    {
+        position <2, -3, 2>
+        look_at <0, 0, 1>
+        up <0, 0, 1>
+    }
+
+    light
+    {
+        position <200, -10, 50>
+    }
+
+    define material white
+    {
+        color <1, 1, 1>
+    }
+
+    sphere
+    {
+        radius 1
+        material white
+        translate <0, 0, 1>
+    }
+    
+    plane
+    {
+        position <0, 0, 1>, 0
+        material white
+    }
+}

vim/syntax/fart.vim

@@ -10,7 +10,7 @@ endif
 
 syn case match
 
-syn keyword fartKeywords ambient color define diffuse exposure height jitter look_at material max_depth multisample options position radius reflectance rotate scale shininess size specular translate transparency union up vfov width
+syn keyword fartKeywords ambient ambient_occlusion color define diffuse exposure height jitter look_at material max_depth multisample options position radius reflectance rotate scale shininess size specular translate transparency union up vfov width
 syn keyword fartObjects box camera cyl intersect light plane scene sphere subtract union
 syn match fartNumber "\(^\|\W\)\@<=[+-]\=\(\d\+\)\=\.\=\d\+\([eE][+-]\=\d\+\)\="