From 955723acf10465d46991cce5d7fb141916b386bd Mon Sep 17 00:00:00 2001
From: Atlante45 <clement.brisset@gmail.com>
Date: Mon, 20 Apr 2015 17:21:27 +0200
Subject: [PATCH] RenderableEntityItem uses collision hull in contains

---
 .../src/RenderableModelEntityItem.cpp         | 32 +++++++++++++++++++
 .../src/RenderableModelEntityItem.h           |  2 ++
 libraries/shared/src/GLMHelpers.cpp           |  7 ++++
 libraries/shared/src/GLMHelpers.h             |  2 ++
 4 files changed, 43 insertions(+)

diff --git a/libraries/entities-renderer/src/RenderableModelEntityItem.cpp b/libraries/entities-renderer/src/RenderableModelEntityItem.cpp
index 86b0be4dd8..ab823d090b 100644
--- a/libraries/entities-renderer/src/RenderableModelEntityItem.cpp
+++ b/libraries/entities-renderer/src/RenderableModelEntityItem.cpp
@@ -415,3 +415,35 @@ void RenderableModelEntityItem::computeShapeInfo(ShapeInfo& info) {
     }
 }
 
+bool RenderableModelEntityItem::contains(const glm::vec3& point) const {
+    bool result = EntityItem::contains(point);
+    
+    if (result && _model && _model->getCollisionGeometry()) {
+        const QSharedPointer<NetworkGeometry> collisionNetworkGeometry = _model->getCollisionGeometry();
+        const FBXGeometry& collisionGeometry = collisionNetworkGeometry->getFBXGeometry();
+        
+        auto checkEachPrimitive = [=](FBXMesh& mesh, QVector<int> indices, int primitiveSize) -> bool {
+            for (unsigned int j = 0; j < indices.size(); j += primitiveSize) {
+                if (!isPointBehindTrianglesPlane(point,
+                                                 mesh.vertices[indices[j]],
+                                                 mesh.vertices[indices[j + 1]],
+                                                 mesh.vertices[indices[j + 2]])) {
+                    return false;
+                }
+            }
+            return true;
+        };
+        
+        for (auto mesh : collisionGeometry.meshes) {
+            for (auto part : mesh.parts) {
+                // run through all the triangles and quads
+                if (!checkEachPrimitive(mesh, part.triangleIndices, 3) ||
+                    !checkEachPrimitive(mesh, part.quadIndices, 4)) {
+                    return false;
+                }
+            }
+        }
+    }
+
+    return result;
+}
diff --git a/libraries/entities-renderer/src/RenderableModelEntityItem.h b/libraries/entities-renderer/src/RenderableModelEntityItem.h
index b632357942..ea153a2dd6 100644
--- a/libraries/entities-renderer/src/RenderableModelEntityItem.h
+++ b/libraries/entities-renderer/src/RenderableModelEntityItem.h
@@ -56,6 +56,8 @@ public:
 
     bool isReadyToComputeShape();
     void computeShapeInfo(ShapeInfo& info);
+    
+    virtual bool contains(const glm::vec3& point) const;
 
 private:
     void remapTextures();
diff --git a/libraries/shared/src/GLMHelpers.cpp b/libraries/shared/src/GLMHelpers.cpp
index 4e8fb7d3cd..aed73c1989 100644
--- a/libraries/shared/src/GLMHelpers.cpp
+++ b/libraries/shared/src/GLMHelpers.cpp
@@ -203,6 +203,13 @@ glm::quat rotationBetween(const glm::vec3& v1, const glm::vec3& v2) {
     return glm::angleAxis(angle, axis);
 }
 
+bool isPointBehindTrianglesPlane(glm::vec3 point, glm::vec3 p0, glm::vec3 p1, glm::vec3 p2) {
+    glm::vec3 v1 = p0 - p1, v2 = p2 - p1; // Non-collinear vectors contained in the plane
+    glm::vec3 n = glm::cross(v1, v2); // Plane's normal vector, pointing out of the triangle
+    float d = -glm::dot(n, p0); // Compute plane's equation constant
+    return (glm::dot(n, point) + d) <= 0;
+}
+
 glm::vec3 extractTranslation(const glm::mat4& matrix) {
     return glm::vec3(matrix[3][0], matrix[3][1], matrix[3][2]);
 }
diff --git a/libraries/shared/src/GLMHelpers.h b/libraries/shared/src/GLMHelpers.h
index 50393b7f5f..e3a2c383e2 100644
--- a/libraries/shared/src/GLMHelpers.h
+++ b/libraries/shared/src/GLMHelpers.h
@@ -71,6 +71,8 @@ float angleBetween(const glm::vec3& v1, const glm::vec3& v2);
 
 glm::quat rotationBetween(const glm::vec3& v1, const glm::vec3& v2);
 
+bool isPointBehindTrianglesPlane(glm::vec3 point, glm::vec3 p0, glm::vec3 p1, glm::vec3 p2);
+
 glm::vec3 extractTranslation(const glm::mat4& matrix);
 
 void setTranslation(glm::mat4& matrix, const glm::vec3& translation);