maintenance: opengl and generic gfx class source files split

openglcamera.cpp

@@ -0,0 +1,61 @@
+/*
+This Source Code Form is subject to the
+terms of the Mozilla Public License, v.
+2.0. If a copy of the MPL was not
+distributed with this file, You can
+obtain one at
+http://mozilla.org/MPL/2.0/.
+*/
+
+#include "stdafx.h"
+#include "openglcamera.h"
+
+#include "DynObj.h"
+
+void
+opengl_camera::update_frustum( glm::mat4 const &Projection, glm::mat4 const &Modelview ) {
+
+    m_frustum.calculate( Projection, Modelview );
+    // cache inverse tranformation matrix
+    // NOTE: transformation is done only to camera-centric space
+    m_inversetransformation = glm::inverse( Projection * glm::mat4{ glm::mat3{ Modelview } } );
+    // calculate frustum corners
+    m_frustumpoints = ndcfrustumshapepoints;
+    transform_to_world(
+        std::begin( m_frustumpoints ),
+        std::end( m_frustumpoints ) );
+}
+
+// returns true if specified object is within camera frustum, false otherwise
+bool
+opengl_camera::visible( scene::bounding_area const &Area ) const {
+
+    return ( m_frustum.sphere_inside( Area.center, Area.radius ) > 0.f );
+}
+
+bool
+opengl_camera::visible( TDynamicObject const *Dynamic ) const {
+
+    // sphere test is faster than AABB, so we'll use it here
+    glm::vec3 diagonal(
+        static_cast<float>( Dynamic->MoverParameters->Dim.L ),
+        static_cast<float>( Dynamic->MoverParameters->Dim.H ),
+        static_cast<float>( Dynamic->MoverParameters->Dim.W ) );
+    // we're giving vehicles some extra padding, to allow for things like shared bogeys extending past the main body
+    float const radius = glm::length( diagonal ) * 0.65f;
+
+    return ( m_frustum.sphere_inside( Dynamic->GetPosition(), radius ) > 0.0f );
+}
+
+// debug helper, draws shape of frustum in world space
+void
+opengl_camera::draw( glm::vec3 const &Offset ) const {
+
+    ::glBegin( GL_LINES );
+    for( auto const pointindex : frustumshapepoinstorder ) {
+        ::glVertex3fv( glm::value_ptr( glm::vec3{ m_frustumpoints[ pointindex ] } - Offset ) );
+    }
+    ::glEnd();
+}
+
+//---------------------------------------------------------------------------