netradiant-custom/radiant/view.h

/*
   Copyright (C) 2001-2006, William Joseph.
   All Rights Reserved.

   This file is part of GtkRadiant.

   GtkRadiant is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.

   GtkRadiant is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with GtkRadiant; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

#pragma once

#include "cullable.h"
#include "math/frustum.h"


#if defined( _DEBUG ) && !defined( _DEBUG_QUICKER )
#define DEBUG_CULLING
#endif


#if defined( DEBUG_CULLING )

extern int g_count_dots;
extern int g_count_planes;
extern int g_count_oriented_planes;
extern int g_count_bboxs;
extern int g_count_oriented_bboxs;

#endif

inline void debug_count_dot(){
#if defined( DEBUG_CULLING )
	++g_count_dots;
#endif
}

inline void debug_count_plane(){
#if defined( DEBUG_CULLING )
	++g_count_planes;
#endif
}

inline void debug_count_oriented_plane(){
#if defined( DEBUG_CULLING )
	++g_count_oriented_planes;
#endif
}

inline void debug_count_bbox(){
#if defined( DEBUG_CULLING )
	++g_count_bboxs;
#endif
}

inline void debug_count_oriented_bbox(){
#if defined( DEBUG_CULLING )
	++g_count_oriented_bboxs;
#endif
}




/// \brief View-volume culling and transformations.
class View : public VolumeTest
{
/// modelview matrix
	Matrix4 m_modelview;
/// projection matrix
	Matrix4 m_projection;
/// device-to-screen transform
	Matrix4 m_viewport;

	Matrix4 m_scissor;

/// combined modelview and projection matrix
	Matrix4 m_viewproj;
/// camera position in world space
	Vector4 m_viewer;
/// view frustum in world space
	Frustum m_frustum;

	Vector3 m_viewdir;

	bool m_fill;

	void construct(){
		m_viewproj = matrix4_multiplied_by_matrix4( matrix4_multiplied_by_matrix4( m_scissor, m_projection ), m_modelview );

		m_frustum = frustum_from_viewproj( m_viewproj );
		m_viewer = viewer_from_viewproj( m_viewproj );
		m_viewdir = vector3_normalised( fill()? Vector3( -m_modelview[2], -m_modelview[6], -m_modelview[10] ) : Vector3( m_modelview[2], m_modelview[6], m_modelview[10] ) );
	}
public:
	View( bool fill = false ) :
		m_modelview( g_matrix4_identity ),
		m_projection( g_matrix4_identity ),
		m_scissor( g_matrix4_identity ),
		m_fill( fill ){
	}
	void Construct( const Matrix4& projection, const Matrix4& modelview, std::size_t width, std::size_t height ){
		// modelview
		m_modelview = modelview;

		// projection
		m_projection = projection;

		// viewport
		m_viewport = g_matrix4_identity;
		m_viewport[0] = float(width / 2);
		m_viewport[5] = float(height / 2);
		if ( fabs( m_projection[11] ) > 0.0000001 ) {
			m_viewport[10] = m_projection[0] * m_viewport[0];
		}
		else{
			m_viewport[10] = 1 / m_projection[10];
		}

		construct();
	}
	void EnableScissor( float min_x, float max_x, float min_y, float max_y ){
		m_scissor = g_matrix4_identity;
		m_scissor[0] = static_cast<float>( ( max_x - min_x ) * 0.5 );
		m_scissor[5] = static_cast<float>( ( max_y - min_y ) * 0.5 );
		m_scissor[12] = static_cast<float>( ( min_x + max_x ) * 0.5 );
		m_scissor[13] = static_cast<float>( ( min_y + max_y ) * 0.5 );
		matrix4_full_invert( m_scissor );

		construct();
	}
	void DisableScissor(){
		m_scissor = g_matrix4_identity;

		construct();
	}

	bool TestPoint( const Vector3& point ) const {
		return viewproj_test_point( m_viewproj, point );
	}
	bool TestLine( const Segment& segment ) const {
		return frustum_test_line( m_frustum, segment );
	}
	bool TestPlane( const Plane3& plane ) const {
		debug_count_plane();
		return viewer_test_plane( m_viewer, plane );
	}
	bool TestPlane( const Plane3& plane, const Matrix4& localToWorld ) const {
		debug_count_oriented_plane();
		return viewer_test_transformed_plane( m_viewer, plane, localToWorld );
	}
	VolumeIntersectionValue TestAABB( const AABB& aabb ) const {
		debug_count_bbox();
		return frustum_test_aabb( m_frustum, aabb );
	}
	VolumeIntersectionValue TestAABB( const AABB& aabb, const Matrix4& localToWorld ) const {
		debug_count_oriented_bbox();
		return frustum_intersects_transformed_aabb( m_frustum, aabb, localToWorld );
	}

	const Matrix4& GetViewMatrix() const {
		return m_viewproj;
	}
	const Matrix4& GetViewport() const {
		return m_viewport;
	}
	const Matrix4& GetModelview() const {
		return m_modelview;
	}
	const Matrix4& GetProjection() const {
		return m_projection;
	}

	bool fill() const {
		return m_fill;
	}
	const Vector3& getViewer() const {
		return m_viewer.vec3();
	}
	const Vector3& getViewDir() const {
		return m_viewdir;
	}
	const Frustum& getFrustum() const {
		return m_frustum;
	}
};