source: downloads/ogre_src_v1-9-0/OgreMain/include/OgreLodConfig.h

/*
 * -----------------------------------------------------------------------------
 * This source file is part of OGRE
 * (Object-oriented Graphics Rendering Engine)
 * For the latest info, see http://www.ogre3d.org/
 *
 * Copyright (c) 2000-2013 Torus Knot Software Ltd
 *
 * 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.
 * -----------------------------------------------------------------------------
 */

#ifndef __LogConfig_H_
#define __LogConfig_H_

#include "OgrePrerequisites.h"
#include "OgreMesh.h"
#include "OgreLodStrategy.h"

namespace Ogre
{
/**
 * @brief Structure for automatic LOD configuration.
 */
struct LodLevel {
        /**
         * @brief Type of the reduction.
         *
         * Note: The vertex count is determined by unique vertices per submesh.
         * A mesh may have duplicate vertices with same position.
         */
        enum VertexReductionMethod {
                /**
                 * @brief Percentage of vertexes to be removed from each submesh.
                 *
                 * Valid range is a number between 0.0 and 1.0
                 */
                VRM_PROPORTIONAL,

                /**
                 * @brief Exact vertex count to be removed from each submesh.
                 *
                 * Pass only integers or it will be rounded.
                 */
                VRM_CONSTANT,

                /**
                 * @brief Reduces the vertices, until the cost is bigger then the given value.
                 *
                 * Collapse cost is equal to the amount of artifact the reduction causes.
                 * This generates the best LOD output, but the collapse cost depends on implementation.
                 */
                VRM_COLLAPSE_COST
        };

        /**
         * @brief Distance to swap the LOD.
         *
         * This depends on LodStrategy.
         */
        Real distance;

        /**
         * @brief Reduction method to use.
         *
         * @see ProgressiveMeshGenerator::VertexReductionMethod
         */
        VertexReductionMethod reductionMethod;

        /**
         * @brief The value, which depends on reductionMethod.
         */
        Real reductionValue;

        /**
         * @brief This is set by ProgressiveMeshGenerator::build() function.
         *
         * Use Mesh::getNumLodLevels() for generated LOD count.
         */
        size_t outUniqueVertexCount;

        /**
         * @brief Whether the LOD level generation was skipped, because it has same vertex count as the previous LOD level.
         */
        bool outSkipped;
};

struct LodConfig {
        MeshPtr mesh;
        LodStrategy* strategy;
        typedef vector<LodLevel>::type LodLevelList;
        LodLevelList levels;
};
}
#endif