magnum/src/DebugTools/ForceRenderer.h

#ifndef Magnum_DebugTools_ForceRenderer_h
#define Magnum_DebugTools_ForceRenderer_h
/*
    This file is part of Magnum.

    Copyright © 2010, 2011, 2012, 2013 Vladimír Vondruš <mosra@centrum.cz>

    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.
*/

/** @file
 * @brief Class Magnum::DebugTools::ForceRenderer, Magnum::DebugTools::ForceRendererOptions, typedef Magnum::DebugTools::ForceRenderer2D, Magnum::DebugTools::ForceRenderer3D
 */

#include "Color.h"
#include "Resource.h"
#include "SceneGraph/Drawable.h"
#include "Shaders/Shaders.h"

#include "magnumDebugToolsVisibility.h"

namespace Magnum { namespace DebugTools {

/**
@brief Force renderer options

See ForceRenderer documentation for more information.
*/
class ForceRendererOptions {
    public:
        inline constexpr ForceRendererOptions(): _color(1.0f), _size(1.0f) {}

        /** @brief Color of rendered arrow */
        inline constexpr Color4<> color() const { return _color; }

        /**
         * @brief Set color of rendered arrow
         * @return Pointer to self (for method chaining)
         *
         * Default is 100% opaque white.
         */
        inline ForceRendererOptions* setColor(const Color4<>& color) {
            _color = color;
            return this;
        }

        /** @brief Scale of rendered arrow */
        inline constexpr Float scale() const { return _size; }

        /**
         * @brief Set scale of rendered arrow
         * @return Pointer to self (for method chaining)
         *
         * Default is `1.0f`.
         */
        inline ForceRendererOptions* setSize(Float size) {
            _size = size;
            return this;
        }

    private:
        Color4<> _color;
        Float _size;
};

/**
@brief Force renderer

Visualizes force pushing on object by an arrow of the same direction and size.
See @ref debug-tools-renderers for more information.

@section ForceRenderer-usage Basic usage

Example code:
@code
// Create some options
DebugTools::ResourceManager::instance()->set("my", (new DebugTools::ForceRendererOptions)
    ->setScale(5.0f)->setColor(Color3<>::fromHSV(120.0_degf, 1.0f, 0.7f)));

// Create debug renderer for given object, use "my" options for it
Object3D* object;
Vector3 force;
new DebugTools::ForceRenderer2D(object, {0.3f, 1.5f, -0.7f}, &force, "my", debugDrawables);
@endcode

@see ForceRenderer2D, ForceRenderer3D
*/
template<UnsignedInt dimensions> class MAGNUM_DEBUGTOOLS_EXPORT ForceRenderer: public SceneGraph::Drawable<dimensions> {
    public:
        /**
         * @brief Constructor
         * @param object        Object for which to create debug renderer
         * @param forcePosition Where to render the force, relative to object
         * @param force         Force vector
         * @param options       Options resource key. See
         *      @ref ForceRenderer-usage "class documentation" for more
         *      information.
         * @param drawables     Drawable group
         *
         * The renderer is automatically added to object's features, @p force is
         * saved as reference to original vector and thus it must be available
         * for the whole lifetime of the renderer.
         */
        explicit ForceRenderer(SceneGraph::AbstractObject<dimensions>* object, const typename DimensionTraits<dimensions, Float>::VectorType& forcePosition, const typename DimensionTraits<dimensions, Float>::VectorType* force, ResourceKey options = ResourceKey(), SceneGraph::DrawableGroup<dimensions>* drawables = nullptr);

    protected:
        /** @todoc Remove Float when Doxygen properly treats this as override */
        void draw(const typename DimensionTraits<dimensions, Float>::MatrixType& transformationMatrix, SceneGraph::AbstractCamera<dimensions, Float>* camera) override;

    private:
        const typename DimensionTraits<dimensions, Float>::VectorType forcePosition;
        const typename DimensionTraits<dimensions, Float>::VectorType* const force;

        Resource<ForceRendererOptions> options;
        Resource<AbstractShaderProgram, Shaders::FlatShader<dimensions>> shader;
        Resource<Mesh> mesh;
        Resource<Buffer> vertexBuffer, indexBuffer;
};

/** @brief Two-dimensional force renderer */
typedef ForceRenderer<2> ForceRenderer2D;

/** @brief Three-dimensional force renderer */
typedef ForceRenderer<3> ForceRenderer3D;

}}

#endif