magnum/src/Magnum/MeshTools/Compile.h

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

    Copyright © 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019
              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 Function @ref Magnum::MeshTools::compile()
 */

#include "Magnum/configure.h"

#ifdef MAGNUM_TARGET_GL
#include <Corrade/Containers/EnumSet.h>

#include "Magnum/Magnum.h"
#include "Magnum/GL/GL.h"
#include "Magnum/Trade/Trade.h"
#include "Magnum/MeshTools/visibility.h"

#ifdef MAGNUM_BUILD_DEPRECATED
#include <tuple>
#include <memory> /* deliberately kept here */
#include <Corrade/Utility/Macros.h>
#endif

namespace Magnum { namespace MeshTools {

/**
@brief Mesh compilation flag
@m_since{2019,10}

@see @ref CompileFlags, @ref compile(const Trade::MeshData&, CompileFlags)
*/
enum class CompileFlag: UnsignedByte {
    /**
     * If the mesh is @ref MeshPrimitive::Triangles, generates normals using
     * @ref MeshTools::generateFlatNormals(). If the mesh is not a triangle
     * mesh or doesn't have 3D positions, this flag does nothing. If the mesh
     * already has its own normals, these get replaced. If
     * @ref CompileFlag::GenerateSmoothNormals is specified together with this
     * flag, this flag gets a priority.
     */
    GenerateFlatNormals = 1 << 0,

    /**
     * If the mesh @ref MeshPrimitive::Triangles, generates normals using
     * @ref MeshTools::generateSmoothNormals() based on triangle adjacency
     * information from the index buffer. If the mesh is not indexed, this
     * behaves the same as @ref CompileFlag::GenerateFlatNormals. If the mesh
     * is not a triangle mesh or doesn't have 3D positions, this flag does
     * nothing. If the mesh already has its own normals, these get replaced.
     */
    GenerateSmoothNormals = 1 << 1
};

/**
@brief Mesh compilation flags
@m_since{2019,10}

@see @ref compile(const Trade::MeshData&, CompileFlags)
*/
typedef Containers::EnumSet<CompileFlag> CompileFlags;

CORRADE_ENUMSET_OPERATORS(CompileFlags)

/**
@brief Compile mesh data
@m_since_latest

Configures a mesh for a @ref Shaders::Generic shader with a vertex buffer and
possibly also an index buffer, if the mesh is indexed.

-   If the mesh contains positions, these are bound to the
    @ref Shaders::Generic2D::Position attribute if they are 2D or to
    @ref Shaders::Generic3D::Position if they are 3D.
-   If the mesh contains normals or if @ref CompileFlag::GenerateFlatNormals /
    @ref CompileFlag::GenerateSmoothNormals is set, these are bound to
    @ref Shaders::Generic3D::Normal.
-   If the mesh contains texture coordinates, these are bound to
    @ref Shaders::Generic::TextureCoordinates.
-   If the mesh contains colors, these are bound to
    @ref Shaders::Generic::Color3 / @ref Shaders::Generic::Color4 based on
    their type.

If normal generation is not requested, @ref Trade::MeshData::indexData() and
@ref Trade::MeshData::vertexData() are uploaded as-is without any further
modifications, keeping the original layout and vertex formats. If
@ref CompileFlag::GenerateSmoothNormals is requested, vertex data is
interleaved together with the generated normals; if
@ref CompileFlag::GenerateFlatNormals is requested, the mesh is first
deindexed and then the vertex data is interleaved together with the generated
normals.

The generated mesh owns the index and vertex buffers and there's no possibility
to access them afterwards. For alternative solutions see the
@ref compile(const Trade::MeshData&, GL::Buffer&, GL::Buffer&) overloads.

@note This function is available only if Magnum is compiled with
    @ref MAGNUM_TARGET_GL enabled (done by default). See @ref building-features
    for more information.

@see @ref shaders-generic
*/
MAGNUM_MESHTOOLS_EXPORT GL::Mesh compile(const Trade::MeshData& meshData, CompileFlags flags);

/**
 * @overload
 * @m_since_latest
 */
/* Separately because this one doesn't rely on duplicate() / interleave() /
   generate*Normals() and thus the exe can be smaller when using this function
   directly */
MAGNUM_MESHTOOLS_EXPORT GL::Mesh compile(const Trade::MeshData& meshData);

/**
@brief Compile mesh data using external buffers
@m_since_latest

Assumes the whole vertex / index data are already uploaded to @p indices /
@p vertices and sets up the mesh using those. Can be used to have a single
index/vertex buffer when multiple @ref Trade::MeshData instances share the same
data arrays, or to allow buffer access later. For example:

@snippet MagnumMeshTools-gl.cpp compile-external

Another use case is specifying additional vertex attributes that are not
recognized by the function itself. You can choose among various r-value
overloads depending on whether you want to have the index/vertex buffers owned
by the mesh or not:

@snippet MagnumMeshTools-gl.cpp compile-external-attributes

If @p meshData is not indexed, the @p indices parameter is ignored --- in that
case you can pass a @ref NoCreate "NoCreate"-d instance to avoid allocating an
unnecessary OpenGL buffer object.
*/
MAGNUM_MESHTOOLS_EXPORT GL::Mesh compile(const Trade::MeshData& meshData, GL::Buffer& indices, GL::Buffer& vertices);

/**
 * @overload
 * @m_since_latest
 */
MAGNUM_MESHTOOLS_EXPORT GL::Mesh compile(const Trade::MeshData& meshData, GL::Buffer& indices, GL::Buffer&& vertices);

/**
 * @overload
 * @m_since_latest
 */
MAGNUM_MESHTOOLS_EXPORT GL::Mesh compile(const Trade::MeshData& meshData, GL::Buffer&& indices, GL::Buffer& vertices);

/**
 * @overload
 * @m_since_latest
 */
MAGNUM_MESHTOOLS_EXPORT GL::Mesh compile(const Trade::MeshData& meshData, GL::Buffer&& indices, GL::Buffer&& vertices);

#ifdef MAGNUM_BUILD_DEPRECATED
/**
@brief Compile 2D mesh data
@m_deprecated_since_latest Use @ref compile(const Trade::MeshData&, CompileFlags)
    instead.

Configures a mesh for @ref Shaders::Generic2D shader with vertex buffer and
possibly also an index buffer, if the mesh is indexed. Positions are bound to
@ref Shaders::Generic2D::Position attribute. If the mesh contains texture
coordinates, these are bound to @ref Shaders::Generic2D::TextureCoordinates
attribute. If the mesh contains colors, these are bound to @ref Shaders::Generic3D::Color4
attribute. No data compression or index optimization (except for index buffer
packing) is done, both the vertex buffer and the index buffer (if any) is owned
by the mesh, both created with @ref GL::BufferUsage::StaticDraw.

This is just a convenience function for creating generic meshes, you might want
to use @ref interleave() and @ref compressIndices() functions together with
@ref GL::Mesh::setPrimitive(), @ref GL::Mesh::setCount(),
@ref GL::Mesh::addVertexBuffer(), @ref GL::Mesh::setIndexBuffer() instead for
greater flexibility.

@note This function is available only if Magnum is compiled with
    @ref MAGNUM_TARGET_GL enabled (done by default). See @ref building-features
    for more information.

@see @ref shaders-generic
*/
CORRADE_IGNORE_DEPRECATED_PUSH
CORRADE_DEPRECATED("use compile(const Trade::MeshData&) instead") MAGNUM_MESHTOOLS_EXPORT GL::Mesh compile(const Trade::MeshData2D& meshData);
CORRADE_IGNORE_DEPRECATED_POP

/** @brief Compile 2D mesh data
 * @m_deprecated_since{2018,10} Use @ref compile(const Trade::MeshData&)
 *      instead. The @p usage parameter is ignored and returned buffer
 *      instances are empty.
 */
CORRADE_IGNORE_DEPRECATED_PUSH
CORRADE_DEPRECATED("use compile(const Trade::MeshData&) instead") MAGNUM_MESHTOOLS_EXPORT std::tuple<GL::Mesh, std::unique_ptr<GL::Buffer>, std::unique_ptr<GL::Buffer>> compile(const Trade::MeshData2D& meshData, GL::BufferUsage usage);
CORRADE_IGNORE_DEPRECATED_POP

/**
@brief Compile 3D mesh data
@m_deprecated_since_latest Use @ref compile(const Trade::MeshData&, CompileFlags)
    instead.

Configures mesh for @ref Shaders::Generic3D shader with vertex buffer and
possibly also index buffer, if the mesh is indexed. Positions are bound to
@ref Shaders::Generic3D::Position attribute. If the mesh contains normals, they
are bound to @ref Shaders::Generic3D::Normal attribute, texture coordinates are
bound to @ref Shaders::Generic3D::TextureCoordinates attribute. If the mesh
contains colors, they are bound to @ref Shaders::Generic3D::Color4 attribute.
No data compression or index optimization (except for index buffer packing) is
done, both the vertex buffer and the index buffer (if any) is owned by the mesh,
both created with @ref GL::BufferUsage::StaticDraw.

This is just a convenience function for creating generic meshes, you might want
to use @ref interleave() and @ref compressIndices() functions together with
@ref GL::Mesh::setPrimitive(), @ref GL::Mesh::setCount(),
@ref GL::Mesh::addVertexBuffer(), @ref GL::Mesh::setIndexBuffer() instead for
greater flexibility.

@note This function is available only if Magnum is compiled with
    @ref MAGNUM_TARGET_GL enabled (done by default). See @ref building-features
    for more information.

@see @ref shaders-generic
*/
CORRADE_IGNORE_DEPRECATED_PUSH
CORRADE_DEPRECATED("use compile(const Trade::MeshData&, CompileFlags) instead") MAGNUM_MESHTOOLS_EXPORT GL::Mesh compile(const Trade::MeshData3D& meshData, CompileFlags flags = {});
CORRADE_IGNORE_DEPRECATED_POP

/** @brief Compile 3D mesh data
 * @m_deprecated_since{2018,10} Use @ref compile(const Trade::MeshData&, CompileFlags)
 *      instead. The @p usage parameter is ignored and returned buffer
 *      instances are empty.
 */
CORRADE_IGNORE_DEPRECATED_PUSH
CORRADE_DEPRECATED("use compile(const Trade::MeshData&) instead") MAGNUM_MESHTOOLS_EXPORT std::tuple<GL::Mesh, std::unique_ptr<GL::Buffer>, std::unique_ptr<GL::Buffer>> compile(const Trade::MeshData3D& meshData, GL::BufferUsage usage);
CORRADE_IGNORE_DEPRECATED_POP
#endif

}}
#else
#error this header is available only in the OpenGL build
#endif

#endif