OrbitEngine::Graphics::Atlas class
#include <OE/Graphics/Atlas.hpp>

Generic 2D atlas class.

Contents

For examples see BitmapAtlas and TextureAtlas

Metadata format:

{
    "frames": [
        {
            "i": 1, // frame index
            "x": 0,
            "y": 0,
            "w": 64,
            "h": 64,
            "f": false // flipped?
        },
        ...
    ],
    "animations": [
        // TODO...
    ]
}

Derived classes

template<typename T, unsigned int N = 1>
class BitmapAtlas
A 2D bitmap atlas.
class TextureAtlas
A 2D texture atlas.

Public types

struct Frame
Holds the information to locate a frame.
struct FrameMetadata
Holds additional information of a frame.

Constructors, destructors, conversion operators

Atlas() protected
~Atlas() protected virtual

Public functions

auto getTexelSize() const -> Math::Vec2f pure virtual
Returns texel sizes in both dimensions (1.0f / size)
auto hasFrame(FrameIndex index) const -> bool
Returns whether the provided index already exists.
auto getFrame(FrameIndex index) const -> const Frame&
Get a constant reference of a frame.

Protected functions

void writeMetadata(Misc::JSONWriter& writer) const
Generates JSON metadata.
void loadMetadata(const rapidjson::Value& data)
Load JSON metadata.
auto exportToFile(const std::string& metadata) const -> bool
Exports the metadata to the disk.
auto addFrame(FrameIndex index, int x, int y, int w, int h, bool flipped, FrameMetadata meta) -> bool
Add a frame's metadata to the atlas.

Function documentation

const Frame& OrbitEngine::Graphics::Atlas::getFrame(FrameIndex index) const

Get a constant reference of a frame.

Parameters
index in requested frame index

bool OrbitEngine::Graphics::Atlas::addFrame(FrameIndex index, int x, int y, int w, int h, bool flipped, FrameMetadata meta) protected

Add a frame's metadata to the atlas.

Parameters
index in identifier within the atlas, must be unique
x in location of the frame
y in location of the frame
w in sizes of the frame
h in sizes of the frame
flipped in if the provided frame is rotated 90 degrees clockwise
meta in additional metadata
Returns Whether the operation was successful