Undo Redo module

The undo/redo module provides support for undo/redo operations

Enabling the module

To enable the plotting module, you can either hardcode the USE_UNDO_MODULE option in your CMakeLists.txt file by finding the following line:

option(USE_UNDO_MODULE "Use the undo module" OFF)

and modifying the line to look like this

option(USE_UNDO_MODULE "Use the undo module" ON)

Alternatively, you can also generate your project files using CMake options by running the following CMake command:

cmake .. -DCMAKE_BUILD_TYPE=RELEASE -DUSE_UNDO_MODULE=ON

Finally, update your uvproj.yaml so that the undo-redo key under enabled-modules is set to true like this:

name: "MyProject"
version: "1.0.0.0"
engine-version: "1.0.0.0"
enabled-modules:
  undo-redo: true

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Next, in your source file, include the Modules.hpp header in your components like this:

#include <Modules/Modules.hpp>

Event safety

The entire module is flagged as event safe at Post-begin

Using the Undo/Redo module

The module stores data in the Transaction data type, as can be seen below:

struct UIMGUI_PUBLIC_API Transaction
{
    std::function<void(TransactionPayload&)> undofunc;
    std::function<void(TransactionPayload&)> redofunc;
    TransactionPayload payload;
};

The 2 functions are the events to be called on undo and redo respectively

The payload member is of type TransactionPayload which is a simple struct storing a void* for a buffer and its size like this:

struct UIMGUI_PUBLIC_API TransactionPayload
{
    void* payload;
    size_t size;
};

So to push a transaction create a transaction, initialize the events and the payload and push it as an argument to the push function like this

Transaction transaction = 
{
    .undofunc = [](TransactionPayload&){ Logger::log("Undo", UVKLog::UVK_LOG_TYPE_NOTE); },
    .redofunc = [](TransactionPayload&){ Logger::log("Redo", UVKLog::UVK_LOG_TYPE_NOTE); },
    .payload = 
    { 
        .payload = nullptr,
        .size = 0,
    }
};

UImGui::StateTracker::push(transaction);

and now you have added an action that can be undone.

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To undo or redo an action, simply call the undo or redo member functions of the StateTracker class like this

UImGui::StateTracker::undo();
UImGui::StateTracker::redo();

and you should get the appropriate output logged to the console