Cinder Creative Coding Cookbook: If you know C++ this book takes your creative potential to a whole other level. The practical recipes show you how to create interactive and visually dynamic applications using Cinder which will excite and delight your audience.

In this chapter, we will introduce several simple recipes that can be very useful during the development process.

Graphical User Interface (GUI) is often required for controlling and tuning your Cinder application. In many cases, you spend more time tweaking the application parameters to achieve the desired result than writing the code. It is true especially when you are working on some generative graphics.

Cinder provides a convenient and easy-to-use GUI via the InterfaceGl class.

#include "cinder/params/Params.h"

Many applications that you will develop operate on input parameters set by the user. For example, it could be the color or position of some graphical elements or parameters used to set up communication with other applications. Reading configurations from external files is necessary for your applications. We will use a built-in Cinder support for reading and writing XML files to implement the configuration persistence mechanism.

string mHostIP;
int mHostPort;

We will implement a simple but useful mechanism for saving and loading the parameters' states. The code used in the examples will be based on the previous recipes.

ColorA mColor;

We are going to add to your 3D scene a navigation facility known to us since we modelled a 3D software. Using MayaCamUI, you can do this with just a few lines of code.

Getting ready

We need to have some 3D objects in our scene. You can use some primitives provided by Cinder, for example:

gl::drawColorCube(Vec3f::zero(), Vec3f(4.f, 4.f, 4.f));

A color cube is a cube with a different color on each face, so it is easy to determine the orientation.

We will try to use built-in Cinder methods to visualize some basic information about the scene we are working on. It should make working with 3D space more comfortable.

We will implement an example communication between two Cinder applications written in Cinder to illustrate how we can send and receive signals. Each of these two applications can be replaced by a non-Cinder application very easily.

We are going to use the Open Sound Control (OSC) messaging format, which is dedicated for communication between wide ranges of multimedia devices over the network. OSC uses UDP protocol, providing flexibility and performance. Each message consists of URL-like addresses and arguments of integer, float, or string type. The popularity of OSC makes it a great tool for connecting different environments or applications developed with different technologies over the network or even on the local machine.

We have implemented the sender application that sends the position of the mouse via OSC protocol. Those messages, with the address /obj/position, can be received by any non-Cinder OSC application implemented in many other frameworks and programming languages. The first argument in the message is the x axis position of the mouse and the second argument is the y axis position. Both are of the float type.

In our case, the application that receives messages is another Cinder application that draws a filled circle at exactly the same position where you point it in the sender application window.

That was just a short example of the possibilities that OSC offers. This simple communication method can be applied even in very complex projects. OSC works great when several devices are working as independent units. But at some point, data coming from them is processed; for example, frames coming from the camera can be processed by the computer vision software and results sent over the network to another machine projecting the visualization. Implementation on top of the UDP protocol gives not only performance, because of the fact that transmitting data is faster than using TCP, but also implementation is much simpler without a connection handshake.

You can find more information about OSC implementations by checking out the following links.

The big benefit of using Cinder is the resulting multiplatform code. In most cases, your application can be compiled on Windows, Mac OS X, and iOS without significant modifications.