Tutorials » Rendering » How to render 2D Images

The Untold Engine supports the rendering of 2D images. The engine refers a 2D image as a U4DEngine::U4DImage object.

Rendering a 2D image

To render a 2D image, you first instantiate a U4DEngine::U4DImage object as shown in line 1.

Note: Please make sure to read the Untold Engine Toolchain before continuing on with this tutorial. All images must be converted to binary format (.u4d) using the Digital Asset Converter.

Next, provide the name of the image you want to render and the desired dimension for the image (line 2). In this case, I want to render an image called "spaceinvader.png".

The image object is then added to the scenegraph (line 3).

Finally, the image is translated 0.5 units up and to the left (line 4). Recall that the coordinate system for 2D objects is different than for 3D objects. For 2D objects, the coordinate system ranges between [-1.0,1.0].

//The resource loader singleton will load all binary data into the engine
U4DEngine::U4DResourceLoader *resourceLoader=U4DEngine::U4DResourceLoader::sharedInstance();

//The .u4d file should contain the binary representation of your image. Please read about the Untold Engine Toolchain
resourceLoader->loadTextureData("uiTextures.u4d");

//Line 1. Create an instance of U4DImage
U4DEngine::U4DImage *myImage=new U4DEngine::U4DImage();

//Line 2. Set the image to use and the desired width and height
myImage->setImage("spaceinvader.png",100,75);

//Line3. Add the image to the scenegraph. Since the demo has a skybox, I'm setting the z-depth to -2
addChild(myImage,-2);

//Line 4. Translate the image
myImage->translateBy(0.5,0.5,0.0);

Here is an example of the result:

Image

Tips

  • To properly render an image, the 2D image needs to be flipped vertically as shown below. In this instance, I use Gimp to flip the .png file vertically.
Image