Collaging

Overview

• Controller: CollageController
• Model: CollageModel
• View: TextView

Controller

The controller CollageController has three behaviors for its interface. The implementation has a Readable in, TextView, CollageModel as its field and its constructor takes in these parameters. The purpose of this controller is to take in the user input and parse information from this controller to both the view and the model.

runCollage()

This function runs the overall controller and loops until the user quits. It takes in a line from the command text and executes the command. The scanner would separate the arguments and parse it into the runCommand() with the arguments.

runCommand(String command, String... args)

This function is given a command and the arguments and executes the command. The options for the commands:

1. quit: Quits the controller.
2. new-project: Creates a new project with the given height and width.
3. load-project: Load the given project file name
4. save-project: Save the project with the given file path.
5. add-layer: Adds a layer with the given name to the project.
6. add-image-to-layer: Adds the given image file path to the given layer name with the given position.
7. save-image: Saves the image as a .ppm file with the given name.
8. set-filter: Set the filter of the given layer name with the given filter option.

printMessage(String message)

This function appends the given message to the view of the controller. If the view throws an "IOException", then the function will simply print in the System.out console " Failure in transmitting custom message!".

Model

The model CollagePPM implements an interface called CollageModel and takes in the behaviors. The model has four fields and its constructor takes in three values: height, width, and maxValue The last field is a List<Layer> and this will represent the layers in a image processor.

The following behaviors are the methods for the CollageModel

addImageToLayer(Layer layer, IListOfPixel img, int row, int col)

The addImageToLayer takes in a layer, an IListOfPixel object (which can be a Layer or an Image), a row, and a column. The return type is void since it just modifies the given layer. It takes the matrix of the IListOfPixel object and adds it to the given layer with the coordinates.

addLayer(String layer)

This function just creates a new layer with the given Laye name. The function may throw an IllegalArgumentException when the layer name already exists in the model.

saveImage()

This function first combines all the Layers together and combines into one Layer. It returns the combined layer and this function will be fed into a FileWriter to be written as a PPM file.

renderLayers()

This function also combines all the layers together and adds it to a list of Layers. The layer's order would go from bottom-most layer to the top-most layer. This means the first layer in the list would be the bottom-most layer in the model.

ppmFormat()

This function returns a string format that resembles a PPM file. However, it also includes all the layer's information including name and filter name and the content. The format should look like this:

C1
width height
max-value
layer-name filter-name
LAYER-CONTENT-FORMAT
...
layer-name filter-name
LAYER-CONTENT-FORMAT
...

Getters

The getters and setters are only for the fields. These are important for parsing information into other classes. This can help with the height, width, and max value of a layer so that there wouldn't be any errors on out-of-bounds errors.

Design Changes and New Additions

PLEASE REFER TO THE NEW CLASS DIAGRAM PROVIDED IN THE RES FOLDER.

Controller Package

• CollageControllerImpl class: added a new method printCommands() that prints the command line options/arguments a user can use when running the controller.

• CollageFeatures Interface: a new interface with a command callback design pattern that establishes communication between the Controller and the View.

• CollageGUI class: a new class that implements the CollageController and CollageFeatures interfaces that implements a controller for the GUI.

Model Package

• CollageModel Interface: added a startModel(int height, int width, int maxValue) method that launches a new project with the given parameters, a removeLayer(String name) method that removes the given Layer (its name) from the working project; overloaded the toString() method to have a string representation of the project.

• CollagePPM class: implemented the new methods from the interface above, fixed a NullPointerException bug in the addLayer(String layer) method, fixed object reference copy issue in the setFilter((String layer, Filter option) method (getter returned a copy of layer and modification were not being made to the actual layer in the project).

• Filter Class : redesigned class to be an enum as it was a better data representation since we have a limited set of filters to work with.

• IPixel interface: an interface that represents the general behavior of pixels, extendable for future revisions or design additions. It includes all public methods previously declared in the Pixel class in addition to a new invert(IPixel prev) method that inverts the colors of a pixel.

• IListPixel interface: Removed convertToMatrix() method, we thought it fit better in a utility class.

• Pixel class: modified the brighten(IPixel prev) and darken(Ipixel prev) methods to work with the HSL pixel representation, implemented the invert(IPixel prev) method.

• Posn class: added some missing Javadoc.

View Package

• GUIView interface: a new interface that defines the behavior of our GUI for collaging.

• CommandListPanel class: a new class that extends JPanel and implements the command buttons for our GUI.

• DisplayPanel class: a new class that also extends JPanel and implements the displaying of the image in the GUI throughout the collaging process.

• WelcomeDialog class: a new class that extends JDialog and displays the welcome message for our GUI, allowing users to initially either create a new project or to load an existing one.

Support for JPEG and PNG Images (A6)

To implement support for JPEG and PNG images in our Collaging app, we added three new methods in the ImageUtilClass:

• readimages(String filename): a method that reads the given file name (acceptable file extensions include: .ppm, .jpeg and .png) and returns a list of pixels representing the image.
• writeImage(IlistOfPixel img, String filename): a method that takes in an image in the form of a list of pixels and an image file name (same file extension support as method above) and writes the list of pixels to the image with the given filename.
• createImageObject(IlistOfPixel img): a method that creates a rendered image from the given list of pixels.

Decoupling changes

We decoupled our MVC as much as possible without having to completely change our design, only the following files are needed for the views to compile:

• CollageFeatures.java interface: required for the GUI to communicate with the controller and make the required modification and method calls to the model.
• CollageModel.java interface: required for the view to know the current state of the collaging project.
• IFilter.java interface: required for the model interface to be able to set filters on the images being processed.
• IListOfPixel: required for the model to manipulate layers to either remove them or add images to them.
• IPixel.java interface: required for the model to manipulate the individual pixels in the images or layers.
• Pixel.java class: required for the utility classes when reading and writing to image files.
• IPosn.java interface: required for the model to position individual pixels in the images.
• Posn.java class: required for the utility classes when making two-dimensional arrays of pixels.
• ImageUtil.java class:

Images and examples

All example images (including a screenshot of the GUI with a loaded image) and the class diagram can be found in the res/ folder.

Image Citations

https://www.neighbourly.co.nz/public/auckland/point-chevalier/message/58623691 https://secure.gravatar.com/avatar/d67e563d5e66ccd7170ba9f631bb5757?s=256&d=mm&r=g