Paint - lab part

• Example application Screenshots
• Your task is to create a simple paint application using Windows Forms.
• In case of doubts, the application should be consistent with the functionality and appearance of the example application, but its potential errors should not be replicated.
• Tip: This app can be useful in the future for you if you implement it correctly.

Layout:

• Main window build of: Menu bar, Status bar, and image area.
• Image area displays the loaded image in its original size. When the image is bigger than the available space, the image is scrolled.
• Canvas has a 5 px margin.

App logic:

• Default image size: 800x600 px.
• Loading and saving images: bitmaps, PNGs and JPEGs.
• "Save As..." always opens a save dialog, and "Save" remembers the last filename.
• When the left mouse button is pressed, it draws over the image with a pen (default: black 1px width).
• "Edit colors..." - changing pen color (remembers last chosen color).
• Status bar displays mouse position over image (only on image) and its size.
• "New..." opens a dialog that allows for choosing a size (1-10000px) and background color. Width and height have values for the current image. Color is always white. Clicking on colors opens the color picker.

Hints:

• OpenFileDialog/SaveFileDialog
• Bitmap, PictureBox, Invalidate()
• AutoScroll, AutoScrollMinSize
• MouseMove, Graphics.FromImage
• FillRectangle, DrawLine

Points:

• Menu bar with proper keyboard shortcuts and access keys - 2 points
• Status bar - 1 point
• Open/Save dialogs with proper filters - 1 point
• Displaying loaded image - 2 points
• Working scroll area for large images - 2 points
• Drawing over an image with a pen - 2 points
• New canvas dialog - 2 points

Paint - home part

• Example application

• Implement your custom control for displaying images, allowing for canvas resizing with a mouse. Canvas has three handles, a proper cursor is displayed, and a dotted rectangle with a new size is visible when dragging.
• Implement operation on bitmap using direct access to the bitmap memory, see this post - this allows for fast operation on a bitmap.
• Invert colors should work almost instantly, like in the example app.
• Selection part of the canvas with a mouse. The status bar displays information about it. During selection, the rectangle is dashed black. After that, the color changes to blue. Working "Select All" in the menu.
• Add custom events for notifying the main window about mouse movement, selection changing, and zooming.
• Create an abstract class for tools and implement PenTool, SelectionTool, and LineTool.
• Application remembers 10 recently opened files and displays them in the File menu. Use INI files to store them.
• Create a custom control for a color palette. It allows for adjusting all colors and quickly picking them later.

Points:

• Custom canvas control + canvas resizing - 2 points
• Selection - 2 points
• Zooming - 2 points
• Tools (with proper abstraction): Pen, Selection, Line - 1 point each (3 points in total)
• Image invert (quick) - 1 point
• Storing a list of recently open/saved files - 1 point
• Color palette control - 1 point