![end screen annotation problems end screen annotation problems](https://socialmediaweek.org/wp-content/blogs.dir/1/files/yt-end-screen.jpg)
If over RotateRect set the position and flags for rotating.If it is, check if it is over one of the editing hotspots.Mouse DownĬhecks if the pointer is over the currently selected gAnnotater, set the position and flags for moving. The mouse events handle the panning of the image, and the moving, re-sizing, and rotating of the gAnnotaters. This is useful for panning and zooming where re-building is not necessary. Like the gAnnotater, the gCanvas has an image property to store the completely assembled image in. Even these scrollbars have their own quirks, but this could be worked around.
End screen annotation problems plus#
The control surface plus one Horizontal ScrollBar and one Vertical ScrollBar. After playing with different ideas, I realized I would have to make this a custom control. When you are done, the Assembled Image can be exported as one image or saved as a project to be re-loaded and edited later.Īt first, I thought I could just use a Panel and use the built in ScrollBars, but there is a strange "bug?" that causes the scrollbars to reset to zero with focus changes. Now that you have an image loaded, add as many gAnnotaters as needed and change the appearance to suit your needs. If the image is bigger than the gCanvas, it can be panned or zoomed. The gCanvas has an Image Property to hold the image to be annotated. The gCanvas is a control that can be dropped on a Form and do just that. Now we need a way to display it, add it to an image, and interact with it. The gAnnotater is only a class that builds the image. When the gAnnotater is Selected, a Selection Rectangle is drawn to highlight the areas of mouse interaction. Rather than re-building the control every time it is painted, I store an image of the gAnnotater so it can be painted immediately if no re-building is necessary. More details on Rotation will be in the gCanvas section. Just be sure to get the new centerpoint before rotating back. So I simply un-rotate, re-size based on the (X,Y) Deltas, and rotate back. After failing to come up with some brilliant way to easily calculate this, I realized re-sizing was really the same no matter what the rotation is if you look at it with the surface rotated too. The tricky part was re-sizing a rotated rectangle. To re-size the control, just re-construct the Rect with new dimensions using the mouse position returned by the gCanvas and the Rect.Location. ' Rotate the points for the mouse trapping PtsResizeRectVert = RectToPoints(ResizeRectVert) PtsResizeRectHorz = RectToPoints(ResizeRectHorz) Each Rectangle needs to be converted with the RectToPoints function. A Matrix cannot rotate a Rectangle directly, but it can rotate a Point Array. To do this, create a Matrix and pass the angle and pivot point with the RotateAt function. A Graphics Matrix is used to rotate the gAnnotater. The rotation and re-sizing of the control is based on information about the mouse position that is coming from the gCanvas. Their use will be explained in more detail later in the gCanvas section. ResizeRect, ResizeRectVert, and ResizeRectHorz are used for re-sizing the control with the mouse. RotateRect is the small square in the upper right corner used for rotating the control with the mouse.
![end screen annotation problems end screen annotation problems](https://r-graphics.org/R-Graphics-Cookbook-2e_files/figure-html/FIG-ANNOTATE-TEXT-1.png)
Get or Set the Rotational angle of the controlĮach RectangleF identifies each area of the gAnnotater. Handle the appearance of the Border around the Control BorderType, BorderColor, BorderWidth, BorderLine.Set the Background to a color or Image and the transparency BackColor, BackOpacity, BackgroundImage.TextOutline, TextOutlineColor, TextOutlineOpacityĪll adjust the Outline Width, Color and Transparency around the Text.Here is a list of the primary properties:Īll adjust the Text string's value, Color and transparency The appearance can be changed with the many properties. The gAnnotater is a rectangular object that draws an image of the gAnnotater on a Graphics Object. These can be used with the gAnnotation as in the "Complex" demo here or use them by themselves in another project. There are also WinForms versions of each if you need to put them directly on a Form or Dialog. There is also a bonus gFontToolStripControls library with custom ToolStrip controls for Fonts, Colors, and Ranged Value Adjustment aka Slider. The last is the gCanvasData that allows the Project to be serialized for saving. Each gAnnotater object can be re-sized and rotated by dragging the handles with the mouse. The gAnnotater class is the object that can be added to the gCanvas and manipulated directly on the screen. It also allows the image to be panned and zoomed.
![end screen annotation problems end screen annotation problems](https://i1.rgstatic.net/publication/260326152_The_collaborative_lecture_annotation_system_CLAS_A_new_TOOL_for_distributed_learning/links/550a7ca20cf20f127f91cf3b/largepreview.png)
The gCanvas holds and displays the image and gAnnotater collection. There are three components to the library: gAnnotater, gCanvas, and gCanvasData.
![end screen annotation problems end screen annotation problems](https://cdn.24htech.asia/link/wp-content/uploads/2021/12/10050954/image-7-of-the-best-google-chrome-extensions-to-annotate-text-on-the-web-163906259480319.jpg)
The gAnnotation is a control library that allows text to be added to an image for annotation or watermarking.