Programming C++Builder How to Use Common Properties and Methods of TCanvas in CBuilder or Delphi?

How to use common properties and methods of Canvas?

The following table lists the commonly used properties of the Canvas object in C++Builder and Delphi.

Properties Descriptions
Font Specifies the font to use when writing text on the image. Set the properties of the TFont object to specify the font face, color, size, and style of the font.
Brush Determines the color and pattern the canvas uses for filling graphical shapes and backgrounds. Set the properties of the TBrush object to specify the color and pattern or bitmap to use when filling in spaces on the canvas.
Pen Specifies the kind of pen the canvas uses for drawing lines and outlining shapes. Set the properties of the TPen object to specify the color, style, width, and mode of the pen.
PenPos  Specifies the current drawing position of the pen. 
Pixels Specifies the color of the area of pixels within the current ClipRect. 

These properties are described in more detail in Using the properties of the Canvas object.
 

Here is a list of several methods of TCanvas component you can use:

Method Descriptions
Arc Draws an arc on the image along the perimeter of the ellipse bounded by the specified rectangle. 
Chord Draws a closed figure represented by the intersection of a line and an ellipse.
CopyRect Copies part of an image from another canvas into the canvas. 
Draw Renders the graphic object specified by the Graphic parameter on the canvas at the location given by the coordinates (X, Y).
Ellipse Draws the ellipse defined by a bounding rectangle on the canvas. 
FillRect Fills the specified rectangle on the canvas using the current brush.
FloodFill (VCL only) Fills an area of the canvas using the current brush. 
FrameRect  Draws a rectangle using the Brush of the canvas to draw the border.
LineTo  Draws a line on the canvas from PenPos to the point specified by X and Y, and sets the pen position to (X, Y).
MoveTo  Changes the current drawing position to the point (X,Y). 
Pie  Draws a pie-shaped the section of the ellipse bounded by the rectangle (X1, Y1) and (X2, Y2) on the canvas. 
Polygon Draws a series of lines on the canvas connecting the points passed in and closing the shape by drawing a line from the last point to the first point.
Polyline  Draws a series of lines on the canvas with the current pen, connecting each of the points passed to it in Points.
Rectangle  Draws a rectangle on the canvas with its upper left corner at the point (X1, Y1) and its lower right corner at the point (X2, Y2). Use Rectangle to draw a box using Pen and fill it using Brush.
RoundRect  Draws a rectangle with rounded corners on the canvas. 
StretchDraw Draws a graphic on the canvas so that the image fits in the specified rectangle. The graphic image may need to change its magnitude or aspect ratio to fit.
TextHeight, TextWidth Returns the height and width, respectively, of a string in the current font. Height includes leading between lines.
TextOut  Writes a string on the canvas, starting at the point (X,Y), and then updates the PenPos to the end of the string.
TextRect  Writes a string inside a region; any portions of the string that fall outside the region do not appear. 

These methods are described in more detail in Using Canvas methods to draw graphic objects.


Add comment


Security code
Refresh

Programming - C++Builder