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TFTShape is an extension to draw shape-based objects on screen. The target of this extension is to abstract low level primitives but with full use of the TFT_eSPI core functions (no setPixel operations). Shapes are graphical objects with the most common 2D functionality such as draw, fill, scale and rotate. Shapes consists of vertices which will be interpteted by the TFTShape class to form points, lines, polygons etc. Vertices can be user defined or they can be generated by various TFTShape builder functions. To give you an overview, here is a short example to see how to use this extension: TFTShape is an extension to draw shape-based objects on screen. The target of this extension is to abstract low level primitives but with full use of the TFT_eSPI core functions (no setPixel operations). Shapes are graphical objects with the most common 2D functionality such as draw, fill, scale and rotate. Shapes consists of vertices which will be interpteted by the TFTShape class to form points, lines, polygons etc. Vertices can be user defined or they can be generated by various TFTShape builder functions. To give you an overview, here is a short example to see how to use this extension:
##Building an analog clock ##Building an analog clock
### clock-face ### clock-face
To draw a clock face, only three lines of code will be needed. The basic idea is to define a 12-sided grid and draw a small dot on the corners of the grid. Fortunately TFTShape has the functionality not only to draw the shape itself but it can take also an argument to draw another shape (at all vertices positions). So the code is very simple: create a shape used for the 5 minutes dots, create a shape for an invisible grid and finally draw this grid with a Shape as an argument: To draw a clock face, only three lines of code will be needed. The basic idea is to define a 12-sided polygon and draw a small dot on the vertices of the polygon. Fortunately TFTShape has the functionality not only to draw the shape itself but it can take also an argument to draw another shape (at all vertices positions). So the code is very simple: create a shape used for the 5 minutes dots, create a shape for an invisible grid and finally draw this grid with a Shape as an argument:
```javascript ```javascript
TFTShape dot=TFTShape::buildNgon(8,6); TFTShape dot=TFTShape::buildNgon(8,6); //generate an Oktogon with radius of 6
TFTShape grid5minutes=TFTShape::buildNgon(12,100); TFTShape grid5minutes=TFTShape::buildNgon(12,100); //generate a Dodekagon with radius of 100
grid5minutes.fill(&tft2,120,160,dot,TFT_GREY); grid5minutes.fill(&tft,120,160,dot,TFT_GREY); //place grid at 120/160 and draw/fill all vertices with the dot-shape
``` ```
And this is the result: Note: filling functions using the fastDrawXXX functions of the TFT_eSPI Api.
And this is the result of this code:
![clock-face](images/screenshot_4571.png) ![clock-face](images/screenshot_4571.png)
### hands
To draw a realistic clock hand, which should not be a single line and the anchor should not be exactly on one end of the hand, we design here a pentagon and scale this in one direction to our needs. Furthermore, because all of the TFTShape builder functions generate symmetrical shapes with the anchor point at the center, we need to move this anchor point (pivot point) nearly to the end of the hand.