#arc2

1fn arc2(inout self, x: float, y: float, r: float, s: float, e: float)

The arc2 function draws an arc segment of a circle within the Sdf2d drawing context. It defines a portion of a circle centered at (x, y) with radius r, starting from angle s and ending at angle e. The arc is shaped based on the current position within the drawing context.

#Parameters

• self (inout): A reference to the Sdf2d instance. The function modifies the internal state of self to represent the arc shape.
• x (float): The x-coordinate of the circle's center.
• y (float): The y-coordinate of the circle's center.
• r (float): The radius of the circle.
• s (float): The start angle of the arc in radians. Angles are measured from the positive x-axis.
• e (float): The end angle of the arc in radians.

#Returns

• This function does not return a value but updates the internal shape within the Sdf2d context to include the arc.

#Example

1fn pixel(self) -> vec4 {
2    // Create an Sdf2d drawing context for the current viewport.
3    let sdf = Sdf2d::viewport(self.pos * self.rect_size);
4    
5    // Draw an arc centered at (50.0, 50.0) with a radius of 40.0,
6    // starting from 0 radians (0 degrees) to PI radians (180 degrees).
7    sdf.arc2(50.0, 50.0, 40.0, 0.0, PI);
8    
9    // Apply a solid red fill to the arc.
10    sdf.fill(#f00);
11    
12    // Return the final color result.
13    return sdf.result;
14}

#Explanation

In this example:

• Create Drawing Context: Initialize the Sdf2d context using the current position (self.pos) and size (self.rect_size) of the viewport.
• Draw Arc: Use arc2 to draw a semicircular arc centered at (50.0, 50.0) with a radius of 40.0. The arc starts from 0.0 radians (corresponding to the positive x-axis) and ends at PI radians (180 degrees), forming the upper half of a circle.
• Apply Fill: Call fill with the color #f00 (solid red) to fill the arc shape.
• Return Result: Return sdf.result, which contains the final rendered color.

#Notes

• Angle Measurements: Angles s and e are measured in radians. A full circle is 2 * PI radians. Use PI / 2 for 90 degrees, PI for 180 degrees, etc.
• Drawing Order: The arc2 function modifies the shape used by the fill functions. Ensure you call fill, fill_keep, or another drawing function after defining the arc to render it.
• Transformations: You can apply transformations like translate, rotate, or scale before drawing the arc to position and orient it as needed.