#hline

1fn hline(inout self, y: float, h: float)

The hline function draws a horizontal line within the Sdf2d drawing context at a specified y-coordinate and with a specified half-thickness. This function is useful for adding horizontal lines or dividers in your graphics or UI elements.

#Parameters

• self (inout): A reference to the Sdf2d instance. The function modifies the internal state of self to include the horizontal line shape.
• y (float): The y-coordinate of the center of the horizontal line.
• h (float): The half-thickness of the line. The total thickness of the line will be 2 * h.

#Returns

• void: This function does not return a value but updates the internal state of self to represent the horizontal line.

#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 a horizontal line at y = 50.0 with half-thickness 2.0.
6    sdf.hline(50.0, 2.0);
7
8    // Fill the horizontal line with a solid red color.
9    sdf.fill(#f00);
10
11    // Rotate the drawing by 90 degrees (PI * 0.5 radians) around point (50.0, 50.0).
12    sdf.rotate(PI * 0.5, 50.0, 50.0);
13
14    // Return the final color result.
15    return sdf.result;
16}

#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 Horizontal Line: Use sdf.hline to draw a horizontal line centered at y = 50.0 with a half-thickness of 2.0. This results in a line that is 4.0 units thick.
• Apply Fill: Fill the horizontal line with red color using sdf.fill(#f00). The color #f00 is shorthand for red in hexadecimal notation.
• Rotate Drawing: Rotate the entire drawing context by 90 degrees (PI * 0.5 radians) around the point (50.0, 50.0). This demonstrates how transformations can be applied to the drawing.
• Return Result: Return sdf.result, which contains the final rendered color after all drawing operations.

#Notes

• Thickness Control: Adjusting the h parameter changes the thickness of the line. A larger h results in a thicker line.
• Positioning: The line spans horizontally across the drawing area at the specified y coordinate.
• Transformations: Additional transformations like translate, rotate, or scale can be applied to the Sdf2d context to manipulate the position and orientation of the line.
• Drawing Order: Ensure that you call a fill function like fill or fill_keep after defining the shape to render it.e