#line_to

1fn line_to(inout self, x: float, y: float)

The line_to function draws a line segment from the current position (self.last_pos) to a specified point (x, y). This updates the path in the Sdf2d drawing context, allowing you to create complex shapes by connecting multiple points.

#Parameters

• self (inout): A reference to the Sdf2d instance. The function modifies internal fields (dist, shape, old_shape, clip, has_clip, last_pos) to reflect the new line segment.
• x (float): The x-coordinate of the line's endpoint.
• y (float): The y-coordinate of the line's endpoint.

#Returns

• void: This function does not return a value but updates the internal state of self to include the new line segment in the current path.

#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    // Start a new path at point (30.0, 30.0).
6    sdf.move_to(30.0, 30.0);
7
8    // Draw lines to create a star shape.
9    sdf.line_to(50.0, 70.0);   // Line to point (50.0, 70.0).
10    sdf.line_to(70.0, 30.0);   // Line to point (70.0, 30.0).
11    sdf.line_to(10.0, 50.0);   // Line to point (10.0, 50.0).
12    sdf.line_to(90.0, 50.0);   // Line to point (90.0, 50.0).
13
14    // Close the path to complete the shape.
15    sdf.close_path();
16
17    // Fill the shape with a solid red color.
18    sdf.fill(#f00);
19
20    // Return the final color result.
21    return sdf.result;
22}

#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.

• Start Path: Set the starting point of the path at (30.0, 30.0) using sdf.move_to.

• Draw Lines: Use sdf.line_to to draw lines connecting to various points, constructing the outline of a star shape.

• Close Path: Use sdf.close_path to draw a line back to the starting point, ensuring that the shape is closed.

• Apply Fill: Fill the closed path with red color using sdf.fill(#f00).

• Return Result: Return sdf.result, which contains the final rendered color after all drawing operations.

#Notes

• Path Construction: The combination of move_to, line_to, and close_path allows you to create complex vector shapes by defining their outlines point by point.

• State Management: Each call to line_to updates the current position (self.last_pos). The close_path function uses this position to connect back to the starting point (self.start_pos).

• Drawing Order: Ensure that you define your entire path and close it before applying fills or strokes to render the shape correctly.

• Transformations: You can apply transformations like translate, rotate, or scale to the Sdf2d context to manipulate the shape as needed.