sdf/sdf-base.lisp at master · lispgames/sdf · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
(in-package #:sdf/base)

;; metadata for an sdf render

(defclass sdf ()
  ;; includes bounding box and vector data for shape (coordinate
  ;; system is assumed to be Y-up)
  ((shape :initarg :shape :reader shape)
   ;; version of SHAPE with degenerate segments/curves, etc, removed
   (cleaned-shape :initarg :cleaned-shape :initform nil
                  :accessor %cleaned-shape)
   ;; version of CLEANED-SHAPE with overlapping contours combined
   (simplified-shape :initarg :simplified-shape :initform nil
                     :accessor %simplified-shape)
   ;; :sdf, :psdf, :msdf, :mtsdf, :smsdf, :smtsdf, etc
   (sdf-type :initarg :sdf-type :reader sdf-type)
   ;; 2d or 3d array of pixel values after sdf is generated. 0,0 is
   ;; lower left of SDF image
   (image :reader image :initform nil :initarg :image)
   ;; x or y coordinates of samples in image, as vector of real
   ;; (stored separately to make sure we always get same results in
   ;; various steps, and to allow calculating it with rationals to
   ;; reduce fp loss)
   (samples/x :reader samples/x :initform nil :initarg :samples/x)
   (samples/y :reader samples/y :initform nil :initarg :samples/y)

   ;; 2d bit array of flags indicating if a particular sample is
   ;; inside the shape (1 = in)
   (signs :Reader signs :initform nil :initarg :signs)
   ;; size of pixel of IMAGE in shape coordinate system
   (pixel-scale :reader pixel-scale :initform (v2 1 1) :initarg :pixel-scale)
   ;; position of origin of SHAPE coordinate system relative to center
   ;; of upper left pixel of IMAGE, in pixels
   (origin :initform (rv2 0 0) :reader origin :initarg :origin)
   ;; distance in pixels corresponding to a pixel value of 0 (=
   ;; maximum representable distance in distance field)
   (spread :initform 2.5 :reader spread :initarg :spread)
   ;; parameters for msdf variants
   (min-angle :initform (- pi 3) :initarg :min-angle :Reader min-angle)
   (min-sharp-edge-length :initform 0 :initarg :min-sharp-edge-length
                          :reader min-sharp-edge-length)))

(defmethod cleaned-shape ((sdf sdf))
  (or (%cleaned-shape sdf)
      (setf (%cleaned-shape sdf)
            (clean-shape (shape sdf)))))

(defmethod simplified-shape ((sdf sdf))
  (or (%simplified-shape sdf)
      (setf (%simplified-shape sdf)
            (simplify-shape (cleaned-shape sdf) :samples (samples/y sdf)))))