tinmop/src/2d-utils.lisp

;; tinmop: an humble gemini and pleroma client
;; Copyright (C) 2022  cage

;; This program is free software: you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation, either version 3 of the License, or
;; (at your option) any later version.

;; This program is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with this program.  If not, see <http://www.gnu.org/licenses/>.

(in-package :2d-utils)

(eval-when (:compile-toplevel :load-toplevel :execute)
  (deftype ivec4-type ()
    '(signed-byte 32))

  (deftype ivec4 ()
    "A 4d vector of unsigned integer."
    `(simple-array ivec4-type (4)))

  (defun ivec4p (a)
    (typep a 'ivec4))

  (defun ivec4= (a b)
    (every #'= a b)))

(defun ivec4 (x y z &optional (w 0))
  (let ((res (misc:make-array-frame 4 0 'ivec4-type t)))
    (setf (elt res 0) x
          (elt res 1) y
          (elt res 2) z
          (elt res 3) w)
    res))

(defun copy-ivec4 (old)
  (let ((res (misc:make-array-frame 4 0 'ivec4-type t)))
    (declare (ivec4 res))
    (setf (elt res 0) (elt old 0)
          (elt res 1) (elt old 1)
          (elt res 2) (elt old 2)
          (elt res 3) (elt old 3))
    res))

(defun make-fresh-ivec4 ()
  (misc:make-array-frame 4 0 'ivec4-type t))

(defun iaabb2-min-x (aabb)
  (declare (ivec4 aabb))
  (declare (optimize (speed 3) (debug 0)))
  (elt aabb 0))

(defun iaabb2-max-x (aabb)
  (declare (ivec4 aabb))
  (declare (optimize (speed 3) (debug 0)))
  (elt aabb 2))

(defun iaabb2-min-y (aabb)
  (declare (ivec4 aabb))
  (declare (optimize (speed 3) (debug 0)))
  (elt aabb 1))

(defun iaabb2-max-y (aabb)
  (declare (ivec4 aabb))
  (declare (optimize (speed 3) (debug 0)))
  (elt aabb 3))

(defun make-iaabb2 (min-x min-y max-x max-y)
  (declare (optimize (speed 3) (debug 0)))
  (ivec4 min-x min-y max-x max-y))

(defun iaabb2~ (a b)
  (declare (ivec4 a b))
  (declare (optimize (speed 3) (debug 0)))
  (and (= (elt a 0) (elt b 0))
       (= (elt a 1) (elt b 1))
       (= (elt a 2) (elt b 2))
       (= (elt a 3) (elt b 3))))

(defun valid-iaabb2 (aabb)
  (declare (ivec4 aabb))
  (declare (optimize (speed 3) (debug 0)))
  (and (>= (elt aabb 0) 0)
       (>= (elt aabb 1) 0)
       (>= (elt aabb 2) 0)
       (>= (elt aabb 3) 0)
       (>  (elt aabb 2) (elt aabb 0))
       (>  (elt aabb 3) (elt aabb 1))))

(defun expand-iaabb2 (aabb coord)
  (let ((cp (copy-ivec4 aabb)))
    (when (< (elt coord 0) (elt aabb 0))
      (setf (elt cp 0) (elt coord 0)))
    (when (> (elt coord 0) (elt aabb 2))
      (setf (elt cp 2) (elt coord 0)))
    (when (< (elt coord 1) (elt aabb 1))
      (setf (elt cp 1) (elt coord 1)))
    (when (> (elt coord 1) (elt aabb 3))
      (setf (elt cp 3) (elt coord 1)))
    cp))

(defun union-iaabb2 (aabb aabb2)
  (let ((cp (copy-ivec4 aabb)))
    (setf cp (expand-iaabb2 cp (subseq aabb2 0 2)))
    (setf cp (expand-iaabb2 cp (list (elt aabb2 2) (elt aabb2 1))))
    (setf cp (expand-iaabb2 cp (list (elt aabb2 2) (elt aabb2 3))))
    (setf cp (expand-iaabb2 cp (list (elt aabb2 0) (elt aabb2 3))))
    cp))

(defun iaabb2->irect2 (coords)
  "(upper-left-x upper-left-y bottom-right-x bottom-right-y) to
   (upper-left-x upper-left-y  w h)"
  (let ((x1 (elt coords 0))
        (y1 (elt coords 1))
        (x2 (elt coords 2))
        (y2 (elt coords 3)))
  (ivec4 x1 y1 (- x2 x1) (- y2 y1))))

(defun irect2->iaabb2 (coords)
  "(upper-left-x upper-left-y  w h) to
   (upper-left-x upper-left-y bottom-right-x bottom-right-y)"
  (let ((x1 (elt coords 0))
        (y1 (elt coords 1))
        (w  (elt coords 2))
        (h  (elt coords 3)))
  (ivec4 x1 y1 (+ x1 w) (+ y1 h))))

(defun irect2->iaabb2* (&rest coords)
  (irect2->iaabb2 coords))

(defun inside-iaabb2-p (aabb x y)
  "t if x y is inside this bounding box
   aabb is: (upper-left-x upper-left-y bottom-right-x bottom-right-y)"
  (and
   (>= x (elt aabb 0))
   (<= x (elt aabb 2))
   (>= y (elt aabb 1))
   (<= y (elt aabb 3))))

(defun iaabb2-intersect-p (aabb1 aabb2)
  (if (or (>= (iaabb2-min-x aabb1) (iaabb2-max-x aabb2))
          (<= (iaabb2-max-x aabb1) (iaabb2-min-x aabb2))
          (>= (iaabb2-min-y aabb1) (iaabb2-max-y aabb2))
          (<= (iaabb2-max-y aabb1) (iaabb2-min-y aabb2)))
      nil
      t))

(defun iaabb2-inglobe-p (host guest)
  (and (inside-iaabb2-p host (iaabb2-min-x guest) (iaabb2-min-x guest))
       (inside-iaabb2-p host (iaabb2-max-x guest) (iaabb2-max-x guest))))

(defun iaabb2-null-p (aabb)
  (let ((rect (iaabb2->irect2 aabb)))
    (and (= 0 (elt rect 2))
         (= 0 (elt rect 3)))))

(defun trasl-iaabb2 (aabb &optional (dx (- (elt aabb 0))) (dy (- (elt aabb 1))))
  (list (+ (elt aabb 0) dx)
         (+ (elt aabb 1) dy)
         (+ (elt aabb 2) dx)
         (+ (elt aabb 3) dy)))

(defun trasl-irect2 (rect &optional (dx (- (elt rect 0))) (dy (- (elt rect 1))))
  (list (+ (elt rect 0) dx)
         (+ (elt rect 1) dy)
         (elt rect 2)
         (elt rect 3)))

(defun center-iaabb2 (aabb)
  (let ((rect (iaabb2->irect2 aabb)))
    (list (+ (elt rect 0) (/ (elt rect 2) 2))
          (+ (elt rect 1) (/ (elt rect 3) 2)))))