penpot/frontend/src/app/util/thumbnails.cljs
2024-01-08 09:32:50 +01:00

57 lines
2.0 KiB
Clojure

;; This Source Code Form is subject to the terms of the Mozilla Public
;; License, v. 2.0. If a copy of the MPL was not distributed with this
;; file, You can obtain one at http://mozilla.org/MPL/2.0/.
;;
;; Copyright (c) KALEIDOS INC
(ns app.util.thumbnails
(:require
[app.common.math :as mth]))
(def ^:const max-recommended-size (mth/pow 2 11)) ;; 2^11 = 2048
(def ^:const max-absolute-size (mth/pow 2 14)) ;; 2^14 = 16384
(def ^:const min-size 1)
(def ^:const max-size max-recommended-size)
(def ^:const min-aspect-ratio 0.5)
(def ^:const max-aspect-ratio 2.0)
(defn get-aspect-ratio
"Returns the aspect ratio of a given width and height."
[width height]
(/ width height))
(defn get-size-from
[ref-size opp-size clamped-size]
(/ (* opp-size clamped-size) ref-size))
(defn get-height-from-width
([width height clamped-width]
(get-size-from width height clamped-width)))
(defn get-width-from-height
([width height clamped-height]
(get-size-from height width clamped-height)))
(defn get-proportional-size
"Returns a proportional size given a width and height and some size constraints."
([width height]
(get-proportional-size width height min-size max-size min-size max-size))
([width height min-size max-size]
(get-proportional-size width height min-size max-size min-size max-size))
([width height min-width max-width min-height max-height]
(let [clamped-width (mth/clamp width min-width max-width)
clamped-height (mth/clamp height min-height max-height)]
(if (> width height)
[clamped-width (get-height-from-width width height clamped-width)]
[(get-width-from-height width height clamped-height) clamped-height]))))
(defn get-relative-size
"Returns a recommended size given a width and height."
[width height]
(let [aspect-ratio (get-aspect-ratio width height)]
(if (or (< aspect-ratio min-aspect-ratio) (> aspect-ratio max-aspect-ratio))
(get-proportional-size width height min-size max-absolute-size)
(get-proportional-size width height min-size max-recommended-size))))