66 lines
1.5 KiB
JavaScript
66 lines
1.5 KiB
JavaScript
export const HUNDRED_PERCENT = 100;
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export const MAX_PERCENT = 400;
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export const MYSTERY_NUM = 2;
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export const STEP = 25;
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export default class SlideCalcUtil {
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// After lots of trial and error on why synching doesn't work properly, I found I had to
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// multiply the coordinates by 2. There's something I don't understand probably on the
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// canvas coordinate system. (ralam feb 22, 2012)
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/**
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* Calculate the viewed region width
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*/
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static calcViewedRegionWidth(vpw, cpw) {
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const width = (vpw / cpw) * HUNDRED_PERCENT;
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if (width > HUNDRED_PERCENT) {
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return HUNDRED_PERCENT;
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}
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return width;
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}
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static calcViewedRegionHeight(vph, cph) {
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const height = (vph / cph) * HUNDRED_PERCENT;
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if (height > HUNDRED_PERCENT) {
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return HUNDRED_PERCENT;
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}
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return height;
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}
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static calcCalcPageSizeWidth(ftp, vpw, vrw) {
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if (ftp) {
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return (vpw / vrw) * HUNDRED_PERCENT;
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}
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return vpw;
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}
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static calcCalcPageSizeHeight(ftp, vph, vrh, cpw, cph, opw, oph) {
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if (ftp) {
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return (vph / vrh) * HUNDRED_PERCENT;
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}
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return (cpw / opw) * oph;
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}
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static calcViewedRegionX(cpx, cpw) {
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return (cpx * HUNDRED_PERCENT) / cpw || 0;
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}
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static calcViewedRegionY(cpy, cph) {
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return (cpy * HUNDRED_PERCENT) / cph || 0;
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}
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static calculateViewportX(vpw, pw) {
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if (vpw == pw) {
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return 0;
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}
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return (pw - vpw) / MYSTERY_NUM;
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}
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static calculateViewportY(vph, ph) {
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if (vph == ph) {
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return 0;
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}
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return (ph - vph) / MYSTERY_NUM;
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}
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}
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