mirror of
https://github.com/unidoc/unipdf.git
synced 2025-05-02 22:17:06 +08:00
d961079c5d
* Add render package * Add text state * Add more text operators * Remove unnecessary files * Add text font * Add custom text render method * Improve text rendering method * Rename text state methods * Refactor and document context interface * Refact text begin/end operators * Fix graphics state transformations * Keep original font when doing font substitution * Take page cropbox into account * Revert to substitution font if original font measurement is 0 * Add font substitution package * Implement addition transform.Point methods * Use transform.Point in the image context package * Remove unneeded functionality from the render image package * Fix golint notices in the image rendering package * Fix go vet notices in the render package * Fix golint notices in the top-level render package * Improve render context package documentation * Document context text state struct. * Document context text font struct. * Minor logging improvements * Add license disclaimer to the render package files * Avoid using package aliases where possible * Change style of section comments * Adapt render package import style to follow the developer guide * Improve documentation for the internal matrix implementation * Update render package dependency versions * Apply crop box post render * Account for offseted media boxes * Improve metrics of rendered characters * Fix text matrix translation * Change priority of fonts used for measuring rendered characters * Skip invalid m and l operators on image rendering * Small fix for v operator * Fix rendered characters spacing issues * Refactor naming of internal render packages
69 lines
1.4 KiB
Go
69 lines
1.4 KiB
Go
/*
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* This file is subject to the terms and conditions defined in
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* file 'LICENSE.md', which is part of this source code package.
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*/
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package imagerender
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import (
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"math"
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"github.com/unidoc/unipdf/v3/internal/transform"
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)
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func quadratic(x0, y0, x1, y1, x2, y2, t float64) (x, y float64) {
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u := 1 - t
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a := u * u
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b := 2 * u * t
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c := t * t
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x = a*x0 + b*x1 + c*x2
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y = a*y0 + b*y1 + c*y2
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return
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}
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func quadraticBezier(x0, y0, x1, y1, x2, y2 float64) []transform.Point {
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l := (math.Hypot(x1-x0, y1-y0) +
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math.Hypot(x2-x1, y2-y1))
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n := int(l + 0.5)
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if n < 4 {
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n = 4
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}
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d := float64(n) - 1
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result := make([]transform.Point, n)
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for i := 0; i < n; i++ {
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t := float64(i) / d
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x, y := quadratic(x0, y0, x1, y1, x2, y2, t)
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result[i] = transform.NewPoint(x, y)
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}
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return result
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}
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func cubic(x0, y0, x1, y1, x2, y2, x3, y3, t float64) (x, y float64) {
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u := 1 - t
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a := u * u * u
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b := 3 * u * u * t
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c := 3 * u * t * t
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d := t * t * t
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x = a*x0 + b*x1 + c*x2 + d*x3
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y = a*y0 + b*y1 + c*y2 + d*y3
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return
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}
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func cubicBezier(x0, y0, x1, y1, x2, y2, x3, y3 float64) []transform.Point {
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l := (math.Hypot(x1-x0, y1-y0) +
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math.Hypot(x2-x1, y2-y1) +
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math.Hypot(x3-x2, y3-y2))
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n := int(l + 0.5)
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if n < 4 {
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n = 4
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}
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d := float64(n) - 1
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result := make([]transform.Point, n)
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for i := 0; i < n; i++ {
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t := float64(i) / d
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x, y := cubic(x0, y0, x1, y1, x2, y2, x3, y3, t)
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result[i] = transform.NewPoint(x, y)
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}
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return result
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}
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