Files
sjy01-image-proc/vendor/gonum.org/v1/plot/vg/tee.go
2024-10-24 15:46:01 +08:00

130 lines
3.0 KiB
Go

// Copyright ©2020 The Gonum Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package vg
import (
"image"
"image/color"
"gonum.org/v1/plot/font"
)
// MultiCanvas creates a canvas that duplicates its drawing operations to all
// the provided canvases, similar to the Unix tee(1) command.
//
// Each drawing operation is sent to each listed canvas, one at a time.
func MultiCanvas(cs ...Canvas) Canvas {
return teeCanvas{cs}
}
type teeCanvas struct {
cs []Canvas
}
// SetLineWidth sets the width of stroked paths.
// If the width is not positive then stroked lines
// are not drawn.
func (tee teeCanvas) SetLineWidth(w Length) {
for _, c := range tee.cs {
c.SetLineWidth(w)
}
}
// SetLineDash sets the dash pattern for lines.
// The pattern slice specifies the lengths of
// alternating dashes and gaps, and the offset
// specifies the distance into the dash pattern
// to start the dash.
func (tee teeCanvas) SetLineDash(pattern []Length, offset Length) {
for _, c := range tee.cs {
c.SetLineDash(pattern, offset)
}
}
// SetColor sets the current drawing color.
// Note that fill color and stroke color are
// the same, so if you want different fill
// and stroke colors then you must set a color,
// draw fills, set a new color and then draw lines.
func (tee teeCanvas) SetColor(c color.Color) {
for _, canvas := range tee.cs {
canvas.SetColor(c)
}
}
// Rotate applies a rotation transform to the context.
// The parameter is specified in radians.
func (tee teeCanvas) Rotate(rad float64) {
for _, c := range tee.cs {
c.Rotate(rad)
}
}
// Translate applies a translational transform to the context.
func (tee teeCanvas) Translate(pt Point) {
for _, c := range tee.cs {
c.Translate(pt)
}
}
// Scale applies a scaling transform to the context.
func (tee teeCanvas) Scale(x, y float64) {
for _, c := range tee.cs {
c.Scale(x, y)
}
}
// Push saves the current line width, the
// current dash pattern, the current
// transforms, and the current color
// onto a stack so that the state can later
// be restored by calling Pop().
func (tee teeCanvas) Push() {
for _, c := range tee.cs {
c.Push()
}
}
// Pop restores the context saved by the
// corresponding call to Push().
func (tee teeCanvas) Pop() {
for _, c := range tee.cs {
c.Pop()
}
}
// Stroke strokes the given path.
func (tee teeCanvas) Stroke(p Path) {
for _, c := range tee.cs {
c.Stroke(p)
}
}
// Fill fills the given path.
func (tee teeCanvas) Fill(p Path) {
for _, c := range tee.cs {
c.Fill(p)
}
}
// FillString fills in text at the specified
// location using the given font.
// If the font size is zero, the text is not drawn.
func (tee teeCanvas) FillString(f font.Face, pt Point, text string) {
for _, c := range tee.cs {
c.FillString(f, pt, text)
}
}
// DrawImage draws the image, scaled to fit
// the destination rectangle.
func (tee teeCanvas) DrawImage(rect Rectangle, img image.Image) {
for _, c := range tee.cs {
c.DrawImage(rect, img)
}
}
var _ Canvas = (*teeCanvas)(nil)