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|
package gg
import (
"fmt"
"image"
"image/draw"
"image/jpeg"
_ "image/jpeg"
"image/png"
"io/ioutil"
"math"
"os"
"strings"
"github.com/golang/freetype/truetype"
"golang.org/x/image/font"
"golang.org/x/image/math/fixed"
)
func Radians(degrees float64) float64 {
return degrees * math.Pi / 180
}
func Degrees(radians float64) float64 {
return radians * 180 / math.Pi
}
func LoadImage(path string) (image.Image, error) {
file, err := os.Open(path)
if err != nil {
return nil, err
}
defer file.Close()
im, _, err := image.Decode(file)
return im, err
}
func LoadPNG(path string) (image.Image, error) {
file, err := os.Open(path)
if err != nil {
return nil, err
}
defer file.Close()
return png.Decode(file)
}
func SavePNG(path string, im image.Image) error {
file, err := os.Create(path)
if err != nil {
return err
}
defer file.Close()
return png.Encode(file, im)
}
func LoadJPG(path string) (image.Image, error) {
file, err := os.Open(path)
if err != nil {
return nil, err
}
defer file.Close()
return jpeg.Decode(file)
}
func SaveJPG(path string, im image.Image, quality int) error {
file, err := os.Create(path)
if err != nil {
return err
}
defer file.Close()
var opt jpeg.Options
opt.Quality = quality
return jpeg.Encode(file, im, &opt)
}
func imageToRGBA(src image.Image) *image.RGBA {
bounds := src.Bounds()
dst := image.NewRGBA(bounds)
draw.Draw(dst, bounds, src, bounds.Min, draw.Src)
return dst
}
func parseHexColor(x string) (r, g, b, a int) {
x = strings.TrimPrefix(x, "#")
a = 255
if len(x) == 3 {
format := "%1x%1x%1x"
fmt.Sscanf(x, format, &r, &g, &b)
r |= r << 4
g |= g << 4
b |= b << 4
}
if len(x) == 6 {
format := "%02x%02x%02x"
fmt.Sscanf(x, format, &r, &g, &b)
}
if len(x) == 8 {
format := "%02x%02x%02x%02x"
fmt.Sscanf(x, format, &r, &g, &b, &a)
}
return
}
func fixp(x, y float64) fixed.Point26_6 {
return fixed.Point26_6{fix(x), fix(y)}
}
func fix(x float64) fixed.Int26_6 {
return fixed.Int26_6(x * 64)
}
func unfix(x fixed.Int26_6) float64 {
const shift, mask = 6, 1<<6 - 1
if x >= 0 {
return float64(x>>shift) + float64(x&mask)/64
}
x = -x
if x >= 0 {
return -(float64(x>>shift) + float64(x&mask)/64)
}
return 0
}
// LoadFontFace is a helper function to load the specified font file with
// the specified point size. Note that the returned `font.Face` objects
// are not thread safe and cannot be used in parallel across goroutines.
// You can usually just use the Context.LoadFontFace function instead of
// this package-level function.
func LoadFontFace(path string, points float64) (font.Face, error) {
fontBytes, err := ioutil.ReadFile(path)
if err != nil {
return nil, err
}
f, err := truetype.Parse(fontBytes)
if err != nil {
return nil, err
}
face := truetype.NewFace(f, &truetype.Options{
Size: points,
// Hinting: font.HintingFull,
})
return face, nil
}
|
