go-chart/drawing/stack_graphic_context.go
2016-07-08 17:57:14 -07:00

184 lines
4.3 KiB
Go

package drawing
import (
"image"
"image/color"
"github.com/golang/freetype/truetype"
)
// StackGraphicContext is a context that does thngs.
type StackGraphicContext struct {
current *ContextStack
}
// ContextStack is a graphic context implementation.
type ContextStack struct {
Tr Matrix
Path *Path
LineWidth float64
Dash []float64
DashOffset float64
StrokeColor color.Color
FillColor color.Color
FillRule FillRule
Cap LineCap
Join LineJoin
FontSize float64
Font *truetype.Font
Scale float64
Previous *ContextStack
}
// NewStackGraphicContext Create a new Graphic context from an image
func NewStackGraphicContext() *StackGraphicContext {
gc := &StackGraphicContext{}
gc.current = new(ContextStack)
gc.current.Tr = NewIdentityMatrix()
gc.current.Path = new(Path)
gc.current.LineWidth = 1.0
gc.current.StrokeColor = image.Black
gc.current.FillColor = image.White
gc.current.Cap = RoundCap
gc.current.FillRule = FillRuleEvenOdd
gc.current.Join = RoundJoin
gc.current.FontSize = 10
return gc
}
func (gc *StackGraphicContext) GetMatrixTransform() Matrix {
return gc.current.Tr
}
func (gc *StackGraphicContext) SetMatrixTransform(Tr Matrix) {
gc.current.Tr = Tr
}
func (gc *StackGraphicContext) ComposeMatrixTransform(Tr Matrix) {
gc.current.Tr.Compose(Tr)
}
func (gc *StackGraphicContext) Rotate(angle float64) {
gc.current.Tr.Rotate(angle)
}
func (gc *StackGraphicContext) Translate(tx, ty float64) {
gc.current.Tr.Translate(tx, ty)
}
func (gc *StackGraphicContext) Scale(sx, sy float64) {
gc.current.Tr.Scale(sx, sy)
}
func (gc *StackGraphicContext) SetStrokeColor(c color.Color) {
gc.current.StrokeColor = c
}
func (gc *StackGraphicContext) SetFillColor(c color.Color) {
gc.current.FillColor = c
}
func (gc *StackGraphicContext) SetFillRule(f FillRule) {
gc.current.FillRule = f
}
func (gc *StackGraphicContext) SetLineWidth(lineWidth float64) {
gc.current.LineWidth = lineWidth
}
func (gc *StackGraphicContext) SetLineCap(cap LineCap) {
gc.current.Cap = cap
}
func (gc *StackGraphicContext) SetLineJoin(join LineJoin) {
gc.current.Join = join
}
func (gc *StackGraphicContext) SetLineDash(dash []float64, dashOffset float64) {
gc.current.Dash = dash
gc.current.DashOffset = dashOffset
}
func (gc *StackGraphicContext) SetFontSize(fontSize float64) {
gc.current.FontSize = fontSize
}
func (gc *StackGraphicContext) GetFontSize() float64 {
return gc.current.FontSize
}
func (gc *StackGraphicContext) SetFont(f *truetype.Font) {
gc.current.Font = f
}
func (gc *StackGraphicContext) GetFont() *truetype.Font {
return gc.current.Font
}
func (gc *StackGraphicContext) BeginPath() {
gc.current.Path.Clear()
}
func (gc *StackGraphicContext) IsEmpty() bool {
return gc.current.Path.IsEmpty()
}
func (gc *StackGraphicContext) LastPoint() (float64, float64) {
return gc.current.Path.LastPoint()
}
func (gc *StackGraphicContext) MoveTo(x, y float64) {
gc.current.Path.MoveTo(x, y)
}
func (gc *StackGraphicContext) LineTo(x, y float64) {
gc.current.Path.LineTo(x, y)
}
func (gc *StackGraphicContext) QuadCurveTo(cx, cy, x, y float64) {
gc.current.Path.QuadCurveTo(cx, cy, x, y)
}
func (gc *StackGraphicContext) CubicCurveTo(cx1, cy1, cx2, cy2, x, y float64) {
gc.current.Path.CubicCurveTo(cx1, cy1, cx2, cy2, x, y)
}
func (gc *StackGraphicContext) ArcTo(cx, cy, rx, ry, startAngle, angle float64) {
gc.current.Path.ArcTo(cx, cy, rx, ry, startAngle, angle)
}
func (gc *StackGraphicContext) Close() {
gc.current.Path.Close()
}
func (gc *StackGraphicContext) Save() {
context := new(ContextStack)
context.FontSize = gc.current.FontSize
context.Font = gc.current.Font
context.LineWidth = gc.current.LineWidth
context.StrokeColor = gc.current.StrokeColor
context.FillColor = gc.current.FillColor
context.FillRule = gc.current.FillRule
context.Dash = gc.current.Dash
context.DashOffset = gc.current.DashOffset
context.Cap = gc.current.Cap
context.Join = gc.current.Join
context.Path = gc.current.Path.Copy()
context.Font = gc.current.Font
context.Scale = gc.current.Scale
copy(context.Tr[:], gc.current.Tr[:])
context.Previous = gc.current
gc.current = context
}
func (gc *StackGraphicContext) Restore() {
if gc.current.Previous != nil {
oldContext := gc.current
gc.current = gc.current.Previous
oldContext.Previous = nil
}
}