package drawing import ( "image" "image/color" "git.gutmet.org/golang-freetype.git/truetype" ) // GraphicContext describes the interface for the various backends (images, pdf, opengl, ...) type GraphicContext interface { // PathBuilder describes the interface for path drawing PathBuilder // BeginPath creates a new path BeginPath() // GetMatrixTransform returns the current transformation matrix GetMatrixTransform() Matrix // SetMatrixTransform sets the current transformation matrix SetMatrixTransform(tr Matrix) // ComposeMatrixTransform composes the current transformation matrix with tr ComposeMatrixTransform(tr Matrix) // Rotate applies a rotation to the current transformation matrix. angle is in radian. Rotate(angle float64) // Translate applies a translation to the current transformation matrix. Translate(tx, ty float64) // Scale applies a scale to the current transformation matrix. Scale(sx, sy float64) // SetStrokeColor sets the current stroke color SetStrokeColor(c color.Color) // SetFillColor sets the current fill color SetFillColor(c color.Color) // SetFillRule sets the current fill rule SetFillRule(f FillRule) // SetLineWidth sets the current line width SetLineWidth(lineWidth float64) // SetLineCap sets the current line cap SetLineCap(cap LineCap) // SetLineJoin sets the current line join SetLineJoin(join LineJoin) // SetLineDash sets the current dash SetLineDash(dash []float64, dashOffset float64) // SetFontSize sets the current font size SetFontSize(fontSize float64) // GetFontSize gets the current font size GetFontSize() float64 // SetFont sets the font for the context SetFont(f *truetype.Font) // GetFont returns the current font GetFont() *truetype.Font // DrawImage draws the raster image in the current canvas DrawImage(image image.Image) // Save the context and push it to the context stack Save() // Restore remove the current context and restore the last one Restore() // Clear fills the current canvas with a default transparent color Clear() // ClearRect fills the specified rectangle with a default transparent color ClearRect(x1, y1, x2, y2 int) // SetDPI sets the current DPI SetDPI(dpi int) // GetDPI gets the current DPI GetDPI() int // GetStringBounds gets pixel bounds(dimensions) of given string GetStringBounds(s string) (left, top, right, bottom float64) // CreateStringPath creates a path from the string s at x, y CreateStringPath(text string, x, y float64) (cursor float64) // FillString draws the text at point (0, 0) FillString(text string) (cursor float64) // FillStringAt draws the text at the specified point (x, y) FillStringAt(text string, x, y float64) (cursor float64) // StrokeString draws the contour of the text at point (0, 0) StrokeString(text string) (cursor float64) // StrokeStringAt draws the contour of the text at point (x, y) StrokeStringAt(text string, x, y float64) (cursor float64) // Stroke strokes the paths with the color specified by SetStrokeColor Stroke(paths ...*Path) // Fill fills the paths with the color specified by SetFillColor Fill(paths ...*Path) // FillStroke first fills the paths and than strokes them FillStroke(paths ...*Path) }