func test(t *testing.T, draw sample) {
// Initialize the graphic context on an RGBA image
dest := image.NewRGBA(image.Rect(0, 0, 297, 210.0))
gc := draw2dimg.NewGraphicContext(dest)
// Draw Android logo
output, err := draw(gc, "png")
if err != nil {
t.Errorf("Drawing %q failed: %v", output, err)
return
}
// Save to png
err = draw2dimg.SaveToPngFile(output, dest)
if err != nil {
t.Errorf("Saving %q failed: %v", output, err)
}
}
// AddTo returns a new ImageGraphics which will write to (width x height) sized
// area starting at (x,y) on the provided image img. The rest of the parameters
// are the same as in New().
func AddTo(img *image.RGBA, x, y, width, height int, bgcol color.RGBA, font *truetype.Font, fontsize map[chart.FontSize]float64) *ImageGraphics {
gc := draw2dimg.NewGraphicContext(img)
gc.SetLineJoin(draw2d.BevelJoin)
gc.SetLineCap(draw2d.SquareCap)
gc.SetStrokeColor(image.Black)
gc.SetFillColor(bgcol)
gc.Translate(float64(x)+0.5, float64(y)+0.5)
gc.ClearRect(x, y, x+width, y+height)
if font == nil {
font = defaultFont
}
if len(fontsize) == 0 {
fontsize = ConstructFontSizes(13)
}
return &ImageGraphics{Image: img, x0: x, y0: y, w: width, h: height, bg: bgcol, gc: gc, font: font, fs: fontsize}
}
// New creates a new ImageGraphics including an image.RGBA of dimension w x h
// with background bgcol. If font is nil it will use a builtin font.
// If fontsize is empty useful default are used.
func New(width, height int, bgcol color.RGBA, font *truetype.Font, fontsize map[chart.FontSize]float64) *ImageGraphics {
img := image.NewRGBA(image.Rect(0, 0, width, height))
gc := draw2dimg.NewGraphicContext(img)
gc.SetLineJoin(draw2d.BevelJoin)
gc.SetLineCap(draw2d.SquareCap)
gc.SetStrokeColor(image.Black)
gc.SetFillColor(bgcol)
gc.Translate(0.5, 0.5)
gc.Clear()
if font == nil {
font = defaultFont
}
if len(fontsize) == 0 {
fontsize = ConstructFontSizes(13)
}
return &ImageGraphics{Image: img, x0: 0, y0: 0, w: width, h: height,
bg: bgcol, gc: gc, font: font, fs: fontsize}
}