| // Copyright 2016 The Go 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 widget |
| |
| import ( |
| "testing" |
| |
| "golang.org/x/exp/shiny/unit" |
| "golang.org/x/image/math/fixed" |
| ) |
| |
| func TestThemeIsAUnitConverter(t *testing.T) { |
| // 1.5 inches (at the default 72 DPI) should be 108 pixels. |
| c := unit.Converter(DefaultTheme) |
| got := c.Pixels(unit.Inches(1.5)) |
| want := fixed.I(108) |
| if got != want { |
| t.Errorf("1 inch in pixels: got %v, want %v", got, want) |
| } |
| |
| // 3 em (at basicfont.Face7x13's 13 pixel em-height) should be 39 pixels, |
| // regardless of the DPI. basicfont.Face7x13 is a bitmap font, so its |
| // height does not depend on the DPI. 39 pixels is 39 points at 72 DPI, and |
| // 39 pixels is 17.55 points at 160 DPI. |
| for _, dpi := range []float64{72, 160} { |
| c := unit.Converter(&Theme{ |
| DPI: dpi, |
| }) |
| got := c.Convert(unit.Ems(3), unit.Pt) |
| want := unit.Points(39 * unit.PointsPerInch / dpi) |
| if got != want { |
| t.Errorf("dpi=%v: 3 em in points: got %v, want %v", dpi, got, want) |
| } |
| } |
| } |