diff --git a/text/v2/export_test.go b/text/v2/export_test.go new file mode 100644 index 000000000..3f42d202a --- /dev/null +++ b/text/v2/export_test.go @@ -0,0 +1,35 @@ +// Copyright 2023 The Ebitengine Authors +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package text + +import ( + "golang.org/x/image/math/fixed" +) + +func Fixed26_6ToFloat32(x fixed.Int26_6) float32 { + return fixed26_6ToFloat32(x) +} + +func Fixed26_6ToFloat64(x fixed.Int26_6) float64 { + return fixed26_6ToFloat64(x) +} + +func Float32ToFixed26_6(x float32) fixed.Int26_6 { + return float32ToFixed26_6(x) +} + +func Float64ToFixed26_6(x float64) fixed.Int26_6 { + return float64ToFixed26_6(x) +} diff --git a/text/v2/text.go b/text/v2/text.go index 9d133435b..3e47aa770 100644 --- a/text/v2/text.go +++ b/text/v2/text.go @@ -18,7 +18,6 @@ package text import ( - "math" "strings" "golang.org/x/image/math/fixed" @@ -72,23 +71,19 @@ type Metrics struct { } func fixed26_6ToFloat32(x fixed.Int26_6) float32 { - return float32(x>>6) + float32(x&((1<<6)-1))/float32(1<<6) + return float32(x) / (1 << 6) } func fixed26_6ToFloat64(x fixed.Int26_6) float64 { - return float64(x>>6) + float64(x&((1<<6)-1))/float64(1<<6) + return float64(x) / (1 << 6) } func float32ToFixed26_6(x float32) fixed.Int26_6 { - i := float32(math.Floor(float64(x))) - frac := x - i - return fixed.Int26_6(i)<<6 + fixed.Int26_6(frac*(1<<6)) + return fixed.Int26_6(x * (1 << 6)) } func float64ToFixed26_6(x float64) fixed.Int26_6 { - i := math.Floor(x) - frac := x - i - return fixed.Int26_6(i)<<6 + fixed.Int26_6(frac*(1<<6)) + return fixed.Int26_6(x * (1 << 6)) } func glyphVariationCount(face Face) int { diff --git a/text/v2/text_test.go b/text/v2/text_test.go index 21b258012..fb7aa6089 100644 --- a/text/v2/text_test.go +++ b/text/v2/text_test.go @@ -240,3 +240,119 @@ func TestUnhashableFace(t *testing.T) { } } } + +func TestConvertToFixed26_6(t *testing.T) { + testCases := []struct { + In float64 + Out fixed.Int26_6 + }{ + { + In: 0, + Out: 0, + }, + { + In: 0.25, + Out: fixed.I(1) / 4, + }, + { + In: 0.5, + Out: fixed.I(1) / 2, + }, + { + In: 1.25, + Out: fixed.I(1) * 5 / 4, + }, + { + In: 1, + Out: fixed.I(1), + }, + { + In: -0.25, + Out: fixed.I(-1) / 4, + }, + { + In: -0.5, + Out: fixed.I(-1) / 2, + }, + { + In: -1, + Out: fixed.I(-1), + }, + { + In: -1.25, + Out: fixed.I(-1) * 5 / 4, + }, + } + + for _, tc := range testCases { + got := text.Float32ToFixed26_6(float32(tc.In)) + want := tc.Out + if got != want { + t.Errorf("Float32ToFixed26_6(%v): got: %v, want: %v", tc.In, got, want) + } + + got = text.Float64ToFixed26_6(tc.In) + want = tc.Out + if got != want { + t.Errorf("Float32ToFixed26_6(%v): got: %v, want: %v", tc.In, got, want) + } + } +} + +func TestConvertToFloat(t *testing.T) { + testCases := []struct { + In fixed.Int26_6 + Out float64 + }{ + { + In: 0, + Out: 0, + }, + { + In: fixed.I(1) / 4, + Out: 0.25, + }, + { + In: fixed.I(1) / 2, + Out: 0.5, + }, + { + In: fixed.I(1) * 5 / 4, + Out: 1.25, + }, + { + In: fixed.I(1), + Out: 1, + }, + { + In: fixed.I(-1) / 4, + Out: -0.25, + }, + { + In: fixed.I(-1) / 2, + Out: -0.5, + }, + { + In: fixed.I(-1), + Out: -1, + }, + { + In: fixed.I(-1) * 5 / 4, + Out: -1.25, + }, + } + + for _, tc := range testCases { + got := text.Fixed26_6ToFloat32(tc.In) + want := float32(tc.Out) + if got != want { + t.Errorf("Fixed26_6ToFloat32(%v): got: %v, want: %v", tc.In, got, want) + } + + got64 := text.Fixed26_6ToFloat64(tc.In) + want64 := tc.Out + if got64 != want64 { + t.Errorf("Fixed26_6ToFloat64(%v): got: %v, want: %v", tc.In, got64, want64) + } + } +}