ebiten/internal/mipmap/mipmap_test.go
Hajime Hoshi c99fd1a742 mipmap: Create mipmap package and bufferd.Image uses it
Mipmap calculation must be executed after the main loop starts
because the graphics driver's HasHighPrecisionFloat is needed.
Then, operations on mipmap images must be called from images in
buffered package.

Updates #1044
2020-01-08 02:06:01 +09:00

64 lines
1.5 KiB
Go

// Copyright 2018 The Ebiten 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 mipmap_test
import (
"math"
"testing"
. "github.com/hajimehoshi/ebiten/internal/mipmap"
)
func TestMipmapLevelForDownscale(t *testing.T) {
inf := float32(math.Inf(1))
cases := []struct {
In float32
Out int
}{
{1, 0},
{-1, 0},
{2, 0},
{-2, 0},
{100, 0},
{-100, 0},
{1.0 / 2.0, 0},
{-1.0 / 2.0, 0},
{1.0 / 4.0, 0},
{-1.0 / 4.0, 0},
{math.Nextafter32(1.0/4.0, 0), 1},
{math.Nextafter32(-1.0/4.0, 0), 1},
{1.0 / 8.0, 1},
{-1.0 / 8.0, 1},
{1.0 / 16.0, 1},
{-1.0 / 16.0, 1},
{math.Nextafter32(1.0/16.0, 0), 2},
{math.Nextafter32(-1.0/16.0, 0), 2},
{math.Nextafter32(1.0/256.0, 0), 4},
{math.Nextafter32(-1.0/256.0, 0), 4},
{math.SmallestNonzeroFloat32, 74},
{-math.SmallestNonzeroFloat32, 74},
{inf, 0},
{-inf, 0},
}
for _, c := range cases {
got := MipmapLevelForDownscale(c.In)
want := c.Out
if got != want {
t.Errorf("MipmapLevel(%v): got %v, want %v", c.In, got, want)
}
}
}