Accurate vertical positioning of text+return fractional bearing/descent

main_test.go

@@ -0,0 +1,46 @@
+package main_test
+
+import (
+	"testing"
+
+	"github.com/bloeys/nterm/glyphs"
+	"golang.org/x/image/math/fixed"
+)
+
+func TestI26_6ToF32(t *testing.T) {
+
+	x := fixed.I(55)
+	var ans float32 = 55
+	Check(t, ans, glyphs.I26_6ToF32(x))
+
+	x = fixed.I(-10)
+	ans = -10
+	Check(t, ans, glyphs.I26_6ToF32(x))
+
+	x = fixed.Int26_6(0<<6 + 1<<0)
+	ans = 1 / 64.0
+	Check(t, ans, glyphs.I26_6ToF32(x))
+
+	x = fixed.Int26_6(12<<6 + 0<<0)
+	ans = 12
+	Check(t, ans, glyphs.I26_6ToF32(x))
+
+	x = fixed.Int26_6(-3<<6 + 1<<2)
+	ans = -(3.0 + 4/64.0)
+	Check(t, ans, glyphs.I26_6ToF32(x))
+
+	//Test min/max values
+	x = fixed.I(33554431)
+	ans = 33554431
+	Check(t, ans, glyphs.I26_6ToF32(x))
+
+	x = fixed.I(-33554432)
+	ans = -33554432
+	Check(t, ans, glyphs.I26_6ToF32(x))
+}
+
+func Check[T comparable](t *testing.T, expected, got T) {
+	if got != expected {
+		t.Fatalf("Expected %v but got %v\n", expected, got)
+	}
+}