ui: basic map scroller

2026-03-06 23:29:06 +02:00
parent 29d188969b
commit 1de621c743
68 changed files with 9861 additions and 118 deletions
@@ -0,0 +1,114 @@
+package world
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestRender_PanSmall_UsesCopyShiftAndRendersOnlyDirtyStrips(t *testing.T) {
+	t.Parallel()
+
+	w := NewWorld(10, 10)
+	w.resetGrid(2 * SCALE)
+
+	_, err := w.AddPoint(5, 5)
+	require.NoError(t, err)
+	_, err = w.AddCircle(2, 2, 1)
+	require.NoError(t, err)
+	_, err = w.AddLine(9, 5, 1, 5)
+	require.NoError(t, err)
+
+	for _, obj := range w.objects {
+		w.indexObject(obj)
+	}
+
+	params := RenderParams{
+		ViewportWidthPx:  10,
+		ViewportHeightPx: 10,
+		MarginXPx:        4, // threshold=2
+		MarginYPx:        4, // threshold=2
+		CameraXWorldFp:   5 * SCALE,
+		CameraYWorldFp:   5 * SCALE,
+		CameraZoom:       1.0,
+	}
+
+	// First render initializes state (full redraw).
+	d0 := &fakePrimitiveDrawer{}
+	require.NoError(t, w.Render(d0, params))
+
+	// Pan right by 1 unit => dx=-1 => incremental shift expected.
+	params2 := params
+	params2.CameraXWorldFp += 1 * SCALE
+
+	d := &fakePrimitiveDrawer{}
+	err = w.Render(d, params2)
+	require.NoError(t, err)
+
+	// Must contain CopyShift for incremental path.
+	require.NotEmpty(t, d.CommandsByName("CopyShift"))
+
+	// All clip rects should be "small": width <= 1 for dx=-1 strip.
+	clipCmds := d.CommandsByName("ClipRect")
+	require.NotEmpty(t, clipCmds)
+	for _, c := range clipCmds {
+		wPx := int(c.Args[2])
+		hPx := int(c.Args[3])
+		require.LessOrEqual(t, wPx, 2)
+		require.LessOrEqual(t, hPx, params2.CanvasHeightPx())
+	}
+
+	require.NotEmpty(t, d.CommandsByName("AddPoint"))
+	require.NotEmpty(t, d.CommandsByName("AddCircle"))
+	require.NotEmpty(t, d.CommandsByName("AddLine"))
+}
+
+func TestRender_PanTooLarge_FallsBackToFullRedraw(t *testing.T) {
+	t.Parallel()
+
+	w := NewWorld(10, 10)
+	w.resetGrid(2 * SCALE)
+
+	_, err := w.AddPoint(5, 5)
+	require.NoError(t, err)
+	for _, obj := range w.objects {
+		w.indexObject(obj)
+	}
+
+	params := RenderParams{
+		ViewportWidthPx:  10,
+		ViewportHeightPx: 10,
+		MarginXPx:        4, // threshold=2
+		MarginYPx:        4,
+		CameraXWorldFp:   5 * SCALE,
+		CameraYWorldFp:   5 * SCALE,
+		CameraZoom:       1.0,
+	}
+
+	d0 := &fakePrimitiveDrawer{}
+	require.NoError(t, w.Render(d0, params))
+
+	// Pan right by 3 units => abs(dx)=3 > threshold(2) => full redraw expected.
+	params2 := params
+	params2.CameraXWorldFp += 3 * SCALE
+
+	d := &fakePrimitiveDrawer{}
+	err = w.Render(d, params2)
+	require.NoError(t, err)
+
+	// Full redraw should NOT call CopyShift.
+	require.Empty(t, d.CommandsByName("CopyShift"))
+
+	// Should contain at least one reasonably wide clip.
+	clipCmds := d.CommandsByName("ClipRect")
+	require.NotEmpty(t, clipCmds)
+
+	foundWide := false
+	for _, c := range clipCmds {
+		if int(c.Args[2]) > 1 {
+			foundWide = true
+			break
+		}
+	}
+	require.True(t, foundWide)
+}