v0.1.0 initial commit

render/scan.go

@@ -0,0 +1,32 @@
+package render
+
+import (
+	"symph/game"
+	"symph/parameter"
+)
+
+// GridScan caches one frame of per-position lookahead and resolves the
+// grid-wide nearest distances. Blink membership is a grid-scope property, so
+// every position is scanned before any tile is drawn. Allocation-free: fixed
+// arrays refilled in place, shared by both frontends
+type GridScan struct {
+	Tiles   [parameter.GamePlayIndexYMax][parameter.GamePlayIndexXMax]game.TileLookahead
+	NearPos int // grid-wide nearest positive distance; -1 when none
+	NearNeg int // grid-wide nearest negative distance; -1 when none
+}
+
+func (g *GridScan) Refresh(s *game.GameState) {
+	g.NearPos, g.NearNeg = -1, -1
+	for y := range parameter.GamePlayIndexYMax {
+		for x := range parameter.GamePlayIndexXMax {
+			tl := s.ScanTile(y, x, parameter.PositionLookaheadWindow)
+			g.Tiles[y][x] = tl
+			if d := tl.Positive.Distance; d >= 0 && (g.NearPos < 0 || d < g.NearPos) {
+				g.NearPos = d
+			}
+			if d := tl.Negative.Distance; d >= 0 && (g.NearNeg < 0 || d < g.NearNeg) {
+				g.NearNeg = d
+			}
+		}
+	}
+}