feat: add CheckShapeCollision()

game/collision.go

@@ -0,0 +1,21 @@
+package game
+
+import "tetris/engine/core"
+
+func CheckShapeCollision(pos core.Vec2i8, shape *Shape, grid *Grid) bool {
+	for _, block := range shape.Coordinates() {
+		block = pos.Add(block)
+
+		// Can't collide if block is above the grid.
+		if block.Y < 0 {
+			continue
+		}
+
+		// Check if the block collides with the bottom of the grid.
+		if block.Y >= int8(grid.Height()) {
+			return true
+		}
+	}
+
+	return false
+}