room changes

world.lua

@@ -963,20 +963,61 @@ function World:drawRoomNeighborhood(room)
 	local transform = self:roomNeighborhoodTransform(room)
 	if not transform then return end
 	self.drawingRoomNeighborhood = true
+	local currentChannels = room:getRenderChannels()
+	local roomWidth, roomHeight = width * transform.zoom, height * transform.zoom
+
+	local function drawAt(offsetX, offsetY, level, channels)
+		love.graphics.push()
+		love.graphics.translate(transform.originX + (offsetX + transform.cameraX) * roomWidth,
+			transform.originY + (offsetY + transform.cameraY) * roomHeight)
+		love.graphics.scale(transform.zoom, transform.zoom)
+		level:draw(channels)
+		love.graphics.pop()
+	end
+
 	for roomY = -1, 1 do
 		for roomX = -1, 1 do
 			local name = self:roomAt(transform.location.x + roomX, transform.location.y + roomY)
 			local adjacent = name and self.levels[name]
 			if adjacent then
-				love.graphics.push()
-				love.graphics.translate(transform.originX + (roomX + transform.cameraX) * width * transform.zoom,
-					transform.originY + (roomY + transform.cameraY) * height * transform.zoom)
-				love.graphics.scale(transform.zoom, transform.zoom)
-				adjacent:draw()
-				love.graphics.pop()
+				drawAt(roomX, roomY, adjacent)
 			end
 		end
 	end
+
+	-- Each cardinal neighbour receives a second, real render through the active
+	-- colours in the current room. The shader only chooses a wispy portion of
+	-- the shared visible margin, preserving all literal RGB passes and sprites.
+	if porousRoomCanvas and porousRoomBoundaryShader and #currentChannels > 0 then
+		local targetCanvas = love.graphics.getCanvas()
+		local directions = {
+			{ x = -1, y = 0 }, { x = 1, y = 0 }, { x = 0, y = -1 }, { x = 0, y = 1 },
+		}
+		for _, direction in ipairs(directions) do
+			local name = self:roomAt(transform.location.x + direction.x, transform.location.y + direction.y)
+			local adjacent = name and self.levels[name]
+			if adjacent then
+				love.graphics.setCanvas(porousRoomCanvas)
+				love.graphics.clear(0, 0, 0, 0)
+				drawAt(direction.x, direction.y, adjacent, currentChannels)
+
+				love.graphics.setCanvas(targetCanvas)
+				local roomLeft = transform.originX + (direction.x + transform.cameraX) * roomWidth
+				local roomTop = transform.originY + (direction.y + transform.cameraY) * roomHeight
+				porousRoomBoundaryShader:send("porousTime", love.timer.getTime())
+				porousRoomBoundaryShader:send("porousRoomRect", {roomLeft, roomTop, roomWidth, roomHeight})
+				porousRoomBoundaryShader:send("porousDirection", {direction.x, direction.y})
+				-- Exactly the amount of the neighbour exposed by the zoom-out.
+				porousRoomBoundaryShader:send("porousDepth", (1 - transform.zoom) * width / 2)
+				love.graphics.setBlendMode("alpha")
+				love.graphics.setColor(1, 1, 1, 1)
+				love.graphics.setShader(porousRoomBoundaryShader)
+				love.graphics.draw(porousRoomCanvas, 0, 0)
+				love.graphics.setShader()
+			end
+		end
+		love.graphics.setBlendMode("screen")
+	end
 	self.drawingRoomNeighborhood = false
 end