From 2c593fa96845d23dddce3107fff66e181d4794e3 Mon Sep 17 00:00:00 2001
From: Josh Holtrop <jholtrop+hg@gmail.com>
Date: Thu, 18 Nov 2010 08:54:29 -0500
Subject: [PATCH] grid picking in place

---
 anaglymtd.lua | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/anaglymtd.lua b/anaglymtd.lua
index 1d4d641..37d2ca9 100644
--- a/anaglymtd.lua
+++ b/anaglymtd.lua
@@ -1,6 +1,8 @@
 
 ag.import("std")
 
+td = {mx = 0, my = 0, picking = false}
+
 function init_event()
     ground = std.createPlanePointNormal(0, 0, 0, 0, 0, 1)
     ground:setColor(0, 1, 0)
@@ -11,7 +13,15 @@ function init_event()
     grid:setTexture(grid_texture)
     grid:setOffset(1)
 
+    grid_selector = ag.createQuad(0, 0, 0, 0.5, 0, 0, 0, 0.5, 0)
+    grid_selector:setVisible(false)
+    grid_selector:setColor(0, 0, 1, 0.5)
+    grid_selector:setBlending(true)
+    grid_selector:setOffset(2)
+
     ag.setCamera(2, -12, 10)
+
+    ag.setCursorVisible(true)
 end
 
 function key_down_event(k)
@@ -19,3 +29,23 @@ function key_down_event(k)
         ag.exit()
     end
 end
+
+function update_event()
+    hit = ag.pickOne(td.mx, td.my, ground)
+    if (hit) then
+        local px = ground.pick_pos[1]
+        local py = ground.pick_pos[2]
+        local x_coord = math.floor(px + 8)
+        local y_coord = math.floor(py + 8)
+        td.picking = (x_coord >= 0 and x_coord <= 15 and y_coord >= 0 and y_coord <= 15)
+        if (td.picking) then
+            grid_selector:setPosition(x_coord - 7.5, y_coord - 7.5, 0)
+        end
+    end
+    grid_selector:setVisible(td.picking)
+end
+
+function mouse_motion_event(x, y)
+    td.mx = x
+    td.my = y
+end