[Tutorial poll]

Unfortunately, there is no shortage of unappreciative jerks who think tutorial means "Make my game for me". I have really enjoyed your Project Saturn series. Being new to Leadwerks myself, it's been a great series to help me apply my existing knowledge to the Leadwerks workflow, I'd love to see the series continue.

 

I would also enjoy learning how to use C++ and Lua together.

[Write Buffer to file? (Taking a screenshot)]

Because digging through the source is not the same as documentation.

[Window/contex resize event?]

I tested this in App.lua, but it should work the same in the App.cpp. it does work.

 

Create a variable to store the window size

prevScreenSize = Vec2(0,0)

Get the initial window size in start

self.prevScreenSize = Vec2(Math:Round(self.window:GetWidth()), Math:Round(self.window:GetHeight()))

Check for change, update the variable when change is detected, and call a function

if self.prevScreenSize.x ~= Math:Round(self.window:GetWidth()) or self.prevScreenSize.y ~= Math:Round(self.window:GetHeight()) then
   self.prevScreenSize = Vec2(Math:Round(self.window:GetWidth()), Math:Round(self.window:GetHeight()))
   self:ScreenSizeChanged()
end

function App:ScreenSizeChanged()
   System:Print("ScreenSizeChanged: " .. self.prevScreenSize:ToString())
end

[Window/contex resize event?]

If there isn't a built in function, maybe store the window size in a variable in start, then compare that variable with the current window size and when it's different, update the variable with the current size and call a separate function. If getting the current window size is expensive, you could limit a check to every n iterations of the the loop.

 

Possibly use System::AddHook?

 

I'm not new to programming, but I am new to Leadwerks, so this may be a terrible idea.

[Why doesn't pickinfo.normal return -1, 0, or 1 only?]

In the example output above, the pick was from the -X side, it should have returned (-1,0,0). My test is using a grid aligned cube created in blender, it has a (0,0,0) rotation in the Leadwerks map. The problem does not exist when using a CSG, I am only able to create the problem with the Blender cube import. Interestingly, good values are returned from most of the face surface area from any face, but each face has a seemingly random spot that returns bad values. I have tried a default blender cube, which is off grid by default, with a center origin, a grid aligned blender cube with a center origin, and a grid aligned blender cube with a corner origin, they all produce the same result. I have no idea how a six sided cube can return different normal values from different areas of the same face.

[Why doesn't pickinfo.normal return -1, 0, or 1 only?]

Okay, I made a much simpler script to try to eliminate any other potential causes. It's still not returning clean -1, 0, 1 values, but rather fractions.

 

Script.player = nil --entity "Player"
Script.reticle = "" --path "Reticle" "Tex file (*.tex):tex;"
window = Window:GetCurrent()
world = World:GetCurrent()
context = Context:GetCurrent()
pickradius = 0.1
pickinfo = nil
mousePos = nil
reticleOptic = nil
function Script:Start()
   pickinfo = PickInfo()
   reticleOptic = Texture:Load(self.reticle)
end
function Script:UpdateWorld()
   mousePos = window:GetMousePosition()
   if (self.player.script.camera:Pick(mousePos.x, mousePos.y, pickinfo, pickradius, true)) then
    if pickinfo ~= nil then
	    if pickinfo.entity:GetKeyValue("name") == "Block" then
		    --System:Print("Entity: " .. pickinfo.entity:GetPosition():ToString())
		    --System:Print("Position: " .. pickinfo.position:ToString())
		    System:Print("Normal: " .. pickinfo.normal:ToString())
	    end
    end
   end
end
function Script:PostRender(context)
   if reticleOptic ~= nil then
    context:SetColor(1,1,1,1)
    context:SetBlendMode(Blend.Alpha)	   
    context:DrawImage(reticleOptic, context:GetWidth()/2-32, context:GetHeight()/2-32, 64, 64)
    context:SetBlendMode(Blend.Solid)
   end   
end

 

Normal: -0.968764, -0.175351, 0.175352

[Why doesn't pickinfo.normal return -1, 0, or 1 only?]

This is what I'm getting when camera picking the X face of a cube placed on the ground.

 

if (self.player.script.camera:Pick(mousePos.x, mousePos.y, pickinfo, pickradius, true)) then
   System:Print("Entity: " .. pickinfo.entity:GetPosition():ToString())
   System:Print("Position: " .. pickinfo.position:ToString())
   System:Print("Normal: " .. pickinfo.normal:ToString())
end

 

 

Entity: -3.000000, 1.000000, 0.000000

Position: -2.555588, 1.315765, -0.250583

Normal: 0.740685, 0.526274, -0.417638

[Why doesn't pickinfo.normal return -1, 0, or 1 only?]

Your right, they are correct, it looks like the pickinfo.normal is describing the exact hit position, which is great for adding an impact particle effect at the location a hit occurs, though I wish pickinfo also had a separate return value that simply described the side of the hit. Good for geometric shape placement

 

pickinfo.entity:GetPosition() + pickinfo.normal = exact hit position

[Why doesn't pickinfo.normal return -1, 0, or 1 only?]

Forgive me if this is a silly question, but my previous experience with collision normals is as follows:

 

collision on X should return Vec3(1,0,0)

collision on -X should return Vec3(-1,0,0)

collision on Y should return Vec3(0,1,0)

collision on -Y should return Vec3(0,-1,0)

collision on Z should return Vec3(0,0,1)

collision on -Z should return Vec3(0,0,-1)

 

Leadwerks pickinfo.normal returns a fraction depending on where on a face the collision occurs. Is pickinfo.face the "normal" function I'm used to, and maybe pickinfo.normal is describing the hit point?

 

If this is the case, how do you use pickinfo.face, I couldn't find much documentation on it?

 

Thanks!

[pickinfo.entity name and collision problem with prefabs]

I finally got everything working to some degree. It could use some more refinement, but this was just an API familiarization exercise for me.

 

Thanks everyone for you input and assistance.

 

Just in case anyone is interested in the basis of a Minecraft style block pick/placement script, here it is.

 

1. Create a one unit (meter?) cube in your favorite 3D app.

2. Import and save as a prefab.

3. Create a pivot, and attached this script to it, then parent the pivot to your FPSPlayer.

4. Link in the player, prefab, a pickup sound, a placement sound, and a texture reticle.

 

Left Ctrl = toggles in and out of block building mode

Right mouse click = places a block

Left mouse click = removes a block

 

Cheers!

 

EDIT:

Updated to fix some issues

 

Script.player = nil --entity "Player"
Script.blockPrefab = "" --path "Prefab" "Prefab (*.pfb):pfb"
Script.pickSound = "" --path "Pick Sound" "Sound File (*.wav):wav;Ogg Vorbis (*.ogg):ogg"
Script.placeSound = "" --path "Place Sound" "Sound File (*.wav):wav;Ogg Vorbis (*.ogg):ogg"
Script.reticle = "" --path "Reticle" "Tex file (*.tex):tex;"

window = Window:GetCurrent()
world = World:GetCurrent()
context = Context:GetCurrent()
pickradius = 0.1
block = nil
blockMode = false
pickinfo = nil
mousePos = nil
pickSnd = nil
placeSnd = nil
reticleOptic = nil


function Script:Start()
   pickinfo = PickInfo()
   pickinfoTest = PickInfo()
   pickSnd = Sound:Load(self.pickSound)
   placeSnd = Sound:Load(self.placeSound)
   reticleOptic = Texture:Load(self.reticle)
end


function Script:UpdateWorld()
   mousePos = window:GetMousePosition()

   -- Toggle blockMode
   if window:KeyHit(Key.ControlKey) then
       if blockMode == false then
           blockMode = true
       else
           blockMode = false
       end
   end

   -- blockMode
   if blockMode == true then
       -- Load a new block
       if block == nil then            
           block = Prefab:Load(self.blockPrefab)    
           block:SetPickMode(0) -- ignore        
           block:SetCollisionType(4)                
           block:SetKeyValue("name","Block")        
       end

       -- Position the block grid aligned and normal offset
       if block ~= nil then
           if (self.player.script.camera:Pick(mousePos.x, mousePos.y, pickinfo, pickradius, true)) then
               local blockPos = Vec3(Math:Round(pickinfo.position.x), 
                   Math:Round(pickinfo.position.y), 
                   Math:Round(pickinfo.position.z))

               block:SetPosition(blockPos, true)            
           end
       end

       -- Place the block
       if window:MouseHit(2) then -- right mouse button
           if placeSnd ~= nil then
               placeSnd:Play()
           end
           block:SetPickMode(2) -- Polygon
           block:SetCollisionType(2)
           block:SetShape(Shape:Box())
           block:SetRotation(Vec3(0,0,0), true)
           block = nil            
       end

       -- Release the block
       if window:MouseHit(1) then -- left mouse button
           if pickinfo.entity:GetKeyValue("name") == "Block" then
               System:Print("Release")
               pickinfo.entity:Release()
               if pickSnd ~= nil then
                   pickSnd:Play()
               end
           end

       end
   else -- Not in blockMode, release the block
       if block ~= nil then    
           block:Release()
           block = nil
       end
   end
end


function Script:PostRender(context)
   if reticleOptic ~= nil then
       context:SetColor(1,1,1,1)
       context:SetBlendMode(Blend.Alpha)        
       context:DrawImage(reticleOptic, context:GetWidth()/2-32, context:GetHeight()/2-32, 64, 64)
       context:SetBlendMode(Blend.Solid)
   end    
end

[pickinfo.entity name and collision problem with prefabs]

@shadmar - After you mentioned it, I started looking deeper into my prefab and the Leadwerks collision rules. I have made a little progress. I swapped my CSG block for a basic blender cube, and I'm now setting SetPickMode(0) and SetCollisionType(4) on the instantiated prefab so that it won't be picked while positioning for placement. I've adjusted my camera picks to use collision type to (2), and after I place a block I set SetPickMode(1) and SetCollisionType(2) so that it should be pickable again. Once a block is placed however, I can collide with it when walking up to it or jumping on top of it with the FPSPlayer, but I still can't camera pick the placed blocks. I have the exact same scenario using the CSG cube prefab after SetPickMode and SetCollisionType adjustments, the collider stops me from walking through it, but I can't pick it from the camera.

 

These pick failure are what I was perceiving as Key/Value failures. If I place an instance of my prefab in the scene at design time, I can pick it at runtime and read the Key/Value, but not when instantiated during runtime. I tried adding world:Update and world:Render() after block placement just in case some physics update was necessary, but it had no effect.

 

So it seems something must be required to commit pickmode and collisiontype changes at runtime, but I can't seem to figure out what.

 

The current state of my script:

Script.player = nil --entity "Player"

window = Window:GetCurrent()
world = World:GetCurrent()
context = Context:GetCurrent()
pickradius = 0.1
block = nil
blockMode = false
pickinfo = nil
mousePos = nil

function Script:Start()
   pickinfo = PickInfo()
end

function Script:UpdateWorld()
   mousePos = window:GetMousePosition()

   -- Toggle blockMode
   if window:KeyHit(Key.ControlKey) then
       if blockMode == false then
           blockMode = true
       else
           blockMode = false
       end
   end

   -- blockMode
   if blockMode == true then
       -- Load a new block
       if block == nil then
           block = Prefab:Load("Prefabs/CM/Cube.pfb")
           block:SetPickMode(0) -- ignore 
           block:SetCollisionType(4) 
           block:SetKeyValue("name","Block") 
       end

       -- Position the block grid aligned and normal offset
       if block ~= nil then
           if (self.player.script.camera:Pick(mousePos.x, mousePos.y, pickinfo, pickradius, true, 2)) then
               block:SetPosition(Vec3(math.floor(pickinfo.position.x), 
                   math.floor(pickinfo.position.y), 
                   math.floor(pickinfo.position.z)) + 
                   Vec3(pickinfo.normal.x, pickinfo.normal.y, pickinfo.normal.z)) 
           end
       end

       -- Place the block
       if window:MouseHit(2) then -- right mouse button
           block:SetPickMode(1) -- sphere
           block:SetCollisionType(2)
           block = nil
       end

       -- Debug
       if pickinfo ~= nil then
           if pickinfo.entity ~= nil then
               System:Print("pickinfo: " .. pickinfo.entity:GetKeyValue("name"))
           end
       end

       -- Release the block
       if window:MouseHit(1) then -- left mouse button
           if (self.player.script.camera:Pick(mousePos.x, mousePos.y, pickinfo, pickradius, true, 2)) then 
               if pickinfo.entity:GetKeyValue("name") == "Block" then
                   pickinfo.entity:Release()
               end
           end
       end
   else -- Not in blockMode, release the block
       if block ~= nil then 
           block:Release()
           block = nil
       end
   end
end

[pickinfo.entity name and collision problem with prefabs]

@Aggor - yes the GetKeyValue() with upper case "Name" was a test, I tried upper and lower, they both produce the same error.

 

@Haydenmango - Thanks, I'll try GetClass() and GetClassName() out.

 

@Guppy - This sounds great because it would allow me to categories everything, and in my case I really only need a bool check, but can you spot anything I'm doing wrong with the code above, and why it errors:

 

I instantiate the prefab, then set a key/value pair with name/Block

block = Prefab:Load("Prefabs/CM/Block.pfb")
block:SetKeyValue("name","Block")

 

then, in the pickinfo I'm attempting to read the key/value pair

System:Print(pickinfo.entity:GetKeyValue("name"))

 

But the Print is producing this error: argument #3 is 'string'; '[no object]' expected.

 

Thanks guys!

[pickinfo.entity name and collision problem with prefabs]

Let me ask about entity identification another way. If I have a collision with an entity, what is the best way to distinguish the entity from another? For example: instantiated blocks have the name "Block" and the ground the blocks sit on is a CSG with the name "Ground". If I want to Release() blocks, but not the ground, I need to check the collision entity to determine it's a block and to Release it, or if it's the ground and to ignore the collision. Should I use the name of the entity (how do I get this), does Leadwerks have a layer system that I can place items on and check if the collision entity is on that layer, or maybe place a script on the ignore items and check for the type?

 

Thanks

[Physics shapes for imported models]

Great! Thank you.

[Physics shapes for imported models]

I watched Josh's video importing the monster truck to have the shapes automatically generated, but I wasn't sure how that would work in blender since you can't have multiple items with the same name in blender. Unless Leadwerks is just ignoring iterative numbers after the [Collision] name.

 

I got this working using the above method, mostly just because I wanted to understand it a bit better, but I'll also try it the other way just to test the result.

 

Thanks!

[Physics shapes for imported models]

Ahhh, I found it. Right click your model from the Assets tab and select [Generate Shape].

[Physics shapes for imported models]

I have created a small building model in blender and included a very low polly version of it for use as a physics shape, but I can't figure out how to make a physics shape out of it in Leadwerks. [save as Shape] is greyed out in the scene browser when I try to right click on the mesh.

 

Any help is appreciated,

Mike

[pickinfo.entity name and collision problem with prefabs]

I'm familiarizing myself with Leadwerks and so I have a simple test map that lets me place block prefabs like Minecraft.

 

How can I retrieve the name from a pickinfo.entity?

 

I tried the following, but it throws an error in Print in the window:MouseDown(1) check: (argument #3 is 'string'; '[no object]' expected.)

function Script:UpdateWorld()
   if block == nil then
       block = Prefab:Load("Prefabs/CM/Block.pfb")
       block:SetKeyValue("name","Block")
       block:SetCollisionType(Collision.Prop)
   end

   local pickinfo = PickInfo()
   local mousePos = window:GetMousePosition()
   if (self.player.script.camera:Pick(mousePos.x, mousePos.y, pickinfo, pickradius, true)) then
       block:SetPosition(Vec3(math.floor(pickinfo.position.x),
           math.floor(pickinfo.position.y),
           math.floor(pickinfo.position.z)) +
           Vec3(pickinfo.normal.x, pickinfo.normal.y/2, pickinfo.normal.z))
   end

   if window:MouseDown(2) then -- Place the block
       block = nil
   end

   if window:MouseDown(1) then -- Delete the block
       if pickinfo ~= nil then
           if pickinfo.entity ~= nil then
               System:Print(pickinfo.entity:GetKeyValue("name"))
           end
           --if pickinfo.entity:GetKeyValue("Name") == "Block" then
           -- pickinfo.entity:Release()
           --end
       end
   end
end

 

The other issue I'm having is that the placed prefabs have no physics collision.

 

Thanks,

Mike

[Raycasting / Pick help]

Looks like my duplicated cube had a duplicate of the script and the Camera was not bound to the exposed entity property.

 

Removing the script on the second cube, and removing the Vec3 cleared the errors.

 

I moved my self.right setter to the Start function.

 

Thanks for helping, sorry for the Leadwerks noob mistakes!

[Raycasting / Pick help]

That solved the raycast problem, But I'm still having issues drawing the line for debugging. I'm getting an error with no error message on the following line:

local pos = self.camera:Project(Vec3(self.position)) 

 

I have the camera defined outside the function as:

Script.camera=Entity--Entity

And I linked the scene camera to this property in the editor.

[Raycasting / Pick help]

[self.right] is defined outside of the function as:

 

Script.right=Vec3(1, 0, 0)--Vec3

 

I found the problem, I had accidentally used a lowercase in the [pickInfo] variable in the Pick function. It's working now.

 

Thanks

[Raycasting / Pick help]

I'm trying to translate my raycasting experience in Unity and Blender GE to Leadwerks, but I'm having a hard time connecting the dots. My test scene includes one cube on the ground, and another cube next to the first (on X axis) and raised above the ground and above the height of the ground cube so that when the game starts, the raised cube falls next to the ground cube. I have a lua script attached to the ground cube and I'm trying to cast a ray from the ground cubes position to a position farther down the x axis so that the raised cube will intersect when it falls.

 

This is my code in the UpdateWorld function. I get an blank error window. I'm very inexperienced with Leadwerks, so I may be going about it all wrong, but this is what I've gathered from the docs.

 

Thanks for any help you can provide.

 

function Script:UpdateWorld()
self.position = self.entity:GetPosition()
self.right = Vec3(self.position.x + self.right.x, self.position.y, self.position.z);

local pickInfo = PickInfo()
local clear = true
local world = World:GetCurrent()
local context = Context:GetCurrent()

local pos = self.camera:Project(Vec3(self.position))
local pRight = self.camera:Project(Vec3(self.right))
context:DrawLine(pos.x, pos.y, pRight.x, pRight.y)

if (world:Pick(self.position, self.right, pickinfo, 0.0, true)) then
clear= false
end
end

[Steam and Linux confusion]

Leadwerks has Indie and Standard license. Both licenses cover both Linux and Windows. The Linux version for steam has not been released yet.

 

Thank You!

[Steam and Linux confusion]

Thanks, so is the Linux version the same license or a separate license?

[Steam and Linux confusion]

I bought the Steam Indie edition because I wanted to start learning the engine, but I ultimately want the C++ access that's included in SE, and I would like to run the Linux version once all the kinks are worked out. The Steam version is currently Windows only, is the Linux version headed for Steam and will my license grant me access to it when it becomes available? Can I add my Steam license to the Client Area on my leadwerks.com account page?

 

Thanks!