Converting meshes to models

Codea Craft
61

@Bri_G I was getting that when I first started, that’s where I gave up. I’ll have to look at what I included and where I got it from.

62

@dave1707 glad it works now. The @LoopSpace code is very complete, but dont ask me to explain it! By the way his sphere wraps a texture correctly, unlike the native codea sphere.

63

@Bri_G Try using this PseudoMesh class instead of the one at the beginning of the discussion. Let me know if this works.

PseudoMesh = class()

function PseudoMesh:init()
    self.vertices = {}
    self.texCoords = {}
    self.normals = {}
    self.colors = {}
    self.size = 0
end

function PseudoMesh:vertex(k,v)
    if v then
        self.vertices[k] = v
    else
        return self.vertices[k]
    end
end

function PseudoMesh:normal(k,v)
    if v then
        self.normals[k] = v
    else
        return self.normals[k]
    end
end

function PseudoMesh:texCoord(k,v)
    if v then
        self.texCoords[k] = v
    else
        return self.texCoords[k]
    end
end

function PseudoMesh:color(k,v)
    if v then
        self.colors[k] = v
    else
        return self.colors[k]
    end
end

function PseudoMesh:setColors(c)
    for k=1,self.size do
        self.colors[k] = c
    end
end

function PseudoMesh:resize(k)
    self.size = k
end

local mm = getmetatable(mesh())

function PseudoMesh:addJewel(t)
    return mm.addJewel(self,t)
end

function PseudoMesh:addPyramid(t)
    return mm.addPyramid(self,t)
end

function PseudoMesh:addPolygon(t)
    return mm.addPolygon(self,t)
end

function PseudoMesh:addCone(t)
    return mm.addCone(self,t)
end

function PseudoMesh:addBlock(t)
    return mm.addBlock(self,t)
end

function PseudoMesh:addCylinder(t)
    return mm.addCylinder(self,t)
end

function PseudoMesh:addSphere(t)
    return mm.addSphere(self,t)
end

function PseudoMesh:addSphereSegment(t)
    return mm.addSphereSegment(self,t)
end

function PseudoMesh:invertNormals()
    for k,v in ipairs(self.normals) do
        self.normals[k] = -v
    end
end


function PseudoMesh:toModel()
    local m = craft.model()
    local i = {}
    local n = #self.vertices
    for k=1,n,3 do
        if (self.vertices[k+1] - self.vertices[k]):cross(self.vertices[k+2] - self.vertices[k]):dot(self.normals[k+1] + self.normals[k+2] + self.normals[k]) < 0 then
            table.insert(i,k)
            table.insert(i,k+1)
            table.insert(i,k+2)
        else
            table.insert(i,k)
            table.insert(i,k+2)
            table.insert(i,k+1)
        end
    end
    m.positions = self.vertices
    m.normals = self.normals
    m.uvs = self.texCoords
    m.colors = self.colors
    m.indices = i
    return m
end

function extendModel()

    local mt = getmetatable(craft.model)
    if mt.__extended then
        return true
    end

    local mm = getmetatable(mesh())
    if not mm.__extended then
        return false
    end

    rawset(mt,"jewel", function(t)
        local m = PseudoMesh()
        mm.addJewel(m,t)
        return m:toModel()
    end)
    
    rawset(mt,"pyramid", function(t)
        local m = PseudoMesh()
        mm.addPyramid(m,t)
        return m:toModel()
    end)
    
    rawset(mt,"polygon", function(t)
        local m = PseudoMesh()
        mm.addPolygon(m,t)
        return m:toModel()
    end)
    
    rawset(mt,"block", function(t)
        local m = PseudoMesh()
        mm.addBlock(m,t)
        return m:toModel()
    end)

    rawset(mt,"cylinder", function(t)
        local m = PseudoMesh()
        mm.addCylinder(m,t)
        return m:toModel()
    end)

    rawset(mt,"sphere", function(t)
        local m = PseudoMesh()
        mm.addSphere(m,t)
        return m:toModel()
    end)

    rawset(mt,"sphereSegment", function(t)
        local m = PseudoMesh()
        mm.addSphereSegment(m,t)
        return m:toModel()
    end)

    rawset(mt.___class,"append", function(s,m,o)
        o = o or vec3(0,0,0)
        local nv = s.vertexCount
        local ni = s.indexCount
        local n = m.size
        s:resizeVertices(nv+n)
        s:resizeIndices(ni+n)
        local i = {}
        for k=1,n,3 do
            if (m.vertices[k+1] - m.vertices[k]):cross(m.vertices[k+2] - m.vertices[k]):dot(m.normals[k+1] + m.normals[k+2] + m.normals[k]) < 0 then
                table.insert(i,k)
                table.insert(i,k+1)
                table.insert(i,k+2)
            else
                table.insert(i,k)
                table.insert(i,k+2)
                table.insert(i,k+1)
            end
        end
        for k=1,n do
            s:position(nv+k,m.vertices[k]+o)
            s:normal(nv+k,m.normals[k])
            s:color(nv+k,m.colors[k])
            s:uv(nv+k,m.texCoords[k])
            s:addElement(i[k])
        end
    end)

    rawset(mt,"__extended",true)
    return true
end

local exports = {
    extendModel = extendModel
}
64

@dave1707 - with dependencies that works - now to try and understand code. Thanks.

65

@Bri_G There a lot of code there, over 2000 lines. Maybe once you understand a small section of it, the rest is just a repeat for the different objects.

66

@dave1707 - yup, picked up on that. Thankfully @Loopspace has written copious notes in some of his code which helps.

67

Latest versions of my code can be found on github. I use them a fair bit so I do try to fix bugs as I encounter them, and add new stuff when I think it’s useful. I’ve added that link to the opening post so it’s easier to find.

Happy to answer questions about it!

68

@LoopSpace - thanks for the update, I lose track of where all the valuable resources are.