Add convex primitive

lua/primitive/core/construct.lua

@@ -3279,3 +3279,26 @@ registerType( "ladder", function( param, data, threaded, physics )
     return model
 end )
 
+
+-- CONVEX_HULL: hands raw points to PhysicsInitMultiConvex and leaves .index empty;
+-- convex_hull.lua re-triangulates the render mesh from the physics engine's own hull once it exists.
+registerType( "convex_hull", function( param, data, threaded, physics )
+    local model = simpleton.New()
+
+    local count = math_clamp( math_floor( tonumber( param.PrimPOINTS ) or 6 ), 4, 10 )
+
+    for i = 1, count do
+        local x = tonumber( param[ "PrimPX" .. i ] ) or 0
+        local y = tonumber( param[ "PrimPY" .. i ] ) or 0
+        local z = tonumber( param[ "PrimPZ" .. i ] ) or 0
+
+        model:PushXYZ( x, y, z )
+    end
+
+    if physics then model.convexes = { model.verts } end
+
+    util_Transform( model.verts, param.PrimMESHROT, param.PrimMESHPOS, threaded )
+
+    return model
+end )
+

lua/primitive/entities/convex_hull.lua

@@ -0,0 +1,132 @@
+
+-- PROTOTYPE: a convex volume from a vertex count (4-10) and free XYZ per vertex; the render mesh is rebuilt from the physics engine's own computed hull.
+
+do
+    local class = {}
+
+    -- Alternates Z so the default ring isn't coplanar (a flat ring is a degenerate zero-volume convex).
+    local function ringDefault( i, n )
+        local a = ( math.pi * 2 / n ) * ( i - 1 )
+        local z = ( i % 2 == 0 ) and 24 or -24
+        return Vector( math.cos( a ) * 48, math.sin( a ) * 48, z )
+    end
+
+    -- Sets keys.skip_tris since there's nothing to triangulate until physics exists (see SetRenderMesh).
+    function class:PrimitiveGetConstruct()
+        local keys = self:PrimitiveGetKeys()
+        keys.skip_tris = true
+
+        local clips = ImprovedClipping and ImprovedClipping.GetClips( self )
+        local valid, result = Primitive.construct.get( "convex_hull", keys, CLIENT, keys.PrimMESHPHYS, clips )
+
+        self.ImprovedClippingAllowSeal = not ( istable( result ) and result.multiConvex )
+
+        return valid, result
+    end
+
+
+    if CLIENT then
+        function class:SetRenderMesh( result )
+            if istable( result ) and not result.error then
+                local physobj = self:GetPhysicsObject()
+
+                if physobj:IsValid() then
+                    local convexes = physobj:GetMeshConvexes()
+
+                    if istable( convexes ) then
+                        local verts, index = {}, {}
+
+                        -- Swap the last two verts of each triangle to match Build()'s winding, or the hull renders inside-out.
+                        for i = 1, #convexes do
+                            local convex = convexes[i]
+
+                            for j = 1, #convex, 3 do
+                                local a = #verts + 1
+
+                                verts[a] = Vector( convex[j].pos )
+                                verts[a + 1] = Vector( convex[j + 1].pos )
+                                verts[a + 2] = Vector( convex[j + 2].pos )
+
+                                index[#index + 1] = a
+                                index[#index + 1] = a + 2
+                                index[#index + 1] = a + 1
+                            end
+                        end
+
+                        if #index >= 3 then
+                            result.verts = verts
+                            result.index = index
+
+                            result:Build( self:PrimitiveGetKeys(), false, true )
+                        end
+                    end
+                end
+            end
+
+            self.BaseClass.SetRenderMesh( self, result )
+        end
+    end
+
+
+    function class:PrimitiveOnSetup( initial, args )
+        if initial and SERVER then
+            duplicator.StoreEntityModifier( self, "mass", { Mass = 100 } )
+        end
+
+        self:SetPrimPOINTS( 6 )
+
+        for i = 1, 10 do
+            local p = ringDefault( i, 10 )
+
+            self[ "SetPrimPX" .. i ]( self, p.x )
+            self[ "SetPrimPY" .. i ]( self, p.y )
+            self[ "SetPrimPZ" .. i ]( self, p.z )
+        end
+
+        self:SetPrimMESHPHYS( true )
+    end
+
+
+    function class:PrimitiveSetupDataTables()
+        self:PrimitiveVar( "PrimPOINTS", "Int", { category = "hull", title = "point count", panel = "int", min = 4, max = 10 }, true )
+
+        for i = 1, 10 do
+            self:PrimitiveVar( "PrimPX" .. i, "Float", { category = "points", subcategory = "point " .. i, title = "point " .. i .. " x", panel = "float", min = -1000, max = 1000 }, true )
+            self:PrimitiveVar( "PrimPY" .. i, "Float", { category = "points", subcategory = "point " .. i, title = "point " .. i .. " y", panel = "float", min = -1000, max = 1000 }, true )
+            self:PrimitiveVar( "PrimPZ" .. i, "Float", { category = "points", subcategory = "point " .. i, title = "point " .. i .. " z", panel = "float", min = -1000, max = 1000 }, true )
+        end
+    end
+
+
+    local spawnlist
+    if CLIENT then
+        spawnlist = {
+            { category = "shapes_extra", entity = "primitive_convex_hull", title = "convex hull", command = "" },
+        }
+
+        local callbacks = {
+            EDITOR_OPEN = function( self, editor, name, val )
+                for k, cat in pairs( editor.categories ) do
+                    if k == "debug" or k == "mesh" or k == "model" then cat:ExpandRecurse( false ) else cat:ExpandRecurse( true ) end
+                end
+            end,
+
+            PrimPOINTS = function( self, editor, name, val )
+                for i = 1, 10 do
+                    local visible = i <= val
+
+                    for _, axis in ipairs( { "X", "Y", "Z" } ) do
+                        local row = editor.rows[ "PrimP" .. axis .. i ]
+                        if row then row:SetVisible( visible ) end
+                    end
+                end
+            end,
+        }
+
+        function class:EditorCallback( editor, name, val )
+            if callbacks[name] then callbacks[name]( self, editor, name, val ) end
+        end
+    end
+
+    Primitive.funcs.registerClass( "convex_hull", class, spawnlist )
+end