From b193e85a38e20ed65f6b4914c0be60eadec2cf6e Mon Sep 17 00:00:00 2001
From: SimonDanisch <sdanisch@gmail.com>
Date: Sun, 29 Nov 2015 14:36:59 +0100
Subject: [PATCH] added rounded cube mesh, not working yet

---
 src/primitives.jl | 52 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 52 insertions(+)

diff --git a/src/primitives.jl b/src/primitives.jl
index 50e1516..942c393 100644
--- a/src/primitives.jl
+++ b/src/primitives.jl
@@ -89,3 +89,55 @@ function call{MT <: AbstractMesh}(::Type{MT}, s::Sphere, facets=12)
     end
     MT(vertices, indexes)
 end
+
+
+signedpower(v, n) = sign(v)*abs(v)^n
+
+immutable RoundedCube{T}
+    power::T
+end
+export RoundedCube
+function call{M <: AbstractMesh}(::Type{M}, c::RoundedCube, N=128)
+    (N < 3) && error("Usage: $N nres rpower\n")
+    # Create vertices
+    L = (N+1)*(N÷2+1)
+    has_texturecoordinates = true
+    p = Array(vertextype(M), L)
+    texture_coords = Array(UV{Float32}, L)
+    faces = Array(facetype(M), N*2)
+    NH = N÷2
+    # Pole is along the z axis
+    for j=0:NH
+        for i=0:N
+            index = j * (N+1) + i
+            theta = i * 2 * pi / N
+            phi   = -0.5*pi + pi * j / NH
+            # Unit sphere, power determines roundness
+            x,y,z = (
+                signedpower(cos(phi), c.power) * signedpower(cos(theta), c.power),
+                signedpower(cos(phi), c.power) * signedpower(sin(theta), c.power),
+                signedpower(sin(phi), c.power)
+            )
+            if has_texturecoordinates
+                u = abs(atan2(y,x) / (2*pi))
+                texture_coords[index+1] = (u, 0.5 + atan2(z, sqrt(x*x+y*y)) / pi)
+            end
+            # Seams
+            if j == 0;  x,y,z = 1,1,2; end
+            if j == NH; x,y,z = 1,1,0; end
+            if i == N;  x,y   = p[(j*(N+1)+i-N)+1]; end
+            p[index+1] = (1-x,1-y,1-z)
+        end
+    end
+    for j=0:(NH-1)
+        for i=0:(N-1)
+            i1 =  j    * (N+1) + i
+            i2 =  j    * (N+1) + (i + 1)
+            i3 = (j+1) * (N+1) + (i + 1)
+            i4 = (j+1) * (N+1) + i
+            faces[i*2+1] = (i1,i3,i4)
+            faces[i*2+2] = (i1,i2,i3)
+        end
+    end
+    M(p, faces)
+end