diff --git a/src/implicit.mesh.glsl b/src/implicit.mesh.glsl
index a48d7477b62809029470e74113e9e747a8664046..40019d29938983dc687478daf5016d0cb3356517 100644
--- a/src/implicit.mesh.glsl
+++ b/src/implicit.mesh.glsl
@@ -6,8 +6,8 @@
 #include "include.glsl"
 #include "intervals.glsl"
 
-layout(local_size_x=1,local_size_y=1,local_size_z=1)in;
-layout(triangles,max_vertices=64,max_primitives=162)out;
+layout(local_size_x=32,local_size_y=1,local_size_z=1)in;
+layout(triangles,max_vertices=256,max_primitives=192)out;
 
 layout(location=0)out VertexOutput
 {
@@ -47,45 +47,58 @@ void main()
         vec4(bounds[0],bounds[1],bounds[2],1.),
     };
     
-    SetMeshOutputsEXT(8,6);
+    //This can be optimised
+    SetMeshOutputsEXT(256,192);
     mat4 mvp=camera_uniforms.proj*camera_uniforms.view*pc.world;
+    uint vindex = gl_LocalInvocationID.x*8;
+    uint pindex = gl_LocalInvocationID.x*6;
+
+    //adjust scale and position
+    for (int i = 0; i<8; i++)
+    {
+        positions[i] *= vec4(0.25,0.25,0.25,1.);
+        positions[i].x += (bounds[0]-bounds[3])*0.25 * (mod(gl_LocalInvocationID.x,4.)-1.5);
+        positions[i].y += (bounds[1]-bounds[4])*0.25 * (mod(floor(gl_LocalInvocationID.x/4.),4.)-1.5);
+        positions[i].z += (bounds[2]-bounds[5])*0.25 * (floor(gl_LocalInvocationID.x/16.)-1.5+gl_WorkGroupID.z*2.);
+    }    
+
     //mat4 sw=pc.world;
-    gl_MeshVerticesEXT[0].gl_Position=mvp*(positions[0]);
-    gl_MeshVerticesEXT[1].gl_Position=mvp*(positions[1]);
-    gl_MeshVerticesEXT[2].gl_Position=mvp*(positions[2]);
-    gl_MeshVerticesEXT[3].gl_Position=mvp*(positions[3]);
-    gl_MeshVerticesEXT[4].gl_Position=mvp*(positions[4]);
-    gl_MeshVerticesEXT[5].gl_Position=mvp*(positions[5]);
-    gl_MeshVerticesEXT[6].gl_Position=mvp*(positions[6]);
-    gl_MeshVerticesEXT[7].gl_Position=mvp*(positions[7]);
-    vertexOutput[0].position=(positions[0]);
-    vertexOutput[1].position=(positions[1]);
-    vertexOutput[2].position=(positions[2]);
-    vertexOutput[3].position=(positions[3]);
-    vertexOutput[4].position=(positions[4]);
-    vertexOutput[5].position=(positions[5]);
-    vertexOutput[6].position=(positions[6]);
-    vertexOutput[7].position=(positions[7]);
+    gl_MeshVerticesEXT[vindex+0].gl_Position=mvp*(positions[0]);
+    gl_MeshVerticesEXT[vindex+1].gl_Position=mvp*(positions[1]);
+    gl_MeshVerticesEXT[vindex+2].gl_Position=mvp*(positions[2]);
+    gl_MeshVerticesEXT[vindex+3].gl_Position=mvp*(positions[3]);
+    gl_MeshVerticesEXT[vindex+4].gl_Position=mvp*(positions[4]);
+    gl_MeshVerticesEXT[vindex+5].gl_Position=mvp*(positions[5]);
+    gl_MeshVerticesEXT[vindex+6].gl_Position=mvp*(positions[6]);
+    gl_MeshVerticesEXT[vindex+7].gl_Position=mvp*(positions[7]);
+    vertexOutput[vindex+0].position=(positions[0]);
+    vertexOutput[vindex+1].position=(positions[1]);
+    vertexOutput[vindex+2].position=(positions[2]);
+    vertexOutput[vindex+3].position=(positions[3]);
+    vertexOutput[vindex+4].position=(positions[4]);
+    vertexOutput[vindex+5].position=(positions[5]);
+    vertexOutput[vindex+6].position=(positions[6]);
+    vertexOutput[vindex+7].position=(positions[7]);
     
     if(signingvec.x>0){
-        gl_PrimitiveTriangleIndicesEXT[gl_LocalInvocationIndex+0]=uvec3(4,5,6);
-        gl_PrimitiveTriangleIndicesEXT[gl_LocalInvocationIndex+1]=uvec3(5,6,7);
+        gl_PrimitiveTriangleIndicesEXT[pindex+0]=uvec3(4,5,6)+uvec3(vindex);
+        gl_PrimitiveTriangleIndicesEXT[pindex+1]=uvec3(5,6,7)+uvec3(vindex);
     }else{
-        gl_PrimitiveTriangleIndicesEXT[gl_LocalInvocationIndex+0]=uvec3(0,1,2);
-        gl_PrimitiveTriangleIndicesEXT[gl_LocalInvocationIndex+1]=uvec3(1,2,3);
+        gl_PrimitiveTriangleIndicesEXT[pindex+0]=uvec3(0,1,2)+uvec3(vindex);
+        gl_PrimitiveTriangleIndicesEXT[pindex+1]=uvec3(1,2,3)+uvec3(vindex);
     }
     if(signingvec.y>0){
-        gl_PrimitiveTriangleIndicesEXT[gl_LocalInvocationIndex+2]=uvec3(2,3,6);
-        gl_PrimitiveTriangleIndicesEXT[gl_LocalInvocationIndex+3]=uvec3(7,3,6);
+        gl_PrimitiveTriangleIndicesEXT[pindex+2]=uvec3(2,3,6)+uvec3(vindex);
+        gl_PrimitiveTriangleIndicesEXT[pindex+3]=uvec3(7,3,6)+uvec3(vindex);
     }else{
-        gl_PrimitiveTriangleIndicesEXT[gl_LocalInvocationIndex+2]=uvec3(0,1,4);
-        gl_PrimitiveTriangleIndicesEXT[gl_LocalInvocationIndex+3]=uvec3(5,1,4);
+        gl_PrimitiveTriangleIndicesEXT[pindex+2]=uvec3(0,1,4)+uvec3(vindex);
+        gl_PrimitiveTriangleIndicesEXT[pindex+3]=uvec3(5,1,4)+uvec3(vindex);
     }
     if(signingvec.z>0){
-        gl_PrimitiveTriangleIndicesEXT[gl_LocalInvocationIndex+4]=uvec3(1,3,5);
-        gl_PrimitiveTriangleIndicesEXT[gl_LocalInvocationIndex+5]=uvec3(3,5,7);
+        gl_PrimitiveTriangleIndicesEXT[pindex+4]=uvec3(1,3,5)+uvec3(vindex);
+        gl_PrimitiveTriangleIndicesEXT[pindex+5]=uvec3(3,5,7)+uvec3(vindex);
     }else{
-        gl_PrimitiveTriangleIndicesEXT[gl_LocalInvocationIndex+4]=uvec3(0,2,4);
-        gl_PrimitiveTriangleIndicesEXT[gl_LocalInvocationIndex+5]=uvec3(2,4,6);
+        gl_PrimitiveTriangleIndicesEXT[pindex+4]=uvec3(0,2,4)+uvec3(vindex);
+        gl_PrimitiveTriangleIndicesEXT[pindex+5]=uvec3(2,4,6)+uvec3(vindex);
     }
 }
\ No newline at end of file
diff --git a/src/intervals.glsl b/src/intervals.glsl
index 7854ea7e31b8a1323c2bba1dd48f437390d3ad32..6ac13871257226453e41b505adee70401fe7b8c6 100644
--- a/src/intervals.glsl
+++ b/src/intervals.glsl
@@ -6,6 +6,7 @@
 #include "instructionset.glsl"
 
 const float INFINITY = 1. / 0.;
+const float NINFINITY = (-1.) / 0.;
 
 struct Description{
     uint scene;
@@ -16,6 +17,7 @@ struct Description{
     uint mat2s;
     uint mat3s;
     uint mat4s;
+    uint dependencies;
 };
 
 layout(set=0,binding=2)restrict readonly buffer SceneDescription{
@@ -49,6 +51,9 @@ layout(set=0,binding=10)restrict readonly buffer Mat4Const{
 layout(set=0,binding=11)restrict readonly buffer MatConst{
     mat4 mats[];
 }matconst;
+layout(set=0,binding=12)restrict readonly buffer DepInfo{
+    uint8_t dependencies[2][];
+}depinfo;
 
 // unpack integers
 #define get_caches u32vec4 major_unpack=scenes.opcodes[major_position+desc.scene];\
@@ -548,10 +553,28 @@ void default_mask()
     in1[1]=trunc(in1[1]);\
 }
 
+Description desc;
+
+void pruneall (uint8_t pos) {
+    uint8_t[2] deps;
+    for (int i = 0; i < pos; i++)
+    {
+        deps = depinfo.dependencies[desc.dependencies+i];
+        if (deps[1] != 255) {
+            //this is a dual output function (dup)
+            //todo
+        }
+        else if (deps[0] == pos) {
+            pruneall(i);
+        }
+    }
+    mask[pos>>3] &= ~(1<<(pos&7));
+}
+
 #ifdef debug
-vec3 scene(vec3 p[2])
+vec3 scene(vec3 p[2], bool prune)
 #else
-float[2]scene(vec3 p[2])
+float[2]scene(vec3 p[2], bool prune)
 #endif
 {
     uint major_position=0;
@@ -559,7 +582,7 @@ float[2]scene(vec3 p[2])
     
     uint minor_integer_cache[8];
 
-    Description desc = scene_description.desc[gl_GlobalInvocationID.x];
+    desc = scene_description.desc[gl_GlobalInvocationID.x];
     
     clear_stacks();
     push_vec3(p);
@@ -1219,7 +1242,7 @@ float[2]scene(vec3 p[2])
                         float[2]in1=pull_float(ifconst(0));
                         if (floor((in1[0]/PI)) == floor((in1[1]/PI)))
                         {
-                            in1[0] = -INFINITY;
+                            in1[0] = NINFINITY;
                             in1[1] = INFINITY;
                         }
                         else {
diff --git a/src/main.rs b/src/main.rs
index fc12d58fc03467084f07f76f7656cedc4ba9f869..e8ba4cd810f582b359f14b88f95be9a860123255 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -602,12 +602,12 @@ fn main() {
                 let mut data = [[0u32; 4]; 29];
 
                 let parts = vec![
-                    CSGPart::opcode(InstructionSet::OPDupVec3, 0b000000),
-                    CSGPart::opcode(InstructionSet::OPSubVec3Vec3, 0b010000),
+                    //CSGPart::opcode(InstructionSet::OPDupVec3, 0b000000),
+                    //CSGPart::opcode(InstructionSet::OPSubVec3Vec3, 0b010000),
                     CSGPart::opcode(InstructionSet::OPSDFSphere, 0b100000),
-                    CSGPart::opcode(InstructionSet::OPAddVec3Vec3, 0b010000),
-                    CSGPart::opcode(InstructionSet::OPSDFSphere, 0b100000),
-                    CSGPart::opcode(InstructionSet::OPSmoothMinFloat, 0b000000),
+                    //CSGPart::opcode(InstructionSet::OPAddVec3Vec3, 0b010000),
+                    //CSGPart::opcode(InstructionSet::OPSDFSphere, 0b100000),
+                    //CSGPart::opcode(InstructionSet::OPSmoothMinFloat, 0b000000),
                     CSGPart::opcode(InstructionSet::OPStop, 0b000000),
                 ];
 
@@ -828,7 +828,7 @@ fn main() {
                         .into();
                     builder
                         .push_constants(implicit_pipeline.layout().clone(), 0, push_constants)
-                        .draw_mesh([1, 1, 1])
+                        .draw_mesh([1, 1, 2])
                         .unwrap();
                 }