Use context-based renaming when minifying multiple files

Checker/compression_test.fs

@@ -56,7 +56,7 @@ let compressionTest args files =
         out.ToString().ToCharArray()
 
     let pointer = &&minified.[0]
-    log "%-40s " (match files with [f] -> f | f::_ -> f + "...")
+    log "%-40s " (match files with [f] -> f | f::_ -> f + "..." | [] -> "?")
     log "%5d " minified.Length
     let compressedSize = Crinkler.ApproximateModels4k(pointer, minified.Length)
     log "=> %8.3f\n" compressedSize

src/renamer.fs

@@ -157,6 +157,17 @@ module private RenamerImpl =
                 d.[id.OldName] <- newName
                 env.Rename(id, newName)
 
+    // Renaming safe across multiple files (e.g. uniform/in/out variables are
+    // renamed in a consistent way) that tries to optimize based on the context
+    // and variable reuse.
+    let multiFileRenaming contextTable (exportRenames: IDictionary<string, string>) (env: Env) (id: Ident) =
+        match exportRenames.TryGetValue(id.Name) with
+            | true, newName -> env.Rename(id, newName)
+            | false, _ ->
+                let cid = char (1000 + int id.Name)
+                let newName = chooseIdent contextTable cid env.availableNames
+                env.Rename(id, newName)
+
     let dontRename (env: Env) (id: Ident) =
         env.Rename(id, id.Name)
 
@@ -376,7 +387,10 @@ module private RenamerImpl =
 
         let mutable env =
             if Array.length shaders > 1 then
-                Env.Create(names, true, bijectiveRenaming names, shadowVariables)
+                // Env.Create(names, true, bijectiveRenaming names, shadowVariables)
+                let exportsRenames = Seq.zip [for export in exportedNames -> export.name] names |> dict
+                let contextTable = computeContextTable text
+                Env.Create(names, true, multiFileRenaming contextTable exportsRenames, shadowVariables)
             else
                 let contextTable = computeContextTable text
                 Env.Create(names, true, optimizeContext contextTable, shadowVariables)

tests/compression_results.log

@@ -1,4 +1,4 @@
-clod.frag...                              9414 => 1697.174
+clod.frag...                              8960 => 1549.730
 audio-flight-v2.frag                      4650 =>  904.201
 buoy.frag                                 4239 =>  629.709
 controllable-machinery.frag               7773 => 1230.829
@@ -20,4 +20,4 @@ terrarium.frag                            3634 =>  749.630
 the_real_party_is_in_your_pocket.frag    12248 => 1815.725
 valley_ball.glsl                          4386 =>  888.815
 yx_long_way_from_home.frag                3030 =>  615.535
-Total: 119757 => 21535.071
+Total: 119303 => 21387.626

tests/unit/inout.expected

@@ -1,64 +1,64 @@
 /* File generated with 
  * http://www.ctrl-alt-test.fr
  */
-# define VAR_ambientLight "m"
-# define VAR_diffuseColor "i"
-# define VAR_emissiveColor "a"
-# define VAR_fragmentColor "o"
-# define VAR_mediumDensity "t"
-# define VAR_normal "c"
-# define VAR_specularColor "n"
-# define VAR_texture0 "e"
-# define VAR_viewVec "v"
+# define VAR_ambientLight "f"
+# define VAR_diffuseColor "n"
+# define VAR_emissiveColor "z"
+# define VAR_fragmentColor "r"
+# define VAR_mediumDensity "s"
+# define VAR_normal "m"
+# define VAR_specularColor "e"
+# define VAR_texture0 "v"
+# define VAR_viewVec "d"
 
 // tests/unit/inout.frag
 "#version 330\n"
- "uniform samplerCube e;"
- "in vec3 c,v;"
- "out vec4 o;"
+ "uniform samplerCube v;"
+ "in vec3 m,d;"
+ "out vec4 r;"
  "void main()"
  "{"
-   "vec3 l=normalize(v),u=normalize(c),f=vec3(.1,.2,.3),x=texture(e,reflect(-l,u)).xyz,p=texture(e,refract(-l,u,1./1.5)).xyz,z=mix(f*p,x,.1);"
-   "o=vec4(z,1);"
+   "vec3 f=normalize(d),z=normalize(m),c=vec3(.1,.2,.3),n=texture(v,reflect(-f,z)).xyz,e=texture(v,refract(-f,z,1./1.5)).xyz,p=mix(c*e,n,.1);"
+   "r=vec4(p,1);"
  "}"
- "vec3 r(vec3 d,vec3 l,vec3 s)"
+ "vec3 t(vec3 v,vec3 m,vec3 f)"
  "{"
-   "float C=1.-clamp(dot(l,s),0.,1.);"
-   "return C*C*C*C*C*(1.-d)+d;"
+   "float r=1.-clamp(dot(m,f),0.,1.);"
+   "return r*r*r*r*r*(1.-v)+v;"
  "}"
- "vec3 r(vec3 l,vec3 y,vec3 u,vec3 f,vec3 d,float w)"
+ "vec3 t(vec3 v,vec3 m,vec3 f,vec3 n,vec3 d,float r)"
  "{"
-   "vec3 s=normalize(l+y),b,Z,Y;"
-   "float X=1.+2048.*(1.-w)*(1.-w);"
-   "b=f;"
-   "Z=vec3(pow(clamp(dot(s,u),0.,1.),X)*(X+4.)/8.);"
-   "Y=r(d,l,s);"
-   "return mix(b,Z,Y);"
+   "vec3 z=normalize(v+m),p,e,c;"
+   "float s=1.+2048.*(1.-r)*(1.-r);"
+   "p=n;"
+   "e=vec3(pow(clamp(dot(z,f),0.,1.),s)*(s+4.)/8.);"
+   "c=t(d,v,z);"
+   "return mix(p,e,c);"
  "}",
 
 // tests/unit/inout2.frag
 "#version 330\n"
- "uniform samplerCube e;"
- "uniform float t;"
- "uniform vec3 m,i,a,n;"
- "in vec3 c,v;"
- "out vec4 o;"
- "vec3 r(vec3 d,vec3 l,vec3 s)"
+ "uniform samplerCube v;"
+ "uniform float s;"
+ "uniform vec3 f,n,z,e;"
+ "in vec3 m,d;"
+ "out vec4 r;"
+ "vec3 t(vec3 v,vec3 m,vec3 f)"
  "{"
-   "float C=1.-clamp(dot(l,s),0.,1.);"
-   "return C*C*C*C*C*(1.-d)+d;"
+   "float r=1.-clamp(dot(m,f),0.,1.);"
+   "return r*r*r*r*r*(1.-v)+v;"
  "}"
  "void main()"
  "{"
-   "vec3 f=i,z=a+mix(f*m,m,.5);"
-   "o=vec4(z,1);"
+   "vec3 v=n,p=z+mix(v*f,f,.5);"
+   "r=vec4(p,1);"
  "}"
- "vec3 r(vec3 l,vec3 y,vec3 u,vec3 f,vec3 d,float w)"
+ "vec3 t(vec3 v,vec3 m,vec3 f,vec3 n,vec3 d,float r)"
  "{"
-   "vec3 s=normalize(l+y),b,Z,Y;"
-   "float X=1.+2048.*(1.-w)*(1.-w);"
-   "b=f;"
-   "Z=vec3(pow(clamp(dot(s,u),0.,1.),X)*(X+4.)/8.);"
-   "Y=r(d,l,s);"
-   "return mix(b,Z,Y);"
+   "vec3 z=normalize(v+m),p,e,c;"
+   "float s=1.+2048.*(1.-r)*(1.-r);"
+   "p=n;"
+   "e=vec3(pow(clamp(dot(z,f),0.,1.),s)*(s+4.)/8.);"
+   "c=t(d,v,z);"
+   "return mix(p,e,c);"
  "}",