From 9265fc3463a0c54a85f48076a73cae57a860ed12 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marcel=20Fabian=20Kr=C3=BCger?= <zauguin@gmail.com>
Date: Fri, 5 Jun 2020 00:26:41 +0200
Subject: [PATCH] Actually working variant of previous commit

You know, there are some days where you are reflecting on why you even
write this stuff. This is one of these days and today I realized that a
theoretical long term goal might be that this becomes actually usable.
Based on that I decided that committing actually correct code might be a
pretty good idea.
---
 luametalatex-back-pdf.lua | 24 +++++++++++++-----------
 1 file changed, 13 insertions(+), 11 deletions(-)

diff --git a/luametalatex-back-pdf.lua b/luametalatex-back-pdf.lua
index 2cf54d1..625d651 100644
--- a/luametalatex-back-pdf.lua
+++ b/luametalatex-back-pdf.lua
@@ -119,17 +119,19 @@ local function projected(m, x, y, w)
   return x*m[1] + y*m[3] + w*m[5], x*m[2] + y*m[4] + w*m[6]
 end
 local do_setmatrix do
-  local numberpattern = (lpeg.R'09'^0 * ('.' * lpeg.R'09'^0)^-1)/tonumber
+  local numberpattern = (lpeg.P'-'^-1 * lpeg.R'09'^0 * ('.' * lpeg.R'09'^0)^-1)/tonumber
   local matrixpattern = numberpattern * ' ' * numberpattern * ' ' * numberpattern * ' ' * numberpattern
-  function whatsithandler.pdf_setmatrix(p, n, x, y, outer)
-    write_matrix(p, a, b, c, d, e, f)
-  end
-  local function do_setmatrix(prop, p, n, x, y, outer)
+  function do_setmatrix(prop, p, n, x, y, outer)
     local m = p.matrix
     local a, b, c, d = matrixpattern:match(prop.data)
+    if not a then
+      print(prop.data)
+      error[[No valid matrix found]]
+    end
     local e, f = (1-a)*x-c*y, (1-d)*y-b*x -- Emulate that the origin is at x, y for this transformation
                                           -- (We could also first translate by (-x, -y), then apply the matrix
                                           --  and translate back, but this is more direct)
+    pdf.write_matrix(a, b, c, d, e, f, p)
     a, b = projected(m, a, b, 0)
     c, d = projected(m, c, d, 0)
     e, f = projected(m, e, f, 1)
@@ -278,10 +280,10 @@ token.luacmd("pdfextension", function(_, imm)
         data = literal,
       })
     node.write(whatsit)
-  elseif token.scan_keyword"push" then
-    local whatsit = node.new(whatsit_id, whatsits.pdf_push)
+  elseif token.scan_keyword"save" then
+    local whatsit = node.new(whatsit_id, whatsits.pdf_save)
     node.setproperty(whatsit, {
-        handle = do_push,
+        handle = do_save,
       })
     node.write(whatsit)
   elseif token.scan_keyword"setmatrix" then
@@ -292,10 +294,10 @@ token.luacmd("pdfextension", function(_, imm)
         data = matrix,
       })
     node.write(whatsit)
-  elseif token.scan_keyword"pop" then
-    local whatsit = node.new(whatsit_id, whatsits.pdf_pop)
+  elseif token.scan_keyword"restore" then
+    local whatsit = node.new(whatsit_id, whatsits.pdf_restore)
     node.setproperty(whatsit, {
-        handle = do_pop,
+        handle = do_restore,
       })
     node.write(whatsit)
   elseif token.scan_keyword"info" then