add script to scrape glyph usage in drawText calls

git-svn-id: http://skia.googlecode.com/svn/trunk@9353 2bbb7eff-a529-9590-31e7-b0007b416f81

1 files changed, 113 insertions, 0 deletions

diff --git a/tools/lua/glyph-usage.lua b/tools/lua/glyph-usage.lua
new file mode 100644
index 0000000000..2b0c0e12a0
--- /dev/null
+++ b/tools/lua/glyph-usage.lua
@@ -0,0 +1,113 @@
+function tostr(t)
+    local str = ""
+    for k, v in next, t do
+        if #str > 0 then
+            str = str .. ", "
+        end
+        if type(k) == "number" then
+            str = str .. "[" .. k .. "] = "
+        else
+            str = str .. tostring(k) .. " = "
+        end
+        if type(v) == "table" then
+            str = str .. "{ " .. tostr(v) .. " }"
+        else
+            str = str .. tostring(v)
+        end
+    end
+    return str
+end
+
+local canvas        -- holds the current canvas (from startcanvas())
+
+--[[
+    startcanvas() is called at the start of each picture file, passing the
+    canvas that we will be drawing into, and the name of the file.
+    
+    Following this call, there will be some number of calls to accumulate(t)
+    where t is a table of parameters that were passed to that draw-op.
+    
+        t.verb is a string holding the name of the draw-op (e.g. "drawRect")
+    
+    when a given picture is done, we call endcanvas(canvas, fileName)
+]]
+function sk_scrape_startcanvas(c, fileName)
+    canvas = c
+end
+
+--[[
+    Called when the current canvas is done drawing.
+]]
+function sk_scrape_endcanvas(c, fileName)
+    canvas = nil
+end
+
+--[[
+    Called with the parameters to each canvas.draw call, where canvas is the
+    current canvas as set by startcanvas()
+]]
+
+function round(x, mul)
+    mul = mul or 1
+    return math.floor(x * mul + 0.5) / mul
+end
+
+local strikes = {}  -- [fontID_pointsize] = [] unique glyphs
+
+function make_strike_key(paint)
+    return paint:getFontID() * 1000 + paint:getTextSize()
+end
+
+-- array is an array of bools (true), using glyphID as the index
+-- other is just an array[1...N] of numbers (glyphIDs)
+function array_union(array, other)
+    for k, v in next, other do
+        array[v] = true;
+    end
+end
+
+function array_count(array)
+    local n = 0
+    for k in next, array do
+        n = n + 1
+    end
+    return n
+end
+
+function sk_scrape_accumulate(t)
+    verb = t.verb;
+    if verb == "drawPosText" or verb == "drawPosTextH" then
+        if t.glyphs then
+            local key = make_strike_key(t.paint)
+            strikes[key] = strikes[key] or {}
+            array_union(strikes[key], t.glyphs)
+        end
+    end
+end
+
+--[[
+    lua_pictures will call this function after all of the pictures have been
+    "accumulated".
+]]
+function sk_scrape_summarize()
+    local totalCount = 0
+    local strikeCount = 0
+    local min, max = 0, 0
+
+    for k, v in next, strikes do
+        local fontID = round(k / 1000)
+        local size = k - fontID * 1000
+        local count = array_count(v)
+
+        io.write("fontID = ", fontID, ", size = ", size, ", entries = ", count, "\n");
+        
+        min = math.min(min, count)
+        max = math.max(max, count)
+        totalCount = totalCount + count
+        strikeCount = strikeCount + 1
+    end
+    local ave = round(totalCount / strikeCount)
+
+    io.write("\n", "unique glyphs: min = ", min, ", max = ", max, ", ave = ", ave, "\n");
+end
+