Import ConTeXt math modules

Modules that provide OpenType and Unicode math related functionality,
not very tested yet, but it seems to magically fix some of unicode-math
issues.

May be it should be trimmed a bit, since a good chunk of the code is of
no use to us.

1 files changed, 313 insertions, 0 deletions

diff --git a/otfl-math-dim.lua b/otfl-math-dim.lua
new file mode 100644
index 0000000..62d8051
--- /dev/null
+++ b/otfl-math-dim.lua
@@ -0,0 +1,313 @@
+if not modules then modules = { } end modules ['math-dim'] = {
+    version   = 1.001,
+    comment   = "companion to math-ini.mkiv",
+    author    = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
+    copyright = "PRAGMA ADE / ConTeXt Development Team",
+    license   = "see context related readme files"
+}
+
+-- Beware: only Taco really understands in depth what these dimensions do so
+-- if you run into problems ...
+
+local abs, next = math.abs, next
+
+mathematics = mathematics or { }
+
+local defaults = {
+    ['axis']={
+        ['default']={ "AxisHeight", "axis_height" },
+    },
+    ['accent_base_height']={
+        ['default']={ "AccentBaseHeight", "x_height" },
+    },
+    ['fraction_del_size']={
+        ['default']={ "FractionDelimiterSize", "delim2" },
+        ['cramped_display_style']={ "FractionDelimiterDisplayStyleSize", "delim1" },
+        ['display_style']={ "FractionDelimiterDisplayStyleSize", "delim1" },
+     },
+    ['fraction_denom_down']={
+        ['default']={ "FractionDenominatorShiftDown", "denom2" },
+        ['cramped_display_style']={ "FractionDenominatorDisplayStyleShiftDown", "denom1" },
+        ['display_style']={ "FractionDenominatorDisplayStyleShiftDown", "denom1" },
+     },
+    ['fraction_denom_vgap']={
+        ['default']={ "FractionDenominatorGapMin", "default_rule_thickness" },
+        ['cramped_display_style']={ "FractionDenominatorDisplayStyleGapMin", "3*default_rule_thickness" },
+        ['display_style']={ "FractionDenominatorDisplayStyleGapMin", "3*default_rule_thickness" },
+     },
+    ['fraction_num_up']={
+        ['default']={ "FractionNumeratorShiftUp", "num2" },
+        ['cramped_display_style']={ "FractionNumeratorDisplayStyleShiftUp", "num1" },
+        ['display_style']={ "FractionNumeratorDisplayStyleShiftUp", "num1" },
+     },
+     ['fraction_num_vgap']={
+        ['default']={ "FractionNumeratorGapMin", "default_rule_thickness" },
+        ['cramped_display_style']={ "FractionNumeratorDisplayStyleGapMin", "3*default_rule_thickness" },
+        ['display_style']={ "FractionNumeratorDisplayStyleGapMin", "3*default_rule_thickness" },
+     },
+    ['fraction_rule']={
+        ['default']={ "FractionRuleThickness", "default_rule_thickness" },
+     },
+    ['limit_above_bgap']={
+        ['default']={ "UpperLimitBaselineRiseMin", "big_op_spacing3" },
+     },
+    ['limit_above_kern']={
+        ['default']={ "0", "big_op_spacing5" },
+     },
+    ['limit_above_vgap']={
+        ['default']={ "UpperLimitGapMin", "big_op_spacing1" },
+     },
+    ['limit_below_bgap']={
+        ['default']={ "LowerLimitBaselineDropMin", "big_op_spacing4" },
+     },
+    ['limit_below_kern']={
+        ['default']={ "0", "big_op_spacing5" },
+     },
+    ['limit_below_vgap']={
+        ['default']={ "LowerLimitGapMin", "big_op_spacing2" },
+     },
+
+--~     ['....']={
+--~         ['default']={ "DisplayOperatorMinHeight", "....." },
+--~     },
+
+    ['overbar_kern']={
+        ['default']={ "OverbarExtraAscender", "default_rule_thickness" },
+     },
+    ['overbar_rule']={
+        ['default']={ "OverbarRuleThickness", "default_rule_thickness" },
+     },
+    ['overbar_vgap']={
+        ['default']={ "OverbarVerticalGap", "3*default_rule_thickness" },
+     },
+    ['quad']={
+        ['default']={ "font_size(f)", "math_quad" },
+     },
+    ['radical_kern']={
+        ['default']={ "RadicalExtraAscender", "default_rule_thickness" },
+     },
+    ['radical_rule']={
+        ['default']={ "RadicalRuleThickness", "<not set>" },
+     },
+    ['radical_vgap']={
+        ['default']={ "RadicalVerticalGap", "default_rule_thickness+(abs(default_rule_thickness)/4)" },
+        ['display_style']={ "RadicalDisplayStyleVerticalGap", "default_rule_thickness+(abs(math_x_height)/4)" },
+     },
+    ['space_after_script']={
+        ['default']={ "SpaceAfterScript", "script_space" },
+     },
+    ['stack_denom_down']={
+        ['default']={ "StackBottomShiftDown", "denom2" },
+        ['cramped_display_style']={ "StackBottomDisplayStyleShiftDown", "denom1" },
+        ['display_style']={ "StackBottomDisplayStyleShiftDown", "denom1" },
+     },
+    ['stack_num_up']={
+        ['default']={ "StackTopShiftUp", "num3" },
+        ['cramped_display_style']={ "StackTopDisplayStyleShiftUp", "num1" },
+        ['display_style']={ "StackTopDisplayStyleShiftUp", "num1" },
+     },
+    ['stack_vgap']={
+        ['default']={ "StackGapMin", "3*default_rule_thickness" },
+        ['cramped_display_style']={ "StackDisplayStyleGapMin", "7*default_rule_thickness" },
+        ['display_style']={ "StackDisplayStyleGapMin", "7*default_rule_thickness" },
+     },
+    ['sub_shift_down']={
+        ['default']={ "SubscriptShiftDown", "sub1" },
+     },
+    ['sub_shift_drop']={
+        ['default']={ "SubscriptBaselineDropMin", "sub_drop" },
+     },
+    ['sub_sup_shift_down']={
+        ['default']={ "SubscriptShiftDown", "sub2" }, -- todo
+     },
+    ['sub_top_max']={
+        ['default']={ "SubscriptTopMax", "abs(math_x_height*4)/5" },
+     },
+    ['subsup_vgap']={
+        ['default']={ "SubSuperscriptGapMin", "4*default_rule_thickness" },
+     },
+    ['sup_bottom_min']={
+        ['default']={ "SuperscriptBottomMin", "abs(math_x_height)/4" },
+     },
+    ['sup_shift_drop']={
+        ['default']={ "SuperscriptBaselineDropMax", "sup_drop" },
+     },
+    ['sup_shift_up']={
+        ['cramped_display_style']={ "SuperscriptShiftUpCramped", "sup3" },
+        ['cramped_script_script_style']={ "SuperscriptShiftUpCramped", "sup3" },
+        ['cramped_script_style']={ "SuperscriptShiftUpCramped", "sup3" },
+        ['cramped_text_style']={ "SuperscriptShiftUpCramped", "sup3" },
+        ['display_style']={ "SuperscriptShiftUp", "sup1" },
+        ['script_script_style']={ "SuperscriptShiftUp", "sup2" },
+        ['script_style']={ "SuperscriptShiftUp", "sup2" },
+        ['text_style']={ "SuperscriptShiftUp", "sup2" },
+     },
+    ['sup_sub_bottom_max']={
+        ['default']={ "SuperscriptBottomMaxWithSubscript", "abs(math_x_height*4)/5" },
+     },
+    ['underbar_kern']={
+        ['default']={ "UnderbarExtraDescender", "0" },
+     },
+    ['underbar_rule']={
+        ['default']={ "UnderbarRuleThickness", "default_rule_thickness" },
+    },
+    ['underbar_vgap']={
+        ['default']={ "UnderbarVerticalGap", "3*default_rule_thickness" },
+    },
+    ['connector_overlap_min']={
+        ['default']={ "MinConnectorOverlap", "0.25*default_rule_thickness" },
+     },
+    ['over_delimiter_vgap']={
+        ['default']={ "StretchStackGapBelowMin", "big_op_spacing1" },
+    },
+    ['over_delimiter_bgap']={
+        ['default']={ "StretchStackTopShiftUp", "big_op_spacing3" },
+    },
+    ['under_delimiter_vgap']={
+        ['default']={ "StretchStackGapAboveMin", "big_op_spacing2" },
+    },
+    ['under_delimiter_bgap']={
+        ['default']={ "StretchStackBottomShiftDown", "big_op_spacing4" },
+    },
+    ['radical_degree_before']={
+        ['default']={ "RadicalKernBeforeDegree", "(5/18)*quad" },
+    },
+    ['radical_degree_after']={
+        ['default']={ "RadicalKernAfterDegree", "(-10/18)*quad" },
+    },
+    ['radical_degree_raise']={
+        ['default']={ "RadicalDegreeBottomRaisePercent", "60" },
+    },
+}
+
+local styles = {
+    'cramped_display_style',
+    'cramped_script_script_style',
+    'cramped_script_style',
+    'cramped_text_style',
+    'display_style',
+    'script_script_style',
+    'script_style',
+    'text_style',
+}
+
+for k, v in next, defaults do
+    for _, s in next, styles do
+        if not v[s] then
+            v[s] = v.default
+        end
+    end
+end
+
+-- we cannot use a metatable because we do a copy (takes a bit more work)
+--
+-- local mt = { }  setmetatable(defaults,mt)
+--
+-- mt.__index = function(t,s)
+--     return t.default or t.text_style or 0
+-- end
+
+function mathematics.dimensions(dimens)
+    if dimens.SpaceAfterScript then
+        dimens.SubscriptShiftDownWithSuperscript = dimens.SubscriptShiftDown * 1.5
+        return { }, table.fastcopy(dimens)
+    elseif dimens.AxisHeight or dimens.axis_height then
+        local t = { }
+        local math_x_height = dimens.x_height or 10*65526
+        local math_quad = dimens.quad or 10*65526
+        local default_rule_thickness = dimens.FractionDenominatorGapMin or dimens.default_rule_thickness or 0.4*65526
+        dimens["0"] = 0
+        dimens["60"] = 60
+        dimens["0.25*default_rule_thickness"] = default_rule_thickness / 4
+        dimens["3*default_rule_thickness"] = 3 * default_rule_thickness
+        dimens["4*default_rule_thickness"] = 4 * default_rule_thickness
+        dimens["7*default_rule_thickness"] = 7 * default_rule_thickness
+        dimens["(5/18)*quad"] = (math_quad * 5) / 18
+        dimens["(-10/18)*quad"] = - (math_quad * 10) / 18
+        dimens["abs(math_x_height*4)/5"] = abs(math_x_height * 4) / 5
+        dimens["default_rule_thickness+(abs(default_rule_thickness)/4)"] = default_rule_thickness+(abs(default_rule_thickness) / 4)
+        dimens["default_rule_thickness+(abs(math_x_height)/4)"] = default_rule_thickness+(abs(math_x_height) / 4)
+        dimens["abs(math_x_height)/4"] = abs(math_x_height) / 4
+        dimens["abs(math_x_height*4)/5"] = abs(math_x_height * 4) / 5
+        dimens["<not set>"] = false
+        dimens["script_space"] = false -- at macro level
+        for variable, styles in next, defaults do
+            local tt = { }
+            for style, default in next, styles do
+                local one, two = default[1], default[2]
+                local value = dimens[one]
+                if value then
+                    tt[style] = value
+                else
+                    value = dimens[two]
+                    if value == false then
+                        tt[style] = nil
+                    else
+                        tt[style] = value or 0
+                    end
+                end
+            end
+            t[variable] = tt
+        end
+--~ logs.report("warning", "version 0.47 is needed for proper delimited math")
+        local d = {
+            AxisHeight                                  = t . axis                  . text_style,
+            AccentBaseHeight                            = t . accent_base_height    . text_style,
+            FractionDenominatorDisplayStyleGapMin       = t . fraction_denom_vgap   . display_style,
+            FractionDenominatorDisplayStyleShiftDown    = t . fraction_denom_down   . display_style,
+            FractionDenominatorGapMin                   = t . fraction_denom_vgap   . text_style,
+            FractionDenominatorShiftDown                = t . fraction_denom_down   . text_style,
+            FractionNumeratorDisplayStyleGapMin         = t . fraction_num_vgap     . display_style,
+            FractionNumeratorDisplayStyleShiftUp        = t . fraction_num_up       . display_style,
+            FractionNumeratorGapMin                     = t . fraction_num_vgap     . text_style,
+            FractionNumeratorShiftUp                    = t . fraction_num_up       . text_style,
+            FractionRuleThickness                       = t . fraction_rule         . text_style,
+            FractionDelimiterSize                       = t . fraction_del_size     . text_style,
+            FractionDelimiterDisplayStyleSize           = t . fraction_del_size     . display_style,
+            LowerLimitBaselineDropMin                   = t . limit_below_bgap      . text_style,
+            LowerLimitGapMin                            = t . limit_below_vgap      . text_style,
+            OverbarExtraAscender                        = t . overbar_kern          . text_style,
+            OverbarRuleThickness                        = t . overbar_rule          . text_style,
+            OverbarVerticalGap                          = t . overbar_vgap          . text_style,
+            RadicalDisplayStyleVerticalGap              = t . radical_vgap          . display_style,
+            RadicalExtraAscender                        = t . radical_kern          . text_style,
+            RadicalRuleThickness                        = t . radical_rule          . text_style,
+            RadicalVerticalGap                          = t . radical_vgap          . text_style,
+            RadicalKernBeforeDegree                     = t . radical_degree_before . display_style,
+            RadicalKernAfterDegree                      = t . radical_degree_after  . display_style,
+            RadicalDegreeBottomRaisePercent             = t . radical_degree_raise  . display_style,
+            SpaceAfterScript                            = t . space_after_script    . text_style,
+            StackBottomDisplayStyleShiftDown            = t . stack_denom_down      . display_style,
+            StackBottomShiftDown                        = t . stack_denom_down      . text_style,
+            StackDisplayStyleGapMin                     = t . stack_vgap            . display_style,
+            StackGapMin                                 = t . stack_vgap            . text_style,
+            StackTopDisplayStyleShiftUp                 = t . stack_num_up          . display_style,
+            StackTopShiftUp                             = t . stack_num_up          . text_style,
+            SubscriptBaselineDropMin                    = t . sub_shift_drop        . text_style,
+            SubscriptShiftDown                          = t . sub_shift_down        . text_style,
+            SubscriptShiftDownWithSuperscript           = t . sub_sup_shift_down    . text_style,
+            SubscriptTopMax                             = t . sub_top_max           . text_style,
+            SubSuperscriptGapMin                        = t . subsup_vgap           . text_style,
+            SuperscriptBaselineDropMax                  = t . sup_shift_drop        . text_style,
+            SuperscriptBottomMaxWithSubscript           = t . sup_sub_bottom_max    . text_style,
+            SuperscriptBottomMin                        = t . sup_bottom_min        . text_style,
+            SuperscriptShiftUp                          = t . sup_shift_up          . text_style,
+            SuperscriptShiftUpCramped                   = t . sup_shift_up          . cramped_text_style,
+            UnderbarExtraDescender                      = t . underbar_kern         . text_style,
+            UnderbarRuleThickness                       = t . underbar_rule         . text_style,
+            UnderbarVerticalGap                         = t . underbar_vgap         . text_style,
+            UpperLimitBaselineRiseMin                   = t . limit_above_bgap      . text_style,
+            UpperLimitGapMin                            = t . limit_above_vgap      . text_style,
+            MinConnectorOverlap                         = t . connector_overlap_min . text_style,
+            StretchStackGapBelowMin                     = t . over_delimiter_vgap   . text_style,
+            StretchStackTopShiftUp                      = t . over_delimiter_bgap   . text_style,
+            StretchStackGapAboveMin                     = t . under_delimiter_vgap  . text_style,
+            StretchStackBottomShiftDown                 = t . under_delimiter_bgap  . text_style,
+        }
+        d.AccentBaseHeight = 0
+        return t, d -- this might change
+    else
+        return { }, { }
+    end
+end
+