diff options
Diffstat (limited to 'source/luametatex/source/tex/texmlist.c')
| -rw-r--r-- | source/luametatex/source/tex/texmlist.c | 187 |
1 files changed, 151 insertions, 36 deletions
diff --git a/source/luametatex/source/tex/texmlist.c b/source/luametatex/source/tex/texmlist.c index d91ee50ae..13085dca1 100644 --- a/source/luametatex/source/tex/texmlist.c +++ b/source/luametatex/source/tex/texmlist.c @@ -2,6 +2,52 @@ See license.txt in the root of this project. */ + +/*tex + + Before we get to the code is is good to notice that what we have here is an extension of the + math rendering as implemented in \TEX. There are several reason for additions and changes. One + is that we need to support \OPENTYPE\ fonts and after more than a decade struggling with the + fact that many fonts are a mix between what the \OPENTYPE\ specification describes (its + accuracy evolved a bit over time) and what traditional \TEX\ fonts do. Think of the role that + italic correction plays in \TEX\ and kerns in \OPENTYPE\ math. + + In \LUATEX\ this has resulted in a way to control various elements of the engine so that one + can adapt to the font. Here even more properties can be controlled. However, in the end we + decided that fonts are too inconsistent and unlikely to be fixed, so in \CONTEXT\ we settled + on a combination of engine control and patching fonts runtime (aka goodie tweaks). This does + actually mean that in principle we can remove most of the code related to italic correction + and simplify kerning, which makes for cleaner code. We can then also ditch many control + options. It could also make some of the resulting constructs les scomplex (this is something + that might happen eventually anyway). + + In addition to this, the machinery below also has opened up atoms, fractions, accents, fences, + radicals and more beyond what \LUATEX\ already added. We have more classes (including user + ones), more spacing and penalty control, positioning features, etc. Most of that is not + described here but in documents that come with \CONTEXT\ and articles in user group journals. + + It is unlikely that users will set up the engine beyond what a macro package provides, which + should be reasonable defaults. Keep in mind that the math machinery has never be part of + discussing extensions to \TEX\ and that the math subengine was never touched. So, while + \CONTEXT\ users sort of expect this upgrade path, this is not true for other macro packages, + especially when they are considered standard and provide standard behaviour. This means that + we can go a bit further in setting up the engine (by options and parametsrs) in ways that + provide better output. This means that even with the same input, the output that \CONTEXT\ + produces will look different and hopefully somewhat better. + + One can of course wonder why we think the rendering can be improved and part of the answer is + in the fact that we have double linked node lists. This means that we can go back and forward + over the result. Another apects is that we have less constraints in memory and processor + capabilities, so we can carry around more information and spend more time on analysing and + calculations. Nodes are way bigger and the font system is more dynamic, which comes at a + price not possible when original \TEX\ showed up. One can therefore only admire even more + what Don Knuth came up with, which still performs very well, and what is the robust core of + what we see below! + + HH & MS + +*/ + /*tex The code here has to deal with traditional \TEX\ fonts as well as the more modern \OPENTYPE\ @@ -474,7 +520,7 @@ halfword tex_math_font_char_dp(halfword fnt, halfword chr, halfword style) } inline static halfword tex_aux_new_math_glyph(halfword fnt, halfword chr, quarterword subtype) { - halfword scale = 1000; + halfword scale = scaling_factor; halfword glyph = tex_new_glyph_node(subtype, fnt, tex_get_math_char(fnt, chr, lmt_math_state.size, &scale, math_direction_par), null); /* todo: data */; set_glyph_options(glyph, glyph_options_par); glyph_scale(glyph) = tex_aux_math_glyph_scale(scale); @@ -1511,7 +1557,7 @@ static halfword tex_aux_make_delimiter(halfword target, halfword delimiter, int } } goto FOUND; - } else if (count > 1000) { + } else if (count > scaling_factor) { tex_formatted_warning("fonts", "endless loop in extensible character %U of font %F", curchr, curfnt); goto FOUND; } else if (tex_char_has_tag_from_font(curfnt, curchr, list_tag)) { @@ -2964,7 +3010,7 @@ static void tex_aux_do_make_math_accent(halfword target, halfword accentfnt, hal scaled overshoot = 0; extinfo *extended = NULL; halfword attrlist = node_attr(target); - scaled fraction = accent_fraction(target) > 0 ? accent_fraction(target) : 1000; + scaled fraction = accent_fraction(target) > 0 ? accent_fraction(target) : scaling_factor; scaled skew = 0; scaled offset = 0; scaled innery = 0; @@ -3047,7 +3093,7 @@ static void tex_aux_do_make_math_accent(halfword target, halfword accentfnt, hal } } if (fraction > 0) { - target = tex_xn_over_d(target, fraction, 1000); + target = tex_xn_over_d(target, fraction, scaling_factor); } while (1) { if (tex_char_has_tag_from_font(accentfnt, accentchr, extensible_tag)) { @@ -3448,8 +3494,8 @@ static void tex_aux_calculate_fraction_shifts(halfword target, int style, int si (void) size; *shift_up = tex_get_math_y_parameter_checked(style, up); *shift_down = tex_get_math_y_parameter_checked(style, down); - *shift_up = tex_round_xn_over_d(*shift_up, fraction_v_factor(target), 1000); - *shift_down = tex_round_xn_over_d(*shift_down, fraction_v_factor(target), 1000); + *shift_up = tex_round_xn_over_d(*shift_up, fraction_v_factor(target), scaling_factor); + *shift_down = tex_round_xn_over_d(*shift_down, fraction_v_factor(target), scaling_factor); } static void tex_aux_calculate_fraction_shifts_stack(halfword target, int style, int size, halfword numerator, halfword denominator, scaled *shift_up, scaled *shift_down, scaled *delta) @@ -3584,7 +3630,7 @@ static halfword tex_aux_make_skewed_fraction(halfword target, int style, int siz delimiterextremes extremes = { .tfont = null_font, .tchar = 0, .bfont = null_font, .bchar = 0, .height = 0, .depth = 0 }; scaled tolerance = tex_get_math_y_parameter_default(style, math_parameter_skewed_delimiter_tolerance, 0); scaled shift_up = tex_get_math_y_parameter_checked(style, math_parameter_skewed_fraction_vgap); - scaled shift_down = tex_round_xn_over_d(shift_up, fraction_v_factor(target), 1000); + scaled shift_down = tex_round_xn_over_d(shift_up, fraction_v_factor(target), scaling_factor); (void) kerns; shift_up = shift_down; /*tex The |shift_up| value might change later. */ tex_aux_wrap_fraction_parts(target, style, size, &numerator, &denominator, 0); @@ -3598,7 +3644,7 @@ static halfword tex_aux_make_skewed_fraction(halfword target, int style, int siz Construct a hlist box for the fraction, according to |hgap| and |vgap|. */ hgap = tex_get_math_x_parameter_checked(style, math_parameter_skewed_fraction_hgap); - hgap = tex_round_xn_over_d(hgap, fraction_h_factor(target), 1000); + hgap = tex_round_xn_over_d(hgap, fraction_h_factor(target), scaling_factor); { scaled ht = box_height(numerator) + shift_up; scaled dp = box_depth(numerator) - shift_up; @@ -3828,8 +3874,8 @@ static void tex_aux_get_shifts(int mode, int style, scaled delta, scaled *top, s break; case 1: /*tex |MathConstants| driven */ - *top = tex_round_xn_over_d(delta, tex_get_math_parameter_default(style, math_parameter_nolimit_sup_factor, 0), 1000); - *bot = -tex_round_xn_over_d(delta, tex_get_math_parameter_default(style, math_parameter_nolimit_sub_factor, 0), 1000); + *top = tex_round_xn_over_d(delta, tex_get_math_parameter_default(style, math_parameter_nolimit_sup_factor, 0), scaling_factor); + *bot = -tex_round_xn_over_d(delta, tex_get_math_parameter_default(style, math_parameter_nolimit_sub_factor, 0), scaling_factor); break ; case 2: /*tex no correction */ @@ -3849,7 +3895,7 @@ static void tex_aux_get_shifts(int mode, int style, scaled delta, scaled *top, s default : /*tex above 15: for quickly testing values */ *top = 0; - *bot = (mode > 15) ? -tex_round_xn_over_d(delta, mode, 1000) : 0; + *bot = (mode > 15) ? -tex_round_xn_over_d(delta, mode, scaling_factor) : 0; break; } } @@ -6831,6 +6877,11 @@ static void tex_mlist_to_hlist_size_fences(mliststate *state) } } +/*tex + The mathboundary feature, where 0/2 push, 1/3 pop, 2/3 take an penalty delta, is only there for + special testing by MS and me, so don't depend on that for now. +*/ + static void tex_mlist_to_hlist_finalize_list(mliststate *state) { halfword recent = null; /*tex Watch out: can be wiped, so more a signal! */ @@ -6848,6 +6899,10 @@ static void tex_mlist_to_hlist_finalize_list(mliststate *state) halfword current = state->mlist; halfword p = temp_head; halfword ghost = null; + int boundarylevel = 0; + int boundaryfactor = scaling_factor; + int nestinglevel = 0; + int nestingfactor = scaling_factor; node_next(p) = null; tex_aux_set_current_math_size(current_style); tex_aux_set_current_math_scale(state->scale); @@ -7019,10 +7074,38 @@ static void tex_mlist_to_hlist_finalize_list(mliststate *state) default: break; } + case boundary_node: + if (node_subtype(current) == math_boundary) { + halfword l = boundary_data(current); + switch(l) { + case 0: + case 2: + boundarylevel++; + if (l == 2) { + boundaryfactor = boundary_reserved(current) ? boundary_reserved(current) : scaling_factor; + } + break; + case 1: + case 3: + if (boundarylevel > 0) { + boundarylevel--; + if (l == 2) { + boundaryfactor = boundary_reserved(current) ? boundary_reserved(current) : scaling_factor; + } + } else { + tex_formatted_warning("math", "invalid math boundary %i nesting", l); + } + break; + default: + tex_formatted_warning("math", "invalid math boundary value"); + /* error */ + break; + } + } + goto PICKUP; // case glyph_node: case disc_node: case hlist_node: - case boundary_node: case whatsit_node: case penalty_node: case rule_node: @@ -7031,6 +7114,7 @@ static void tex_mlist_to_hlist_finalize_list(mliststate *state) case mark_node: case par_node: case kern_node: + PICKUP: tex_couple_nodes(p, current); p = current; current = node_next(current); @@ -7201,16 +7285,40 @@ static void tex_mlist_to_hlist_finalize_list(mliststate *state) /*tex Do we still want this check in infinite. */ - if (state->penalties && pre_penalty < infinite_penalty && node_type(last) != penalty_node) { - /*tex no checking of prev node type */ - halfword penalty = tex_new_penalty_node(pre_penalty, math_pre_penalty_subtype); - tex_attach_attribute_list_copy(penalty, current); - tex_couple_nodes(p, penalty); - p = penalty; - if (tracing_math_par >= 2) { - tex_begin_diagnostic(); - tex_print_format("[math: pre penalty, left %n, right %n, amount %i]", recent_subtype, current_subtype, penalty_amount(penalty)); - tex_end_diagnostic(); + if (tex_math_has_class_option(current_subtype, push_nesting_class_option)) { + nestinglevel++; + switch (current_style) { + case display_style: + case cramped_display_style: + nestingfactor = math_display_penalty_factor_par ? math_display_penalty_factor_par : scaling_factor; + break; + default: + nestingfactor = math_inline_penalty_factor_par ? math_inline_penalty_factor_par : scaling_factor; + break; + } + } else if (tex_math_has_class_option(current_subtype, pop_nesting_class_option) && nestinglevel > 0) { + nestinglevel--; + if (nestinglevel == 0) { + nestingfactor = scaling_factor; + } + } + if (state->penalties && node_type(last) != penalty_node && pre_penalty <= infinite_penalty && (! boundarylevel || (boundaryfactor != scaling_factor || nestingfactor != scaling_factor))) { + if (boundaryfactor != scaling_factor) { + pre_penalty = tex_xn_over_d(pre_penalty, boundaryfactor, scaling_factor); + } else if (nestingfactor != scaling_factor && tex_math_has_class_option(current_subtype, obey_nesting_class_option)) { + pre_penalty = tex_xn_over_d(pre_penalty, nestingfactor, scaling_factor); + } + if (pre_penalty < infinite_penalty) { + /*tex no checking of prev node type */ + halfword penalty = tex_new_penalty_node(pre_penalty, math_pre_penalty_subtype); + tex_attach_attribute_list_copy(penalty, current); + tex_couple_nodes(p, penalty); + p = penalty; + if (tracing_math_par >= 2) { + tex_begin_diagnostic(); + tex_print_format("[math: pre penalty, left %n, right %n, amount %i]", recent_subtype, current_subtype, penalty_amount(penalty)); + tex_end_diagnostic(); + } } } if (tex_math_has_class_option(current_subtype, remove_italic_correction_class_option)) { @@ -7298,20 +7406,27 @@ static void tex_mlist_to_hlist_finalize_list(mliststate *state) We can actually drop the omit check because we pair by class. */ - if (state->penalties && node_next(current) && post_penalty < infinite_penalty) { - halfword recent = node_next(current); - recent_type = node_type(recent); - recent_subtype = node_subtype(recent); - /* todo: maybe also check the mainclass of the recent */ - if ((recent_type != penalty_node) && ! (recent_type == simple_noad && tex_math_has_class_option(recent_subtype, omit_penalty_class_option))) { - halfword penalty = tex_new_penalty_node(post_penalty, math_post_penalty_subtype); - tex_attach_attribute_list_copy(penalty, current); - tex_couple_nodes(p, penalty); - p = penalty; - if (tracing_math_par >= 2) { - tex_begin_diagnostic(); - tex_print_format("[math: post penalty, left %n, right %n, amount %i]", recent_subtype, current_subtype, penalty_amount(penalty)); - tex_end_diagnostic(); + if (state->penalties && node_next(current) && post_penalty <= infinite_penalty && (! boundarylevel || (boundaryfactor != scaling_factor || nestingfactor != scaling_factor))) { + if (boundaryfactor != scaling_factor) { + post_penalty = tex_xn_over_d(post_penalty, boundaryfactor, scaling_factor); + } else if (nestingfactor != scaling_factor && tex_math_has_class_option(current_subtype, obey_nesting_class_option)) { + post_penalty = tex_xn_over_d(post_penalty, nestingfactor, scaling_factor); + } + if (post_penalty < infinite_penalty) { + halfword recent = node_next(current); + recent_type = node_type(recent); + recent_subtype = node_subtype(recent); + /* todo: maybe also check the mainclass of the recent */ + if ((recent_type != penalty_node) && ! (recent_type == simple_noad && tex_math_has_class_option(recent_subtype, omit_penalty_class_option))) { + halfword penalty = tex_new_penalty_node(post_penalty, math_post_penalty_subtype); + tex_attach_attribute_list_copy(penalty, current); + tex_couple_nodes(p, penalty); + p = penalty; + if (tracing_math_par >= 2) { + tex_begin_diagnostic(); + tex_print_format("[math: post penalty, left %n, right %n, amount %i]", recent_subtype, current_subtype, penalty_amount(penalty)); + tex_end_diagnostic(); + } } } } |