layout: remove line-height

This was a bad idea that, despite my best efforts, never worked
properly.

6 files changed, 20 insertions, 77 deletions

diff --git a/src/css/cssvalues.nim b/src/css/cssvalues.nim
index 3faf13e5..6eac8148 100644
--- a/src/css/cssvalues.nim
+++ b/src/css/cssvalues.nim
@@ -67,7 +67,6 @@ type
     cptPaddingRight = "padding-right"
     cptPaddingBottom = "padding-bottom"
     cptVerticalAlign = "vertical-align"
-    cptLineHeight = "line-height"
     cptTextAlign = "text-align"
     cptListStylePosition = "list-style-position"
     cptBackgroundColor = "background-color"
@@ -426,7 +425,6 @@ const ValueTypes = [
   cptPaddingRight: cvtLength,
   cptPaddingBottom: cvtLength,
   cptVerticalAlign: cvtVerticalAlign,
-  cptLineHeight: cvtLength,
   cptTextAlign: cvtTextAlign,
   cptListStylePosition: cvtListStylePosition,
   cptBackgroundColor: cvtColor,
@@ -463,9 +461,9 @@ const ValueTypes = [
 
 const InheritedProperties = {
   cptColor, cptFontStyle, cptWhiteSpace, cptFontWeight, cptTextDecoration,
-  cptWordBreak, cptListStyleType, cptLineHeight, cptTextAlign,
-  cptListStylePosition, cptCaptionSide, cptBorderSpacing, cptBorderCollapse,
-  cptQuotes, cptVisibility, cptTextTransform
+  cptWordBreak, cptListStyleType, cptTextAlign, cptListStylePosition,
+  cptCaptionSide, cptBorderSpacing, cptBorderCollapse, cptQuotes,
+  cptVisibility, cptTextTransform
 }
 
 func shorthandType(s: string): CSSShorthandType =
@@ -1068,19 +1066,6 @@ func cssVerticalAlign(cval: CSSComponentValue): Opt[CSSVerticalAlign] =
       ))
   return err()
 
-func cssLineHeight(cval: CSSComponentValue): Opt[CSSLength] =
-  if cval of CSSToken:
-    let tok = CSSToken(cval)
-    case tok.tokenType
-    of cttNumber:
-      return cssLength(tok.nvalue * 100, "%")
-    of cttIdent:
-      if tok.value.equalsIgnoreCase("normal"):
-        return ok(CSSLengthAuto)
-    else:
-      return cssLength(tok, has_auto = false)
-  return err()
-
 func cssCounterReset(cvals: openArray[CSSComponentValue]):
     Opt[seq[CSSCounterReset]] =
   template die =
@@ -1183,8 +1168,6 @@ proc parseValue(cvals: openArray[CSSComponentValue]; t: CSSPropertyType):
   of cvtColor: return_new color, ?cssColor(cval)
   of cvtLength:
     case t
-    of cptLineHeight:
-      return_new length, ?cssLineHeight(cval)
     of cptMaxWidth, cptMaxHeight, cptMinWidth, cptMinHeight:
       return_new length, ?cssMaxMinSize(cval)
     of cptPaddingLeft, cptPaddingRight, cptPaddingTop, cptPaddingBottom:
@@ -1243,8 +1226,8 @@ func getInitialColor(t: CSSPropertyType): CellColor =
 
 func getInitialLength(t: CSSPropertyType): CSSLength =
   case t
-  of cptWidth, cptHeight, cptLineHeight, cptLeft, cptRight, cptTop, cptBottom,
-      cptMaxWidth, cptMaxHeight, cptMinWidth, cptMinHeight, cptFlexBasis:
+  of cptWidth, cptHeight, cptLeft, cptRight, cptTop, cptBottom, cptMaxWidth,
+      cptMaxHeight, cptMinWidth, cptMinHeight, cptFlexBasis:
     return CSSLengthAuto
   else:
     return CSSLength(auto: false, unit: cuPx, num: 0)
diff --git a/src/layout/engine.nim b/src/layout/engine.nim
index 8ba12729..50cf5cfb 100644
--- a/src/layout/engine.nim
+++ b/src/layout/engine.nim
@@ -213,7 +213,6 @@ type
   LineBoxState = object
     atomStates: seq[InlineAtomState]
     baseline: LayoutUnit
-    lineHeight: LayoutUnit
     paddingTop: LayoutUnit
     paddingBottom: LayoutUnit
     hasExclusion: bool
@@ -259,8 +258,6 @@ type
     fragment: InlineFragment
     firstLine: bool
     startOffsetTop: Offset
-    # computed line-height of fragment
-    lineHeight: LayoutUnit
     # we do not want to collapse newlines over tag boundaries, so these are
     # in state
     lastrw: int # last rune width of the previous word
@@ -280,9 +277,6 @@ func cellWidth(lctx: LayoutContext): int =
 func cellWidth(ictx: InlineContext): int =
   ictx.lctx.cellWidth
 
-func cellHeight(lctx: LayoutContext): int =
-  lctx.attrs.ppl
-
 func cellHeight(ictx: InlineContext): int =
   ictx.lctx.attrs.ppl
 
@@ -313,16 +307,10 @@ func computeShift(ictx: InlineContext; state: InlineState): LayoutUnit =
 proc applyLineHeight(ictx: InlineContext; state: var LineBoxState;
     computed: CSSComputedValues) =
   let lctx = ictx.lctx
-  let lineHeight = if computed{"line-height"}.auto: # ergo normal
-    lctx.cellHeight.toLayoutUnit()
-  else:
-    # Percentage: refers to the font size of the element itself.
-    computed{"line-height"}.px(lctx, lctx.cellHeight)
   let paddingTop = computed{"padding-top"}.px(lctx, ictx.space.w)
   let paddingBottom = computed{"padding-bottom"}.px(lctx, ictx.space.w)
   state.paddingTop = max(paddingTop, state.paddingTop)
   state.paddingBottom = max(paddingBottom, state.paddingBottom)
-  state.lineHeight = max(lineHeight, state.lineHeight)
 
 proc newWord(ictx: var InlineContext) =
   ictx.word = InlineAtom(
@@ -486,13 +474,11 @@ proc shiftAtoms(ictx: var InlineContext; marginTop: LayoutUnit) =
 
 # Align atoms (inline boxes, text, etc.) on both axes.
 proc alignLine(ictx: var InlineContext) =
-  # Start with line-height as the baseline and line height.
-  let lineHeight = ictx.lbstate.lineHeight
-  ictx.lbstate.size.h = lineHeight
-  let ch = ictx.cellHeight
-  # Baseline is what we computed in addAtom, or lineHeight if that's greater.
-  ictx.lbstate.baseline = max(ictx.lbstate.baseline, lineHeight)
-    .round(ch)
+  # Start with cell height as the baseline and line height.
+  let ch = ictx.cellHeight.toLayoutUnit()
+  ictx.lbstate.size.h = ch
+  # Baseline is what we computed in addAtom, or cell height if that's greater.
+  ictx.lbstate.baseline = max(ictx.lbstate.baseline, ch).round(ictx.cellHeight)
   # Resize according to the baseline and atom sizes.
   ictx.lbstate.size.h = ictx.lbstate.resizeLine(ictx.lctx)
   # Now we can calculate the actual position of atoms inside the line.
@@ -504,14 +490,11 @@ proc alignLine(ictx: var InlineContext) =
   ictx.shiftAtoms(marginTop)
   # Ensure that the line is exactly as high as its highest atom demands,
   # rounded up to the next line.
-  # (This is almost the same as completely ignoring line height. However, there
-  # *is* a difference, because line height is still taken into account when
-  # positioning the atoms.)
-  ictx.lbstate.size.h = ictx.lbstate.minHeight.ceilTo(ch)
-  # Now, if we got a height that is lower than cell height *and* line height,
-  # then set it back to the cell height. (This is to avoid the situation where
-  # we would swallow hard line breaks with <br>.)
-  if lineHeight >= ch and ictx.lbstate.size.h < ch:
+  ictx.lbstate.size.h = ictx.lbstate.minHeight.ceilTo(ictx.cellHeight)
+  # Now, if we got a height that is lower than cell height, then set it
+  # back to the cell height. (This is to avoid the situation where we
+  # would swallow hard line breaks with <br>.)
+  if ictx.lbstate.size.h < ch:
     ictx.lbstate.size.h = ch
   # Set the line height to size.h.
   ictx.lbstate.height = ictx.lbstate.size.h
@@ -659,8 +642,6 @@ proc addAtom(ictx: var InlineContext; state: var InlineState;
     #TODO this is inefficient
     while ictx.shouldWrap2(atom.size.w + shift):
       ictx.applyLineHeight(ictx.lbstate, state.fragment.computed)
-      ictx.lbstate.lineHeight = max(ictx.lbstate.lineHeight,
-        ictx.cellHeight)
       ictx.finishLine(state, wrap = false, force = true)
       # Recompute on newline
       shift = ictx.computeShift(state)
@@ -684,7 +665,7 @@ proc addAtom(ictx: var InlineContext; state: var InlineState;
     ictx.lbstate.size.w += atom.size.w
     let baseline = case iastate.vertalign.keyword
     of VerticalAlignBaseline:
-      let len = iastate.vertalign.length.px(ictx.lctx, state.lineHeight)
+      let len = iastate.vertalign.length.px(ictx.lctx, ictx.cellHeight)
       iastate.baseline + len
     of VerticalAlignTop, VerticalAlignBottom:
       atom.size.h
@@ -1504,13 +1485,6 @@ proc addInlineImage(ictx: var InlineContext; state: var InlineState;
         computed{"min-width"}.unit != cuPerc:
       ictx.root.state.xminwidth = max(ictx.root.state.xminwidth, atom.size.w)
 
-func calcLineHeight(computed: CSSComputedValues; lctx: LayoutContext):
-    LayoutUnit =
-  if computed{"line-height"}.auto: # ergo normal
-    return lctx.cellHeight.toLayoutUnit()
-  # Percentage: refers to the font size of the element itself.
-  return computed{"line-height"}.px(lctx, lctx.cellHeight)
-
 proc layoutInline(ictx: var InlineContext; fragment: InlineFragment) =
   let lctx = ictx.lctx
   let computed = fragment.computed
@@ -1535,8 +1509,7 @@ proc layoutInline(ictx: var InlineContext; fragment: InlineFragment) =
     startOffsetTop: offset(
       x = ictx.lbstate.widthAfterWhitespace,
       y = ictx.lbstate.offsety
-    ),
-    lineHeight: computed.calcLineHeight(lctx)
+    )
   )
   ictx.applyLineHeight(ictx.lbstate, computed)
   case fragment.t
@@ -1576,10 +1549,7 @@ proc layoutRootInline0(bctx: var BlockContext; ictx: var InlineContext;
   ictx.layoutInline(root.fragment)
   if ictx.lastTextFragment != nil:
     let fragment = ictx.lastTextFragment
-    var state = InlineState(
-      fragment: fragment,
-      lineHeight: fragment.computed.calcLineHeight(ictx.lctx)
-    )
+    var state = InlineState(fragment: fragment)
     ictx.finishLine(state, wrap = false)
 
 proc layoutRootInline(bctx: var BlockContext; root: RootInlineFragment;
diff --git a/test/layout/inline_split_sizes.color.expected b/test/layout/inline_split_sizes.color.expected
index 636edd8a..39ddcf28 100644
--- a/test/layout/inline_split_sizes.color.expected
+++ b/test/layout/inline_split_sizes.color.expected
@@ -1,9 +1,5 @@
-
 before t
-
 carthago delenda
-
           est
-
 hello after
 
diff --git a/test/layout/inline_split_sizes.html b/test/layout/inline_split_sizes.html
index df50dca5..935607e5 100644
--- a/test/layout/inline_split_sizes.html
+++ b/test/layout/inline_split_sizes.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-before <span style="background-color: red; line-height: 2em"> t<br>
+before <span style="background-color: red"> t<br>
 <div>carthago delenda</div>
-<span style="padding-left: 5em; line-height: 2em"></span><span>est</span><br>
+<span style="padding-left: 5em"></span><span>est</span><br>
 hello</span> after
diff --git a/test/layout/line-height-change.expected b/test/layout/line-height-change.expected
deleted file mode 100644
index ec17045e..00000000
--- a/test/layout/line-height-change.expected
+++ /dev/null
@@ -1,4 +0,0 @@
-
-
-one
-two
diff --git a/test/layout/line-height-change.html b/test/layout/line-height-change.html
deleted file mode 100644
index 1cae1f85..00000000
--- a/test/layout/line-height-change.html
+++ /dev/null
@@ -1,2 +0,0 @@
-<span style="line-height: 2em"><br>one</span><br>
-two