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- NEW: added environment-modifying commands for font sizes: \c \\tiny ... \c \\normalsize ... \c \\Huge
- NEW: added environment-modifying commands for text color: \c {\\color{COL}...}
- NEW: added environment-modifying commands for text formatting: \c {\\bfseries...}, \c {\\itshape...}, \c {\\bf...}, \c {\\it...}, \c {\\sffamily...}, \c {\\ttfamily...}, ...
- REFACTORING: split up several .h/.cpp-files in nodes subdirectory
70 lines
2.7 KiB
Plaintext
70 lines
2.7 KiB
Plaintext
/*!
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\defgroup jkqtmathtext_renderingmodel JKQTMathText Rendering Model
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\ingroup jkqtmathtext_general
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\section jkqtmathtext_renderingmodel_basics Basics
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JKQTMathText parses an input string of mathematical markup (i.e. LaTeX) and in a first step generates a memory representation of the it (cf. \ref jkqtmathtext_items ).
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Then this memory representation is used to draw the represented math using the renndering API of <a href="https://doc.qt.io/qt-6/qpainter.html">QPainter</a>.
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As an example, we look at the following LaTeX markup, representing the solution to a quadratic equation:
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\code{.tex}
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$x_{1/2} = \frac{-b\pm\sqrt{b^2-4ac}}{2a}$
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\endcode
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LaTeX itself would render this as follows:
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\image html jkqtmathtext/jkqtmathtext_doc_quadraticeq_latex.png
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JKQTMathText produces this output:
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\image html jkqtmathtext/jkqtmathtext_doc_quadraticeq.png
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The memory representation of the expression above looks like this:
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\image html jkqtmathtext/jkqtmathtext_doc_quadraticeq_tree.png
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\note The memory representation is independent of the actual math markup language (e.g. LaTeX) which was initially parsed.
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But of course it is modelled, so the features of the supported markup languages are supported by the memory model.
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\note Also the parser performs optimizations on the tree, e.g. by removing a JKQTMathTextHorizontalListNode if it contains
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only one entry!
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You can see that each node corresponds to a box, if these are overlayed over the rendering:
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\image html jkqtmathtext/jkqtmathtext_doc_quadraticeq_boxes.png
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The box, representing each node, is characterized by its width and height, as well as the ascent (or "baseline-height"):
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\image html jkqtmathtext_node_geo.png
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\section jkqtmathtext_renderingmodel_linebreaks Linebreaks and Blocks
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As described above, JKQTMathText represents the mathematicl markup as a tree of boxes. When calling JKQTMathText::parse() without
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any additional parameters, the base-node is a JKQTMathTextVerticalListNode that can represent several lines of text. A new line
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is started when a \c \\\\ or \c \\newline command is found. Automatic line breaking is not performed, i.e. each line can possibly
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become very long, also longer than the available space for drawing! Also lineabreaks are only allowed directly in the current
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context. You cannot write
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\code.tex
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\textbf{line1\\text2}
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\endcode
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but have to write
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\code.tex
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\textbf{line1}\\
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\textbf{line2}
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\endcode
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With environment-altering instructions like \c \\bfserie or \c \\it this can be overcome: If you write
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\code.tex
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\bf line1\\
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line2
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\endcode
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both lines are typeset in bold face!
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*/
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