Fixing the --pt Font Size Bug | Generated by AI

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How the --pt font size bug was fixed in ww pdf markdown-pdf

The Problem

The --pt flag existed in the CLI but had zero effect on actual PDF output. Body text was always 12pt regardless of what --pt value was passed.

Root Causes (there were multiple, layered)

Bug 1: LaTeX article class ignores non-standard classoptions

The original code passed --pt 48 as -V classoption=48pt, which becomes \documentclass[48pt]{article}. But LaTeX’s article class only supports 10pt, 11pt, 12pt — any other value is silently ignored with a warning. So --pt 48 did nothing.

Fix: Use \renewcommand{\normalsize}{\fontsize{48}{60}\selectfont} instead of classoption.

Bug 2: -V header-includes= collapses newlines

When we moved to -V header-includes=\renewcommand{...}\n\usepackage{titlesec}\n..., pandoc’s -V flag treated the entire value as a single string, collapsing \n into literal characters. Multiple LaTeX commands on one line = syntax error or ignored.

Fix: Write the header-includes content to a temp .tex file and use --include-in-header <file> instead. Pandoc reads the file verbatim, preserving all newlines. Temp file is cleaned up after pandoc exits.

Bug 3: titlesec package needed for heading control

Even once \normalsize was correctly set to 48pt, LaTeX’s \section command uses its own hardcoded size formula (e.g., \Large, \large) that doesn’t reference \normalsize. So headings stayed at the class default while body text grew.

Fix: Add \usepackage{titlesec} and explicit \titleformat commands:

\titleformat{\section}{\bfseries\fontsize{62}{74}\selectfont}{}{}{}
\titleformat{\subsection}{\bfseries\fontsize{55}{66}\selectfont}{}{}{}
\titleformat{\subsubsection}{\bfseries\normalsize}{}{}{}

Bug 4 (the final, hardest one): setspace package’s \setstretch overrides \normalsize

This was the most insidious bug. The original code used -V linestretch=1.5 to set line spacing. Pandoc’s template generates:

% In preamble:
\usepackage{setspace}

% After \begin{document}:
\setstretch{1.5}

The setspace package’s \setstretch command internally redefines \normalsize back to the class default (12pt) with the new stretch factor. So the execution order was:

  1. \documentclass[12pt]{article} → \normalsize = 12pt
  2. \usepackage{setspace} → loads package
  3. Our \renewcommand{\normalsize}{\fontsize{48}{60}\selectfont} → \normalsize = 48pt ✓
  4. \AtBeginDocument{\normalsize} → applies 48pt at doc start ✓
  5. \setstretch{1.5} (after \begin{document}) → REDEFINES \normalsize back to 12pt ✗

Step 5 silently undid everything. We confirmed this by compiling a minimal .tex file without setspace — body text was correctly 48pt. Adding setspace back broke it.

Fix: Include \usepackage{setspace} and \setstretch{1.5} in our own --include-in-header file, BEFORE our \renewcommand{\normalsize}. Remove -V linestretch=1.5 from the pandoc command. This way:

  1. \usepackage{setspace} → loads package
  2. \setstretch{1.5} → sets stretch, redefines \normalsize to 12pt+stretch
  3. \renewcommand{\normalsize}{\fontsize{48}{60}\selectfont} → overrides back to 48pt
  4. \AtBeginDocument{\normalsize} → applies 48pt at doc start
  5. No more \setstretch after \begin{document} → 48pt persists ✓

Verification

Files changed

~/projects/ww/ww/pdf/pdf_base.py — the text_to_pdf_from_markdown() function. Key changes:

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