Add support for rotated appendices: implement 90° CCW image rotation for portrait pages, enhance table rendering logic, and update diagram handling directives.

2026-05-17 23:41:45 +02:00
parent 427372b82b
commit d6b3854681
9 changed files with 318 additions and 22 deletions
@@ -2,5 +2,7 @@
 <project version="4">
  <component name="VcsDirectoryMappings">
    <mapping directory="$PROJECT_DIR$" vcs="Git" />
+    <mapping directory="$PROJECT_DIR$/realProjektarbeit" vcs="Git" />
+    <mapping directory="$PROJECT_DIR$/realProjektarbeit/Code" vcs="Git" />
  </component>
 </project>
@@ -4,12 +4,16 @@
    <option name="autoReloadType" value="ALL" />
  </component>
  <component name="ChangeListManager">
-    <list default="true" id="c64f46d5-641a-468c-8fc1-94edec1f2deb" name="Changes" comment="Add support for code appendices: enable code blocks with language labels, line-number gutter, and directive-based integration.">
+    <list default="true" id="c64f46d5-641a-468c-8fc1-94edec1f2deb" name="Changes" comment="Refactor table rendering: replace plain text with `InlineSpan` for rich text support, update row preparation, and improve PDF formatting logic.">
      <change afterPath="$PROJECT_DIR$/real_report.md" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/.idea/workspace.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/workspace.xml" afterDir="false" />
      <change beforePath="$PROJECT_DIR$/MarkdownToIHKChemnits" beforeDir="false" afterPath="$PROJECT_DIR$/MarkdownToIHKChemnits" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/go.sum" beforeDir="false" afterPath="$PROJECT_DIR$/go.sum" afterDir="false" />
      <change beforePath="$PROJECT_DIR$/markdown_parser.go" beforeDir="false" afterPath="$PROJECT_DIR$/markdown_parser.go" afterDir="false" />
      <change beforePath="$PROJECT_DIR$/pdf_content.go" beforeDir="false" afterPath="$PROJECT_DIR$/pdf_content.go" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/pdf_pages.go" beforeDir="false" afterPath="$PROJECT_DIR$/pdf_pages.go" afterDir="false" />
      <change beforePath="$PROJECT_DIR$/pdf_renderer.go" beforeDir="false" afterPath="$PROJECT_DIR$/pdf_renderer.go" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/projektarbeit.pdf" beforeDir="false" afterPath="$PROJECT_DIR$/projektarbeit.pdf" afterDir="false" />
    </list>
    <option name="SHOW_DIALOG" value="false" />
    <option name="HIGHLIGHT_CONFLICTS" value="true" />
@@ -17,7 +21,7 @@
    <option name="LAST_RESOLUTION" value="IGNORE" />
  </component>
  <component name="EmbeddingIndexingInfo">
-    <option name="cachedIndexableFilesCount" value="23" />
+    <option name="cachedIndexableFilesCount" value="25" />
    <option name="fileBasedEmbeddingIndicesEnabled" value="true" />
  </component>
  <component name="GOROOT" url="file:///usr/lib/go" />
@@ -101,7 +105,8 @@
    <MESSAGE value="Add support for appendices: landscape diagrams, tables, and images; implement Kroki URL configurability; enhance directive parsing logic." />
    <MESSAGE value="Update MarkdownToIHKChemnitz: modify core functionality for improved PDF rendering" />
    <MESSAGE value="Add support for code appendices: enable code blocks with language labels, line-number gutter, and directive-based integration." />
-    <option name="LAST_COMMIT_MESSAGE" value="Add support for code appendices: enable code blocks with language labels, line-number gutter, and directive-based integration." />
+    <MESSAGE value="Refactor table rendering: replace plain text with `InlineSpan` for rich text support, update row preparation, and improve PDF formatting logic." />
+    <option name="LAST_COMMIT_MESSAGE" value="Refactor table rendering: replace plain text with `InlineSpan` for rich text support, update row preparation, and improve PDF formatting logic." />
  </component>
  <component name="XDebuggerManager">
    <breakpoint-manager>
@@ -1,9 +1,14 @@
+github.com/boombuler/barcode v1.0.1/go.mod h1:paBWMcWSl3LHKBqUq+rly7CNSldXjb2rDl3JlRe0mD8=
 github.com/go-pdf/fpdf v0.9.0 h1:PPvSaUuo1iMi9KkaAn90NuKi+P4gwMedWPHhj8YlJQw=
 github.com/go-pdf/fpdf v0.9.0/go.mod h1:oO8N111TkmKb9D7VvWGLvLJlaZUQVPM+6V42pp3iV4Y=
+github.com/phpdave11/gofpdi v1.0.13/go.mod h1:vBmVV0Do6hSBHC8uKUQ71JGW+ZGQq74llk/7bXwjDoI=
+github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
+github.com/ruudk/golang-pdf417 v0.0.0-20201230142125-a7e3863a1245/go.mod h1:pQAZKsJ8yyVxGRWYNEm9oFB8ieLgKFnamEyDmSA0BRk=
 github.com/yuin/goldmark v1.8.1 h1:id2TeYXe5FpqwLco0Pso4cNM5Z6Okt4g7kDw9QBMhTA=
 github.com/yuin/goldmark v1.8.1/go.mod h1:ip/1k0VRfGynBgxOz0yCqHrbZXhcjxyuS66Brc7iBKg=
 github.com/yuin/goldmark-meta v1.1.0 h1:pWw+JLHGZe8Rk0EGsMVssiNb/AaPMHfSRszZeUeiOUc=
 github.com/yuin/goldmark-meta v1.1.0/go.mod h1:U4spWENafuA7Zyg+Lj5RqK/MF+ovMYtBvXi1lBb2VP0=
+golang.org/x/image v0.12.0/go.mod h1:Lu90jvHG7GfemOIcldsh9A2hS01ocl6oNO7ype5mEnk=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v2 v2.3.0 h1:clyUAQHOM3G0M3f5vQj7LuJrETvjVot3Z5el9nffUtU=
 gopkg.in/yaml.v2 v2.3.0/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
@@ -46,6 +46,7 @@ func ParseMarkdown(mdPath string) (Config, ast.Node, []byte, error) {
 type parserState struct {
 	nextCodeIsAppendix     bool
 	nextAppendixLandscape  bool // set by @AnhangUMLQuer: — landscape for diagram appendix
+	nextAppendixRotated    bool // set by @AnhangUMLGedreht: — portrait page, image rotated 90° CCW
 	appendixTitle          string
 	nextCodeBlockAppendix  bool // set by @AnhangCode: — next non-diagram code block → appendix
 	codeBlockAppendixTitle string
@@ -122,6 +123,7 @@ func RenderAST(doc ast.Node, content []byte, r *IHKRenderer) error {
 					state.nextDiagramCaption = ""
 					state.nextCodeIsAppendix = false
 					state.nextAppendixLandscape = false
+					state.nextAppendixRotated = false
 				}
 				if err == nil {
 					switch {
@@ -130,15 +132,24 @@ func RenderAST(doc ast.Node, content []byte, r *IHKRenderer) error {
 						state.nextDiagramLandscape = false
 						state.nextDiagramCaption = ""
 					case state.nextCodeIsAppendix:
-						if state.nextAppendixLandscape {
+						switch {
+						case state.nextAppendixLandscape:
 							r.AddLandscapeAppendix(state.appendixTitle + " | " + imgPath)
 							state.nextAppendixLandscape = false
-						} else {
+						case state.nextAppendixRotated:
+							r.AddRotatedUMLAppendix(state.appendixTitle, imgPath)
+							state.nextAppendixRotated = false
+						default:
 							r.AddAppendix(state.appendixTitle + " | " + imgPath)
 						}
 						state.nextCodeIsAppendix = false
 					default:
-						r.RenderImage(imgPath, "Diagram ("+lang+")")
+						caption := state.nextDiagramCaption
+						if caption == "" {
+							caption = "Diagram (" + lang + ")"
+						}
+						state.nextDiagramCaption = ""
+						r.RenderImage(imgPath, caption)
 					}
 					return ast.WalkSkipChildren, nil
 				}
@@ -287,6 +298,15 @@ func handleDirectives(text string, state *parserState, r *IHKRenderer) bool {
 			state.nextAppendixLandscape = true
 			state.appendixTitle = strings.TrimSpace(strings.TrimPrefix(line, "@AnhangUMLQuer:"))
 			handled = true
+		case strings.HasPrefix(line, "@AnhangUMLGedreht:"):
+			// Portrait page, image rotated 90° CCW — long axis runs top-to-bottom.
+			state.nextCodeIsAppendix = true
+			state.nextAppendixRotated = true
+			state.appendixTitle = strings.TrimSpace(strings.TrimPrefix(line, "@AnhangUMLGedreht:"))
+			handled = true
+		case strings.HasPrefix(line, "@AnhangBildGedreht:"):
+			r.AddRotatedImageAppendix(strings.TrimSpace(strings.TrimPrefix(line, "@AnhangBildGedreht:")))
+			handled = true
 		case strings.HasPrefix(line, "@AnhangUML:"):
 			state.nextCodeIsAppendix = true
 			state.appendixTitle = strings.TrimSpace(strings.TrimPrefix(line, "@AnhangUML:"))
@@ -307,6 +327,10 @@ func handleDirectives(text string, state *parserState, r *IHKRenderer) bool {
 			state.nextDiagramLandscape = true
 			state.nextDiagramCaption = strings.TrimSpace(strings.TrimPrefix(line, "@DiagrammQuer:"))
 			handled = true
+		case strings.HasPrefix(line, "@Diagramm:"):
+			// Portrait inline diagram — rendered at current position via RenderImage.
+			state.nextDiagramCaption = strings.TrimSpace(strings.TrimPrefix(line, "@Diagramm:"))
+			handled = true
 		}
 	}
 	return handled
@@ -3,6 +3,7 @@ package main
 import (
 	"fmt"
 	"log"
+	"sort"
 	"strconv"
 	"strings"

@@ -30,8 +31,19 @@ func (r *IHKRenderer) RenderHeader(level int, title string) {
 		// Major sections start on a new page per IHK convention.
 		r.pdf.AddPage()
 	} else if !r.isAtPageTop() {
-		// IHK: two blank lines before a heading that is not at the page top.
-		r.pdf.Ln(dinSpaceBeforeHeading)
+		// Require enough space for: before-spacing + heading + after-spacing + 3 body
+		// lines. If the remaining page space is too tight, start a new page instead
+		// of leaving an orphaned heading at the bottom.
+		const minBodyLines = 3
+		needed := dinSpaceBeforeHeading + dinLineHtHeading + dinSpaceAfterHeading + minBodyLines*dinLineHtBody
+		_, pageH := r.pdf.GetPageSize()
+		_, _, _, bm := r.pdf.GetMargins()
+		if r.pdf.GetY()+needed > pageH-bm {
+			r.pdf.AddPage()
+		} else {
+			// IHK: two blank lines before a heading that is not at the page top.
+			r.pdf.Ln(dinSpaceBeforeHeading)
+		}
 	}

 	r.RecordHeader(level, title)
@@ -229,9 +241,93 @@ func (r *IHKRenderer) wrapCellSpans(spans []InlineSpan, maxWidth float64, forceB
 	return lines
 }

+// computeColWidths measures the natural content width of each column and
+// returns per-column widths that sum to at most uw.
+//
+// When columns do not fit at natural width, narrow columns are protected:
+// processing from smallest to largest, each column receives its natural width
+// if a fair share of the remaining space allows it; only the widest columns
+// absorb the compression. This prevents narrow ID/label columns from being
+// crushed to illegibility by a single very wide content column.
+func (r *IHKRenderer) computeColWidths(data [][][]InlineSpan, numCols int, uw float64) []float64 {
+	const padding = 4.0 // 2 mm left + 2 mm right per cell
+	natural := make([]float64, numCols)
+
+	for rowIdx, row := range data {
+		isHeader := rowIdx == 0
+		for j := 0; j < numCols; j++ {
+			if j >= len(row) {
+				continue
+			}
+			w := padding
+			for _, span := range row[j] {
+				if span.Code {
+					r.pdf.SetFont("Courier", "", dinFontCaption)
+				} else {
+					r.pdf.SetFont("Helvetica", fontStyle(span.Bold || isHeader, span.Italic), dinFontCaption)
+				}
+				w += r.pdf.GetStringWidth(r.tr(span.Text))
+			}
+			if w > natural[j] {
+				natural[j] = w
+			}
+		}
+	}
+
+	total := 0.0
+	for _, w := range natural {
+		total += w
+	}
+
+	if total <= uw {
+		// Scale all columns up proportionally so the table always fills the full
+		// usable width. Without this, tables with short content leave a blank gap
+		// on the right and borders don't align with the page layout.
+		scale := uw / total
+		for j := range natural {
+			natural[j] *= scale
+		}
+		return natural
+	}
+
+	// total > uw: scale down, but protect narrow columns from being crushed.
+	// Sort column indices from narrowest to widest natural width.
+	// Give each narrow column its full natural width while possible;
+	// the remaining (wider) columns share whatever space is left, proportionally.
+	order := make([]int, numCols)
+	for i := range order {
+		order[i] = i
+	}
+	sort.Slice(order, func(a, b int) bool { return natural[order[a]] < natural[order[b]] })
+
+	result := make([]float64, numCols)
+	remaining := uw
+
+	for pass, j := range order {
+		colsLeft := numCols - pass
+		fairShare := remaining / float64(colsLeft)
+		if natural[j] <= fairShare {
+			result[j] = natural[j]
+			remaining -= natural[j]
+		} else {
+			// This and all following (wider) columns share the remaining space
+			// proportionally to their natural widths.
+			naturalTail := 0.0
+			for _, k := range order[pass:] {
+				naturalTail += natural[k]
+			}
+			for _, k := range order[pass:] {
+				result[k] = natural[k] / naturalTail * remaining
+			}
+			break
+		}
+	}
+	return result
+}
+
 // prepareRow wraps each cell's inline spans and returns a tableRowData.
 // If bold is true, all cell text is forced bold (used for the header row).
-func (r *IHKRenderer) prepareRow(rawCells [][]InlineSpan, numCols int, colW, lineHt float64, bold bool) tableRowData {
+func (r *IHKRenderer) prepareRow(rawCells [][]InlineSpan, numCols int, colWidths []float64, lineHt float64, bold bool) tableRowData {
 	cells := make([][][]InlineSpan, numCols)
 	maxLines := 0
 	for j := 0; j < numCols; j++ {
@@ -239,7 +335,11 @@ func (r *IHKRenderer) prepareRow(rawCells [][]InlineSpan, numCols int, colW, lin
 		if j < len(rawCells) {
 			spans = rawCells[j]
 		}
-		lines := r.wrapCellSpans(spans, colW-2, bold)
+		cw := 0.0
+		if j < len(colWidths) {
+			cw = colWidths[j]
+		}
+		lines := r.wrapCellSpans(spans, cw-2, bold)
 		cells[j] = lines
 		if len(lines) > maxLines {
 			maxLines = len(lines)
@@ -254,7 +354,15 @@ func (r *IHKRenderer) prepareRow(rawCells [][]InlineSpan, numCols int, colW, lin
 // drawRow renders a pre-computed row at the current Y position.
 // Cell borders are drawn as rectangles so all cells share a uniform height.
 // Header cells are rendered bold and centred; body cells honour per-span formatting.
-func (r *IHKRenderer) drawRow(row tableRowData, numCols int, colW, lineHt float64, isHeader bool) {
+func (r *IHKRenderer) drawRow(row tableRowData, numCols int, colWidths []float64, lineHt float64, isHeader bool) {
+	// Disable fpdf's auto page break for the duration of the row so that
+	// CellFormat calls inside a row can never trigger a mid-row page break.
+	// (Rect already doesn't trigger page breaks, but CellFormat does — this
+	// makes the two consistent and prevents row-content from appearing on the
+	// wrong page relative to the row background.)
+	r.pdf.SetAutoPageBreak(false, 0)
+	defer r.pdf.SetAutoPageBreak(true, dinMarginBottom)
+
 	startY := r.pdf.GetY()
 	lm, _, _, _ := r.pdf.GetMargins()

@@ -264,14 +372,25 @@ func (r *IHKRenderer) drawRow(row tableRowData, numCols int, colW, lineHt float6
 		r.pdf.SetFillColor(255, 255, 255)
 	}

+	// Precompute cumulative x positions for each column.
+	xPos := make([]float64, numCols+1)
+	xPos[0] = lm
+	for j, cw := range colWidths {
+		xPos[j+1] = xPos[j] + cw
+	}
+
 	// Draw all cell backgrounds and borders first (uniform height via Rect).
 	for j := 0; j < numCols; j++ {
-		r.pdf.Rect(lm+float64(j)*colW, startY, colW, row.height, "FD")
+		r.pdf.Rect(xPos[j], startY, colWidths[j], row.height, "FD")
 	}

 	// Render text on top, line by line per cell.
 	for j, cellLines := range row.cells {
-		x := lm + float64(j)*colW
+		x := xPos[j]
+		cw := 0.0
+		if j < len(colWidths) {
+			cw = colWidths[j]
+		}
 		for k, spanLine := range cellLines {
 			y := startY + float64(k)*lineHt
 			if isHeader {
@@ -282,7 +401,7 @@ func (r *IHKRenderer) drawRow(row tableRowData, numCols int, colW, lineHt float6
 				}
 				r.pdf.SetFont("Helvetica", "B", dinFontCaption)
 				r.pdf.SetXY(x+1, y)
-				r.pdf.CellFormat(colW-2, lineHt, r.tr(plainText), "", 0, "C", false, 0, "")
+				r.pdf.CellFormat(cw-2, lineHt, r.tr(plainText), "", 0, "C", false, 0, "")
 			} else {
 				// Body: render each span with its own font, left-aligned.
 				r.pdf.SetXY(x+1, y)
@@ -330,17 +449,17 @@ func (r *IHKRenderer) renderTableBody(data [][][]InlineSpan, label string) {
 	}

 	uw := r.usableWidth()
-	colW := uw / float64(numCols)
+	colWidths := r.computeColWidths(data, numCols, uw)
 	lineHt := dinLineHtCaption + 2

 	_, pageH := r.pdf.GetPageSize()
 	_, _, _, bm := r.pdf.GetMargins()

 	// Pre-compute all rows so we know heights before rendering.
-	headerRow := r.prepareRow(header, numCols, colW, lineHt, true)
+	headerRow := r.prepareRow(header, numCols, colWidths, lineHt, true)
 	bodyRows := make([]tableRowData, len(data)-1)
 	for i := 1; i < len(data); i++ {
-		bodyRows[i-1] = r.prepareRow(data[i], numCols, colW, lineHt, false)
+		bodyRows[i-1] = r.prepareRow(data[i], numCols, colWidths, lineHt, false)
 	}

 	renderHeader := func(continued bool) {
@@ -352,7 +471,24 @@ func (r *IHKRenderer) renderTableBody(data [][][]InlineSpan, label string) {
 			r.pdf.SetFont("Helvetica", "B", dinFontCaption)
 			r.pdf.CellFormat(0, lineHt, r.tr(title), "", 1, "L", false, 0, "")
 		}
-		r.drawRow(headerRow, numCols, colW, lineHt, true)
+		r.drawRow(headerRow, numCols, colWidths, lineHt, true)
+	}
+
+	// Ensure label + header + at least the first body row fit on the current page
+	// before starting to render. Without this check, drawRow can start rendering
+	// the header near the bottom of the page and the background rect (drawn by
+	// Rect, which doesn't trigger auto page break) ends up on a different page
+	// from the cell text (drawn by CellFormat, which used to trigger page breaks).
+	labelH := 0.0
+	if label != "" {
+		labelH = lineHt
+	}
+	minH := labelH + headerRow.height
+	if len(bodyRows) > 0 {
+		minH += bodyRows[0].height
+	}
+	if r.pdf.GetY()+minH > pageH-bm {
+		r.pdf.AddPage()
 	}

 	renderHeader(false)
@@ -362,7 +498,7 @@ func (r *IHKRenderer) renderTableBody(data [][][]InlineSpan, label string) {
 			r.pdf.AddPage()
 			renderHeader(true)
 		}
-		r.drawRow(row, numCols, colW, lineHt, false)
+		r.drawRow(row, numCols, colWidths, lineHt, false)
 	}
 	r.pdf.Ln(dinSpaceAfterParagraph)
 }
@@ -2,7 +2,12 @@ package main

 import (
 	"fmt"
+	"image"
+	"image/draw"
+	_ "image/jpeg"
+	"image/png"
 	"log"
+	"os"
 	"sort"

 	"github.com/go-pdf/fpdf"
@@ -142,7 +147,7 @@ func (r *IHKRenderer) RenderAppendices() {
 	r.pdf.SetFont("Helvetica", "", dinFontBody)
 	for i, app := range r.appendices {
 		r.pdf.CellFormat(0, dinLineHtBody,
-			r.tr(fmt.Sprintf("Anlage %d: %s", i+1, app.Title)), "", 1, "L", false, 0, "")
+			r.tr(fmt.Sprintf("Anlage %s: %s", toRoman(i+1), app.Title)), "", 1, "L", false, 0, "")
 	}

 	// Save portrait dimensions and standard margins for post-landscape restoration.
@@ -164,12 +169,16 @@ func (r *IHKRenderer) RenderAppendices() {

 		r.pdf.SetFont("Helvetica", "B", dinFontBody)
 		r.pdf.CellFormat(0, dinLineHtBody,
-			r.tr(fmt.Sprintf("Anlage %d: %s", i+1, app.Title)), "", 1, "L", false, 0, "")
+			r.tr(fmt.Sprintf("Anlage %s: %s", toRoman(i+1), app.Title)), "", 1, "L", false, 0, "")
 		r.pdf.Ln(dinSpaceAfterHeading)

 		switch app.Kind {
 		case AppendixKindImage:
-			r.renderAppendixImage(app.Path)
+			if app.Rotated {
+				r.renderAppendixImageRotated(app.Path)
+			} else {
+				r.renderAppendixImage(app.Path)
+			}
 		case AppendixKindTable:
 			r.renderTableBody(app.TableData, "")
 		case AppendixKindCode:
@@ -215,6 +224,91 @@ func (r *IHKRenderer) renderAppendixImage(path string) {
 		fpdf.ImageOptions{ReadDpi: true}, 0, "")
 }

+// renderAppendixImageRotated places an image on a portrait page rotated 90° CW.
+// The image is pre-rotated in memory so that a wide (landscape-ratio) diagram
+// fills the page height. The reader tilts the page 90° CW to read it normally.
+func (r *IHKRenderer) renderAppendixImageRotated(path string) {
+	rotatedPath, err := rotateImageCW(path)
+	if err != nil {
+		log.Printf("warning: could not rotate image %q: %v — falling back to normal", path, err)
+		r.renderAppendixImage(path)
+		return
+	}
+
+	r.renderAppendixImageWithPath(rotatedPath)
+}
+
+// rotateImageCW decodes a PNG/JPEG from disk, rotates it 90° clockwise, writes
+// the result to a temp file, and returns the temp file path.
+// The caller owns the temp file (it is left on disk; fpdf reads it lazily).
+func rotateImageCW(src string) (string, error) {
+	f, err := os.Open(src)
+	if err != nil {
+		return "", err
+	}
+	defer f.Close()
+
+	img, _, err := image.Decode(f)
+	if err != nil {
+		return "", err
+	}
+
+	b := img.Bounds()
+	// 90° CW: new width = old height, new height = old width.
+	rotated := image.NewRGBA(image.Rect(0, 0, b.Max.Y-b.Min.Y, b.Max.X-b.Min.X))
+	draw.Draw(rotated, rotated.Bounds(), image.White, image.Point{}, draw.Src)
+	for y := b.Min.Y; y < b.Max.Y; y++ {
+		for x := b.Min.X; x < b.Max.X; x++ {
+			// 90° CW: new(newW-1-y, x) = old(x, y)
+			rotated.Set(b.Max.Y-1-y, x-b.Min.X, img.At(x, y))
+		}
+	}
+
+	tmp, err := os.CreateTemp("", "ihk_rotated_*.png")
+	if err != nil {
+		return "", err
+	}
+	defer tmp.Close()
+
+	if err := png.Encode(tmp, rotated); err != nil {
+		os.Remove(tmp.Name())
+		return "", err
+	}
+	return tmp.Name(), nil
+}
+
+// renderAppendixImageWithPath is identical to renderAppendixImage but accepts
+// an arbitrary path (used for pre-rotated temp files).
+func (r *IHKRenderer) renderAppendixImageWithPath(path string) {
+	info := r.ensureImageRegistered(path)
+	if info == nil {
+		r.pdf.CellFormat(0, dinLineHtBody, r.tr("[Image could not be loaded: "+path+"]"),
+			"1", 1, "C", false, 0, "")
+		return
+	}
+
+	_, pageH := r.pdf.GetPageSize()
+	lm, _, _, bm := r.pdf.GetMargins()
+	uw := r.usableWidth()
+	availH := pageH - r.pdf.GetY() - bm - 10
+
+	imgW := info.Width() * ptToMM
+	imgH := info.Height() * ptToMM
+
+	displayW := uw
+	displayH := imgH * (displayW / imgW)
+	if displayH > availH {
+		scale := availH / displayH
+		displayH = availH
+		displayW = displayW * scale
+	}
+
+	posX := lm + (uw-displayW)/2
+	r.pdf.ImageOptions(path, posX, r.pdf.GetY(), displayW, displayH, false,
+		fpdf.ImageOptions{ReadDpi: true}, 0, "")
+	r.pdf.SetY(r.pdf.GetY() + displayH + 2)
+}
+
 // RenderAbbreviations renders the list of abbreviations from the YAML config.
 // It is placed after the TOC and uses Roman page numbering.
 func (r *IHKRenderer) RenderAbbreviations() {
@@ -55,6 +55,7 @@ const (
 type Appendix struct {
 	Kind      AppendixKind
 	Landscape bool // true → render on a landscape A4 page (15 mm symmetric margins)
+	Rotated   bool // true → portrait page, image rotated 90° CCW so long axis runs top-to-bottom
 	Title     string
 	Path      string           // image path (Kind == AppendixKindImage)
 	TableData [][][]InlineSpan // table rows (Kind == AppendixKindTable)
@@ -194,6 +195,35 @@ func (r *IHKRenderer) AddCodeAppendix(title, lang, code string) {
 	})
 }

+// AddRotatedImageAppendix registers an image annex rendered on a portrait A4 page
+// with the image rotated 90° CCW, so a wide (landscape-ratio) diagram fills the
+// full page height when the reader tilts the page 90° clockwise.
+// Format: "Title | /path/to/image"
+func (r *IHKRenderer) AddRotatedImageAppendix(titlePath string) {
+	parts := strings.SplitN(titlePath, "|", 2)
+	if len(parts) < 2 {
+		log.Printf("warning: @AnhangBildGedreht directive missing '|' separator: %q", titlePath)
+		return
+	}
+	r.appendices = append(r.appendices, Appendix{
+		Kind:    AppendixKindImage,
+		Rotated: true,
+		Title:   strings.TrimSpace(parts[0]),
+		Path:    strings.TrimSpace(parts[1]),
+	})
+}
+
+// AddRotatedUMLAppendix registers a UML/diagram annex (code block) rendered on a
+// portrait A4 page with the diagram image rotated 90° CCW.
+func (r *IHKRenderer) AddRotatedUMLAppendix(title, imgPath string) {
+	r.appendices = append(r.appendices, Appendix{
+		Kind:    AppendixKindImage,
+		Rotated: true,
+		Title:   title,
+		Path:    imgPath,
+	})
+}
+
 // AddLandscapeAppendix registers an image annex in "Title | /path/to/image" format
 // that will be rendered on a landscape A4 page with 15 mm symmetric margins.
 func (r *IHKRenderer) AddLandscapeAppendix(titlePath string) {