[BUG] Table background color glitch

[ricardogama]

Description

When drawing tables in a consecutive manner, I see some glitches on the background color of some cells.

It seems to happen when a table starts at the very beginning of a page, but it might be coincidence.

Expected Behavior

Every header should be consistent:

Actual Behavior

Glitch observable on pages 14 and 27, and it's consistent every time I run the application and the PDF is generated.

Steps to reproduce the behavior:

1. go run main.go
2. open result.pdf
3. Scroll to page 14

Attachments

package main

import (
	"bytes"
	"fmt"
	"os"

	"github.com/unidoc/unipdf/v3/common/license"
	"github.com/unidoc/unipdf/v3/creator"
	"github.com/unidoc/unipdf/v3/model"
)

var (
	regularFont *model.PdfFont
	boldFont    *model.PdfFont
)

var (
	darkGrayColor  = creator.ColorRGBFromHex("#B3B3B3")
	darkBlueColor  = creator.ColorRGBFromHex("#0D99FF")
	lightBlueColor = creator.ColorRGBFromHex("#BDE3FF")
	lightGrayColor = creator.ColorRGBFromHex("#E6E6E6")
)

func main() {
	if err := license.SetMeteredKey(os.Getenv("UNIDOC_KEY")); err != nil {
		panic(err)
	}

	var err error
	regularFont, err = model.NewStandard14Font("Helvetica")
	if err != nil {
		panic(err)
	}

	boldFont, err = model.NewStandard14Font("Helvetica-Bold")
	if err != nil {
		panic(err)
	}

	c := creator.New()
	c.SetPageMargins(30, 30, 30, 30)

	c.DrawFooter(func(block *creator.Block, args creator.FooterFunctionArgs) {
		p := c.NewStyledParagraph()
		p.SetTextAlignment(creator.TextAlignmentCenter)

		chunk := p.Append(fmt.Sprintf("Page %d of %d", args.PageNum, args.TotalPages))
		chunk.Style.Font = regularFont
		chunk.Style.FontSize = 8
		chunk.Style.Color = creator.ColorBlack

		if err := block.Draw(p); err != nil {
			panic(err)
		}
	})

	for i := 0; i < 200; i++ {
		if err := itemTable(c); err != nil {
			panic(err)
		}
	}

	var content bytes.Buffer
	if err := c.Write(&content); err != nil {
		panic(err)
	}

	f, err := os.Create("./result.pdf")
	if err != nil {
		panic(err)
	}
	_, err = f.Write(content.Bytes())
	if err != nil {
		panic(err)
	}
	err = f.Close()
	if err != nil {
		panic(err)
	}

	fmt.Println("result.pdf created")
}

func newParagraph(c *creator.Creator, font *model.PdfFont, color creator.Color, text string) *creator.StyledParagraph {
	p := c.NewStyledParagraph()
	p.SetMargins(2, 2, 5, 5)
	chunk := p.Append(text)
	chunk.Style.Font = font
	chunk.Style.Color = color
	return p
}

func newCell(t *creator.Table, colspan int, bgColor creator.Color, content creator.VectorDrawable) {
	cell := t.MultiColCell(colspan)
	cell.SetBorder(creator.CellBorderSideAll, creator.CellBorderStyleSingle, 0.3)
	cell.SetHorizontalAlignment(creator.CellHorizontalAlignmentLeft)
	cell.SetBackgroundColor(bgColor)
	if err := cell.SetContent(content); err != nil {
		panic(err)
	}
}

func itemTable(c *creator.Creator) error {
	table := c.NewTable(6)
	table.SetMargins(0, 0, 30, 0)

	drawHeaders := func(text1, text2, text3, text4 string) {
		newCell(table, 1, darkGrayColor, newParagraph(c, boldFont, creator.ColorBlack, text1))
		newCell(table, 2, darkGrayColor, newParagraph(c, boldFont, creator.ColorBlack, text2))
		newCell(table, 1, lightBlueColor, newParagraph(c, boldFont, creator.ColorBlack, text3))
		newCell(table, 2, lightBlueColor, newParagraph(c, regularFont, creator.ColorBlack, text4))
	}

	drawSubHeader := func(text string) {
		newCell(table, 1, lightGrayColor, newParagraph(c, boldFont, creator.ColorBlack, text))
		newCell(table, 2, lightGrayColor, newParagraph(c, boldFont, creator.ColorBlack, ""))
		newCell(table, 1, lightGrayColor, newParagraph(c, boldFont, creator.ColorBlack, ""))
		newCell(table, 2, lightGrayColor, newParagraph(c, boldFont, creator.ColorBlack, ""))
	}

	drawCells := func(text1, text2, text3, text4 string) {
		newCell(table, 1, creator.ColorWhite, newParagraph(c, boldFont, creator.ColorBlack, text1))
		newCell(table, 2, creator.ColorWhite, newParagraph(c, regularFont, creator.ColorBlack, text2))
		newCell(table, 1, creator.ColorWhite, newParagraph(c, boldFont, creator.ColorBlack, text3))
		newCell(table, 2, creator.ColorWhite, newParagraph(c, regularFont, creator.ColorBlack, text4))
	}

	newCell(table, 1, creator.ColorBlack, newParagraph(c, boldFont, creator.ColorWhite, "Product and materials"))
	newCell(table, 2, creator.ColorBlack, newParagraph(c, boldFont, creator.ColorWhite, "Description"))
	newCell(table, 1, darkBlueColor, newParagraph(c, boldFont, creator.ColorWhite, "GSAP"))
	newCell(table, 2, darkBlueColor, newParagraph(c, boldFont, creator.ColorWhite, "*Additional references at the bottom of the deal recap"))

	drawHeaders("Item details", "", "Contract and item number", "12389123987123897")
	drawCells("", "", "", "")
	drawCells("", "", "", "")
	drawCells("", "", "", "")
	drawCells("", "", "", "")

	drawHeaders("Volume", "", "", "")
	drawCells("", "", "", "")
	drawCells("", "", "", "")
	drawCells("", "", "", "")
	drawCells("", "", "", "")
	drawCells("", "", "", "")
	drawCells("", "", "", "")
	drawCells("", "", "", "")
	drawCells("", "", "", "")
	drawCells("", "", "", "")

	drawHeaders("Payment", "", "", "")
	drawCells("", "", "", "")
	drawCells("", "", "", "")
	drawCells("", "", "", "")
	drawCells("", "", "", "")
	drawCells("", "", "", "")

	drawHeaders("Pricing", "", "", "")
	drawCells("", "", "", "")
	drawCells("", "", "", "")

	drawSubHeader("Compulsory fees")
	drawCells("", "", "", "")
	drawCells("", "", "", "")

	drawSubHeader("ENR")
	drawCells("", "", "", "")
	drawCells("", "", "", "")
	drawCells("", "", "", "")

	drawHeaders("Backup depot", "", "Contract and item number", "1000000003-04*")
	drawCells("", "", "", "")
	drawCells("", "", "", "")
	drawCells("", "", "", "")

	drawHeaders("Different volume", "", "", "")
	drawCells("", "", "", "")
	drawCells("", "", "", "")

	drawCells("", "", "", "")
	drawCells("", "", "", "")
	drawCells("", "", "", "")

	return c.Draw(table)
}

result.pdf

[3ace]

@ricardogama Hello, thank you reporting this issue. I can confirm that this is reproducible when table is moved entirely to a new page.

We'll definitely need to fix this. We'll let you ASAP when we've fixed this.

[3ace]

@ricardogama a fix for this issue has been merged in our code base. It should be available with our next release.

[ricardogama]

@3ace Is there any chance you can make a minor release with this fix? It's quite frequent for our business case and we got some complains already, and I see there's another user with the same request: #534

[3ace]

@ricardogama we should have a new version released by the end of this week. I'll inform you later if the new version is released.

[3ace]

@ricardogama we have a new release that should fix this issue. Let us know if you have further issue.

https://github.com/unidoc/unipdf/releases/tag/v3.52.0