Adding resvg options

README.md

@@ -101,7 +101,7 @@ $ RUSTFLAGS="--print=native-static-libs" cargo build --release
 
 ## TODO
 
-- Expand API to support the avaliable `resvg_options`
+- Rewrite as pure Go
 
 ## About
 

resvg.go

@@ -1,4 +1,6 @@
-// Package resvg is a wrapper around rust's resvg c-api crate.
+// Package resvg is a wrapper around rust's [resvg] c-api crate.
+//
+// [resvg]: https://github.com/RazrFalcon/resvg
 package resvg
 
 /*
@@ -10,13 +12,11 @@ package resvg
 #cgo linux,arm LDFLAGS: -L${SRCDIR}/libresvg/linux_arm -lresvg -lm
 #cgo windows,amd64 LDFLAGS: -L${SRCDIR}/libresvg/windows_amd64 -lresvg -lm -lkernel32 -ladvapi32 -lbcrypt -lntdll -luserenv -lws2_32
 
+#include <stdlib.h>
 #include <errno.h>
 #include "resvg.h"
 
-resvg_render_tree* parse(_GoBytes_ data) {
-	// create options
-	resvg_options* opts = resvg_options_create();
-	resvg_options_load_system_fonts(opts);
+resvg_render_tree* parse(_GoBytes_ data, resvg_options* opts) {
 	// parse
 	resvg_render_tree* tree;
 	errno = resvg_parse_tree_from_data(data.p, data.n, opts, &tree);
@@ -37,12 +37,131 @@ import (
 	"fmt"
 	"image"
 	"image/color"
+	"strings"
 	"syscall"
+	"unsafe"
 )
 
 // Render renders svg data as a RGBA image.
-func Render(data []byte) (*image.RGBA, error) {
-	tree, errno := C.parse(data)
+func Render(data []byte, opts ...Option) (*image.RGBA, error) {
+	return New(opts...).Render(data)
+}
+
+// Resvg wraps the [resvg c-api].
+//
+// [resvg c-api]: https://github.com/RazrFalcon/resvg
+type Resvg struct {
+	LoadSystemFonts bool
+	ResourcesDir    string
+	DPI             float32
+	FontFamily      string
+	FontSize        float32
+	SerifFamily     string
+	SansSerifFamily string
+	CursiveFamily   string
+	FantasyFamily   string
+	MonospaceFamily string
+	Languages       []string
+	ShapeRendering  ShapeRendering
+	TextRendering   TextRendering
+	ImageRendering  ImageRendering
+	Fonts           [][]byte
+	FontFiles       []string
+}
+
+// New creates a new resvg.
+func New(opts ...Option) *Resvg {
+	r := &Resvg{
+		LoadSystemFonts: true,
+		ShapeRendering:  ShapeRenderingNotSet,
+		TextRendering:   TextRenderingNotSet,
+		ImageRendering:  ImageRenderingNotSet,
+	}
+	for _, o := range opts {
+		o(r)
+	}
+	return r
+}
+
+// buildOpts builds the resvg options.
+func (r *Resvg) buildOpts() *C.resvg_options {
+	opts := C.resvg_options_create()
+	if r.LoadSystemFonts {
+		C.resvg_options_load_system_fonts(opts)
+	}
+	if r.ResourcesDir != "" {
+		s := C.CString(r.ResourcesDir)
+		C.resvg_options_set_resources_dir(opts, s)
+		C.free(unsafe.Pointer(s))
+	}
+	if r.DPI != 0.0 {
+		C.resvg_options_set_dpi(opts, C.float(r.DPI))
+	}
+	if r.FontFamily != "" {
+		s := C.CString(r.FontFamily)
+		C.resvg_options_set_font_family(opts, s)
+		C.free(unsafe.Pointer(s))
+	}
+	if r.FontSize != 0.0 {
+		C.resvg_options_set_font_size(opts, C.float(r.FontSize))
+	}
+	if r.SerifFamily != "" {
+		s := C.CString(r.SerifFamily)
+		C.resvg_options_set_serif_family(opts, s)
+		C.free(unsafe.Pointer(s))
+	}
+	if r.SansSerifFamily != "" {
+		s := C.CString(r.SansSerifFamily)
+		C.resvg_options_set_sans_serif_family(opts, s)
+		C.free(unsafe.Pointer(s))
+	}
+	if r.CursiveFamily != "" {
+		s := C.CString(r.CursiveFamily)
+		C.resvg_options_set_cursive_family(opts, s)
+		C.free(unsafe.Pointer(s))
+	}
+	if r.FantasyFamily != "" {
+		s := C.CString(r.FantasyFamily)
+		C.resvg_options_set_fantasy_family(opts, s)
+		C.free(unsafe.Pointer(s))
+	}
+	if r.MonospaceFamily != "" {
+		s := C.CString(r.MonospaceFamily)
+		C.resvg_options_set_monospace_family(opts, s)
+		C.free(unsafe.Pointer(s))
+	}
+	if len(r.Languages) != 0 {
+		s := C.CString(strings.Join(r.Languages, ","))
+		C.resvg_options_set_languages(opts, s)
+		C.free(unsafe.Pointer(s))
+	}
+	if r.ShapeRendering != ShapeRenderingNotSet {
+		C.resvg_options_set_shape_rendering_mode(opts, C.resvg_shape_rendering(r.ShapeRendering))
+	}
+	if r.TextRendering != TextRenderingNotSet {
+		C.resvg_options_set_text_rendering_mode(opts, C.resvg_text_rendering(r.TextRendering))
+	}
+	if r.ImageRendering != ImageRenderingNotSet {
+		C.resvg_options_set_image_rendering_mode(opts, C.resvg_image_rendering(r.ImageRendering))
+	}
+	for _, font := range r.Fonts {
+		s := C.CString(string(font))
+		C.resvg_options_load_font_data(opts, s, C.ulong(len(font)))
+		C.free(unsafe.Pointer(s))
+	}
+	for _, fontFile := range r.FontFiles {
+		if fontFile != "" {
+			s := C.CString(fontFile)
+			C.resvg_options_load_font_file(opts, s)
+			C.free(unsafe.Pointer(s))
+		}
+	}
+	return opts
+}
+
+// Render renders svg data as a RGBA image.
+func (r *Resvg) Render(data []byte) (*image.RGBA, error) {
+	tree, errno := C.parse(data, r.buildOpts())
 	if errno != nil {
 		return nil, NewParseError(errno)
 	}
@@ -63,6 +182,38 @@ func Render(data []byte) (*image.RGBA, error) {
 	return img, nil
 }
 
+// ShapeRendering is the shape rendering mode.
+type ShapeRendering int
+
+// Shape rendering modes.
+const (
+	ShapeRenderingOptimizeSpeed      ShapeRendering = C.RESVG_SHAPE_RENDERING_OPTIMIZE_SPEED
+	ShapeRenderingCrispEdges         ShapeRendering = C.RESVG_SHAPE_RENDERING_CRISP_EDGES
+	ShapeRenderingGeometricPrecision ShapeRendering = C.RESVG_SHAPE_RENDERING_GEOMETRIC_PRECISION
+	ShapeRenderingNotSet             ShapeRendering = 0xff
+)
+
+// TextRendering is the text rendering mode.
+type TextRendering int
+
+// Text rendering modes.
+const (
+	TextRenderingOptimizeSpeed      TextRendering = C.RESVG_TEXT_RENDERING_OPTIMIZE_SPEED
+	TextRenderingOptimizeLegibility TextRendering = C.RESVG_TEXT_RENDERING_OPTIMIZE_LEGIBILITY
+	TextRenderingGeometricPrecision TextRendering = C.RESVG_TEXT_RENDERING_GEOMETRIC_PRECISION
+	TextRenderingNotSet             TextRendering = 0xff
+)
+
+// ImageRendering is the image rendering mode.
+type ImageRendering int
+
+// Image rendering modes.
+const (
+	ImageRenderingOptimizeQuality ImageRendering = C.RESVG_IMAGE_RENDERING_OPTIMIZE_QUALITY
+	ImageRenderingOptimizeSpeed   ImageRendering = C.RESVG_IMAGE_RENDERING_OPTIMIZE_SPEED
+	ImageRenderingNotSet          ImageRendering = 0xff
+)
+
 // ParseError is a parse error.
 type ParseError int
 
@@ -97,3 +248,111 @@ func (err ParseError) Error() string {
 	}
 	return ""
 }
+
+// Option is a resvg rendering option.
+type Option func(*Resvg)
+
+// WithLoadSystemFonts is a resvg option to load system fonts.
+func WithLoadSystemFonts(loadSystemFonts bool) Option {
+	return func(r *Resvg) {
+		r.LoadSystemFonts = loadSystemFonts
+	}
+}
+
+// WithResourcesDir is a resvg option to set the resources dir.
+func WithResourcesDir(resourcesDir string) Option {
+	return func(r *Resvg) {
+		r.ResourcesDir = resourcesDir
+	}
+}
+
+// WithDPI is a resvg option to set the DPI.
+func WithDPI(dpi float32) Option {
+	return func(r *Resvg) {
+		r.DPI = dpi
+	}
+}
+
+// WithFontFamily is a resvg option to set the font family.
+func WithFontFamily(fontFamily string) Option {
+	return func(r *Resvg) {
+		r.FontFamily = fontFamily
+	}
+}
+
+// WithFontSize is a resvg option to set the font size.
+func WithFontSize(fontSize float32) Option {
+	return func(r *Resvg) {
+		r.FontSize = fontSize
+	}
+}
+
+// WithSerifFamily is a resvg option to set the serif family.
+func WithSerifFamily(serifFamily string) Option {
+	return func(r *Resvg) {
+		r.SerifFamily = serifFamily
+	}
+}
+
+// WithCursiveFamily is a resvg option to set the cursive family.
+func WithCursiveFamily(cursiveFamily string) Option {
+	return func(r *Resvg) {
+		r.CursiveFamily = cursiveFamily
+	}
+}
+
+// WithFantasyFamily is a resvg option to set the fantasy family.
+func WithFantasyFamily(fantasyFamily string) Option {
+	return func(r *Resvg) {
+		r.FantasyFamily = fantasyFamily
+	}
+}
+
+// WithMonospaceFamily is a resvg option to set the monospace family.
+func WithMonospaceFamily(monospaceFamily string) Option {
+	return func(r *Resvg) {
+		r.MonospaceFamily = monospaceFamily
+	}
+}
+
+// WithLanguages is a resvg option to set the languages.
+func WithLanguages(languages ...string) Option {
+	return func(r *Resvg) {
+		r.Languages = languages
+	}
+}
+
+// WithShapeRendering is a resvg option to set the shape rendering mode.
+func WithShapeRendering(shapeRendering ShapeRendering) Option {
+	return func(r *Resvg) {
+		r.ShapeRendering = shapeRendering
+	}
+}
+
+// WithTextRendering is a resvg option to set the text rendering mode.
+func WithTextRendering(textRendering TextRendering) Option {
+	return func(r *Resvg) {
+		r.TextRendering = textRendering
+	}
+}
+
+// WithImageRendering is a resvg option to set the image rendering mode.
+func WithImageRendering(imageRendering ImageRendering) Option {
+	return func(r *Resvg) {
+		r.ImageRendering = imageRendering
+	}
+}
+
+// WithFonts is a resvg option to set font data.
+func WithFonts(fonts ...[]byte) Option {
+	return func(r *Resvg) {
+		r.Fonts = fonts
+	}
+}
+
+// WithFontFiles is a resvg option to set font files.
+func WithFontFiles(fontFiles ...string) Option {
+	return func(r *Resvg) {
+		r.FontFiles = fontFiles
+	}
+}