Add SVG support for currentColor

The currentColor special value for the fill and stroke attributes allows
an image to follow the same foreground color of the surounding text.

7 files changed, 39 insertions, 19 deletions

diff --git a/src/dicache.c b/src/dicache.c
index 1419ff7a..c9f4067b 100644
--- a/src/dicache.c
+++ b/src/dicache.c
@@ -2,6 +2,7 @@
  * File: dicache.c
  *
  * Copyright 2000-2007 Jorge Arellano Cid <jcid@dillo.org>
+ * Copyright 2024 Rodrigo Arias Mallo <rodarima@gmail.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -353,7 +354,7 @@ void a_Dicache_close(DilloUrl *url, int version, CacheClient_t *Client)
 /* ------------------------------------------------------------------------- */
 
 /**
- * Generic MIME handler for GIF, JPEG and PNG.
+ * Generic MIME handler for GIF, JPEG, PNG and SVG.
  * Sets a_Dicache_callback as the cache-client,
  * and also sets the image decoder.
  *
@@ -372,7 +373,7 @@ static void *Dicache_image(int ImgType, const char *MimeType, void *Ptr,
 
    if (!web->Image) {
       web->Image =
-         a_Image_new_with_dw(web->bw->render_layout, NULL, web->bgColor);
+         a_Image_new_with_dw(web->bw->render_layout, NULL, web->bgColor, 0);
       a_Image_ref(web->Image);
    }
 
diff --git a/src/html.cc b/src/html.cc
index a55fd2a8..4e2b73d1 100644
--- a/src/html.cc
+++ b/src/html.cc
@@ -2149,13 +2149,16 @@ DilloImage *a_Html_image_new(DilloHtml *html, const char *tag, int tagsize)
 
    dw::Image *dw = new dw::Image(alt_ptr);
    image =
-      a_Image_new(html->dw->getLayout(), (void*)(dw::core::ImgRenderer*)dw, 0);
+      a_Image_new(html->dw->getLayout(), (void*)(dw::core::ImgRenderer*)dw, 0, 0);
    
    a_Image_ref(image);
 
    if (HT2TB(html)->getBgColor())
       image->bg_color = HT2TB(html)->getBgColor()->getColor();
 
+   if (HT2TB(html)->getFgColor())
+      image->fg_color = HT2TB(html)->getFgColor()->getColor();
+
    DilloHtmlImage *hi = dNew(DilloHtmlImage, 1);
    hi->url = url;
    html->images->increase();
diff --git a/src/image.cc b/src/image.cc
index c9862661..ae85569c 100644
--- a/src/image.cc
+++ b/src/image.cc
@@ -31,7 +31,8 @@ using namespace dw::core;
 /**
  * Create and initialize a new image structure.
  */
-DilloImage *a_Image_new(void *layout, void *img_rndr, int32_t bg_color)
+DilloImage *a_Image_new(void *layout, void *img_rndr,
+                        int32_t bg_color, int32_t fg_color)
 {
    DilloImage *Image;
 
@@ -42,6 +43,7 @@ DilloImage *a_Image_new(void *layout, void *img_rndr, int32_t bg_color)
    Image->height = 0;
    Image->dpi = ((Layout *) layout)->dpiX();
    Image->bg_color = bg_color;
+   Image->fg_color = fg_color;
    Image->ScanNumber = 0;
    Image->BitVec = NULL;
    Image->State = IMG_Empty;
@@ -55,10 +57,10 @@ DilloImage *a_Image_new(void *layout, void *img_rndr, int32_t bg_color)
  * Create and initialize a new image structure with an image widget.
  */
 DilloImage *a_Image_new_with_dw(void *layout, const char *alt_text,
-                                int32_t bg_color)
+                                int32_t bg_color, int32_t fg_color)
 {
    dw::Image *dw = new dw::Image(alt_text);
-   return a_Image_new(layout, (void*)(dw::core::ImgRenderer*)dw, bg_color);
+   return a_Image_new(layout, (void*)(dw::core::ImgRenderer*)dw, bg_color, fg_color);
 }
 
 /**
diff --git a/src/image.hh b/src/image.hh
index a5057227..2dc87ecc 100644
--- a/src/image.hh
+++ b/src/image.hh
@@ -66,6 +66,7 @@ struct _DilloImage {
 
    float dpi;               /**< Dots per inch */
    int32_t bg_color;        /**< Background color */
+   int32_t fg_color;        /**< Foreground color */
    bitvec_t *BitVec;        /**< Bit vector for decoded rows */
    uint_t ScanNumber;       /**< Current decoding scan */
    ImageState State;        /**< Processing status */
@@ -77,9 +78,10 @@ struct _DilloImage {
 /*
  * Function prototypes
  */
-DilloImage *a_Image_new(void *layout, void *img_rndr, int32_t bg_color);
+DilloImage *a_Image_new(void *layout, void *img_rndr,
+                        int32_t bg_color, int32_t fg_color);
 DilloImage *a_Image_new_with_dw(void *layout, const char *alt_text,
-                                int32_t bg_color);
+                                int32_t bg_color, int32_t fg_color);
 void *a_Image_get_dw(DilloImage *Image);
 void a_Image_ref(DilloImage *Image);
 void a_Image_unref(DilloImage *Image);
diff --git a/src/nanosvg.h b/src/nanosvg.h
index e4bfa760..98b06bea 100644
--- a/src/nanosvg.h
+++ b/src/nanosvg.h
@@ -165,15 +165,16 @@ typedef struct NSVGimage
 {
 	float width;				// Width of the image.
 	float height;				// Height of the image.
+	unsigned current_color;			// For "currentColor"
 	NSVGshape* shapes;			// Linked list of shapes in the image.
 } NSVGimage;
 
 // Parses SVG file from a file, returns SVG image as paths.
-NSVGimage* nsvgParseFromFile(const char* filename, const char* units, float dpi);
+NSVGimage* nsvgParseFromFile(const char* filename, const char* units, float dpi, unsigned current_color);
 
 // Parses SVG file from a null terminated string, returns SVG image as paths.
 // Important note: changes the string.
-NSVGimage* nsvgParse(char* input, const char* units, float dpi);
+NSVGimage* nsvgParse(char* input, const char* units, float dpi, unsigned current_color);
 
 // Duplicates a path.
 NSVGpath* nsvgDuplicatePath(NSVGpath* p);
@@ -616,7 +617,7 @@ static void nsvg__curveBounds(float* bounds, float* curve)
 	}
 }
 
-static NSVGparser* nsvg__createParser(void)
+static NSVGparser* nsvg__createParser(unsigned current_color)
 {
 	NSVGparser* p;
 	p = (NSVGparser*)malloc(sizeof(NSVGparser));
@@ -646,6 +647,8 @@ static NSVGparser* nsvg__createParser(void)
 	/* TODO: Let the user change the initial value */
 	p->attr[0].fontSize = 40.0f;
 
+	p->image->current_color = current_color;
+
 	return p;
 
 error:
@@ -1810,7 +1813,7 @@ static int nsvg__parseAttr(NSVGparser* p, const char* name, const char* value)
 			nsvg__parseUrl(attr->fillGradient, value);
 		} else if (strncmp(value, "currentColor", 12) == 0) {
 			attr->hasFill = 1;
-			attr->fillColor = 0; /* TODO: Black by default */
+			attr->fillColor = p->image->current_color;
 		} else {
 			attr->hasFill = 1;
 			attr->fillColor = nsvg__parseColor(value);
@@ -1827,7 +1830,7 @@ static int nsvg__parseAttr(NSVGparser* p, const char* name, const char* value)
 			nsvg__parseUrl(attr->strokeGradient, value);
 		} else if (strncmp(value, "currentColor", 12) == 0) {
 			attr->hasStroke = 1;
-			attr->strokeColor = 0; /* TODO: Black by default */
+			attr->strokeColor = p->image->current_color;
 		} else {
 			attr->hasStroke = 1;
 			attr->strokeColor = nsvg__parseColor(value);
@@ -3097,12 +3100,12 @@ static void nsvg__createGradients(NSVGparser* p)
 	}
 }
 
-NSVGimage* nsvgParse(char* input, const char* units, float dpi)
+NSVGimage* nsvgParse(char* input, const char* units, float dpi, unsigned current_color)
 {
 	NSVGparser* p;
 	NSVGimage* ret = 0;
 
-	p = nsvg__createParser();
+	p = nsvg__createParser(current_color);
 	if (p == NULL) {
 		return NULL;
 	}
@@ -3124,7 +3127,7 @@ NSVGimage* nsvgParse(char* input, const char* units, float dpi)
 	return ret;
 }
 
-NSVGimage* nsvgParseFromFile(const char* filename, const char* units, float dpi)
+NSVGimage* nsvgParseFromFile(const char* filename, const char* units, float dpi, unsigned current_color)
 {
 	FILE* fp = NULL;
 	size_t size;
@@ -3141,7 +3144,7 @@ NSVGimage* nsvgParseFromFile(const char* filename, const char* units, float dpi)
 	if (fread(data, 1, size, fp) != size) goto error;
 	data[size] = '\0';	// Must be null terminated.
 	fclose(fp);
-	image = nsvgParse(data, units, dpi);
+	image = nsvgParse(data, units, dpi, current_color);
 	free(data);
 
 	return image;
diff --git a/src/styleengine.cc b/src/styleengine.cc
index a2cb0c66..6aa99910 100644
--- a/src/styleengine.cc
+++ b/src/styleengine.cc
@@ -765,7 +765,7 @@ void StyleEngine::apply (int i, StyleAttrs *attrs, CssPropertyList *props,
          a_Image_new(layout,
             (void*)attrs->backgroundImage
             ->getMainImgRenderer(),
-            0xffffff);
+            0xffffff, 0x000000);
 
       // we use the pageUrl as requester to prevent cross
       // domain requests as specified in domainrc
diff --git a/src/svg.c b/src/svg.c
index 98fe2ada..5536e9a3 100644
--- a/src/svg.c
+++ b/src/svg.c
@@ -31,6 +31,7 @@ typedef struct {
    DilloUrl *url;               /* Primary Key for the dicache */
    int version;                 /* Secondary Key for the dicache */
    int bgcolor;                 /* Parent widget background color */
+   int fgcolor;                 /* Parent widget foreground color */
 } DilloSvg;
 
 /*
@@ -71,9 +72,16 @@ static void Svg_write(DilloSvg *svg, void *Buf, uint_t BufSize)
    if (strstr(Buf, "</svg>") == NULL)
       return;
 
+   /* Use foreground as the current color, but transform to
+    * nanosvg color format (BGR). */
+   unsigned fg_r = (svg->fgcolor >> 16) & 0xff;
+   unsigned fg_g = (svg->fgcolor >>  8) & 0xff;
+   unsigned fg_b = (svg->fgcolor >>  0) & 0xff;
+   unsigned curcolor = NSVG_RGB(fg_r, fg_g, fg_b);
+
    /* NULL-terminate Buf */
    char *str = dStrndup(Buf, BufSize);
-   NSVGimage *nimg = nsvgParse(str, "px", svg->Image->dpi);
+   NSVGimage *nimg = nsvgParse(str, "px", svg->Image->dpi, curcolor);
    dFree(str);
 
    if (nimg == NULL) {
@@ -149,6 +157,7 @@ void *a_Svg_new(DilloImage *Image, DilloUrl *url, int version)
    svg->url = url;
    svg->version = version;
    svg->bgcolor = Image->bg_color;
+   svg->fgcolor = Image->fg_color;
 
    return svg;
 }