]> gitweb.michael.orlitzky.com - libsvgtiny.git/blobdiff - src/svgtiny.c
src/svgtiny.c: set shape opacities from the parser state
[libsvgtiny.git] / src / svgtiny.c
index ee0c59c1eff64a7fa434d22b25d5d1f9dcf7c11f..74ce7eb1775cb92315ac8d7d521ef1533ab2c4a2 100644 (file)
@@ -17,6 +17,8 @@
 #include <dom/dom.h>
 #include <dom/bindings/xml/xmlparser.h>
 
+#include <libcss/libcss.h>
+
 #include "svgtiny.h"
 #include "svgtiny_internal.h"
 
 #define degToRad(angleInDegrees) ((angleInDegrees) * M_PI / 180.0)
 #define radToDeg(angleInRadians) ((angleInRadians) * 180.0 / M_PI)
 
+static svgtiny_code svgtiny_parse_style_element(dom_element *style,
+               struct svgtiny_parse_state state);
+static css_stylesheet *svgtiny_parse_style_inline(const uint8_t *data,
+               size_t len);
+static svgtiny_code svgtiny_preparse_styles(dom_element *svg,
+               struct svgtiny_parse_state state);
 static svgtiny_code svgtiny_parse_svg(dom_element *svg,
                struct svgtiny_parse_state state);
 static svgtiny_code svgtiny_parse_path(dom_element *path,
@@ -610,6 +618,7 @@ svgtiny_code svgtiny_parse(struct svgtiny_diagram *diagram,
                const char *buffer, size_t size, const char *url,
                int viewport_width, int viewport_height)
 {
+       css_error css_code;
        dom_document *document;
        dom_exception exc;
        dom_xml_parser *parser;
@@ -688,13 +697,23 @@ svgtiny_code svgtiny_parse(struct svgtiny_diagram *diagram,
        lwc_string_unref(svg_name_lwc);
        dom_string_unref(svg_name);
 
-       /* get graphic dimensions */
+       /* initialize the state struct with zeros */
        memset(&state, 0, sizeof(state));
+
+       /* get graphic dimensions */
        state.diagram = diagram;
        state.document = document;
        state.viewport_width = viewport_width;
        state.viewport_height = viewport_height;
 
+       /* Initialize CSS context */
+       css_code = css_select_ctx_create(&state.select_ctx);
+       if (css_code != CSS_OK) {
+               dom_node_unref(svg);
+               dom_node_unref(document);
+               return svgtiny_LIBCSS_ERROR;
+       }
+
 #define SVGTINY_STRING_ACTION2(s,n)                                    \
        if (dom_string_create_interned((const uint8_t *) #n,            \
                                       strlen(#n), &state.interned_##s) \
@@ -705,6 +724,19 @@ svgtiny_code svgtiny_parse(struct svgtiny_diagram *diagram,
 #include "svgtiny_strings.h"
 #undef SVGTINY_STRING_ACTION2
 
+       /* Intern SVG's xmlns separately because it's an lwc_string
+        * and not a dom_string. We initialize its pointer to NULL
+        * because the "cleanup:" test to see if it needs to be free'd
+        * looks for NULL. Returning a LIBDOM_ERROR on failure is not
+        * perfect but it's the closest of the available options. */
+       state.interned_svg_xmlns = NULL;
+       if (lwc_intern_string("http://www.w3.org/2000/svg",
+                             26,
+                             &state.interned_svg_xmlns) != lwc_error_ok) {
+               code = svgtiny_LIBDOM_ERROR;
+               goto cleanup;
+       }
+
        svgtiny_parse_position_attributes(svg, state, &x, &y, &width, &height);
        diagram->width = width;
        diagram->height = height;
@@ -718,17 +750,22 @@ svgtiny_code svgtiny_parse(struct svgtiny_diagram *diagram,
        state.ctm.d = 1; /*(float) viewport_height / (float) height;*/
        state.ctm.e = 0; /*x;*/
        state.ctm.f = 0; /*y;*/
-       /*state.style = css_base_style;
-       state.style.font_size.value.length.value = option_font_size * 0.1;*/
        state.fill = 0x000000;
        state.stroke = svgtiny_TRANSPARENT;
        state.stroke_width = 1;
 
        /* parse tree */
-       code = svgtiny_parse_svg(svg, state);
+       code = svgtiny_preparse_styles(svg, state);
+       if (code == svgtiny_OK) {
+               code = svgtiny_parse_svg(svg, state);
+       }
 
        dom_node_unref(svg);
        dom_node_unref(document);
+       css_code = css_select_ctx_destroy(state.select_ctx);
+       if (css_code != CSS_OK) {
+               code = svgtiny_LIBCSS_ERROR;
+       }
 
 cleanup:
        svgtiny_cleanup_state_local(&state);
@@ -737,10 +774,181 @@ cleanup:
                dom_string_unref(state.interned_##s);
 #include "svgtiny_strings.h"
 #undef SVGTINY_STRING_ACTION2
+
+       if (state.interned_svg_xmlns != NULL) {
+               lwc_string_unref(state.interned_svg_xmlns);
+       }
+
        return code;
 }
 
 
+/**
+ * Parse a single <style> element, appending the result to the CSS
+ * select context within the given parser state.
+ */
+svgtiny_code svgtiny_parse_style_element(dom_element *style,
+               struct svgtiny_parse_state state)
+{
+       css_stylesheet *sheet;
+       css_error code;
+       dom_exception exc;
+
+       code = svgtiny_create_stylesheet(&sheet, false);
+       if (code != CSS_OK) {
+               return svgtiny_LIBCSS_ERROR;
+       }
+
+       /* Parse the style element's "media" attribute if it has
+          one. We don't do anything with it right now. */
+       dom_string *media_attr;
+       exc = dom_element_get_attribute(style, state.interned_media,
+                                       &media_attr);
+       if (exc != DOM_NO_ERR) {
+               css_stylesheet_destroy(sheet);
+               return svgtiny_LIBDOM_ERROR;
+       }
+
+       if (media_attr) {
+               /* Here's where we'd actually change the media type if
+                  we were going to use it */
+               dom_string_unref(media_attr);
+       }
+
+       dom_string *data;
+       dom_node_get_text_content(style, &data);
+       if (data == NULL) {
+               /* Empty stylesheet? That's fine. */
+               css_stylesheet_destroy(sheet);
+               return svgtiny_OK;
+       }
+
+       code = css_stylesheet_append_data(sheet,
+                                         (uint8_t *)dom_string_data(data),
+                                         dom_string_byte_length(data));
+       if (code != CSS_OK && code != CSS_NEEDDATA) {
+               dom_string_unref(data);
+               css_stylesheet_destroy(sheet);
+               return svgtiny_LIBCSS_ERROR;
+       }
+
+       code = css_stylesheet_data_done(sheet);
+       if (code != CSS_OK) {
+               dom_string_unref(data);
+               css_stylesheet_destroy(sheet);
+               return svgtiny_LIBCSS_ERROR;
+       }
+
+       code = css_select_ctx_append_sheet(state.select_ctx,
+               sheet,
+               CSS_ORIGIN_AUTHOR,
+               NULL);
+       if (code != CSS_OK) {
+               dom_string_unref(data);
+               return svgtiny_LIBCSS_ERROR;
+       }
+
+       dom_string_unref(data);
+       return svgtiny_OK;
+}
+
+
+/**
+ * Parse the contents of an inline style and return (a pointer to) the
+ * corresponding stylesheet for use with css_select_style(). Returns
+ * NULL if anything goes wrong.
+ */
+css_stylesheet *svgtiny_parse_style_inline(const uint8_t *data,
+               size_t len)
+{
+       css_stylesheet *sheet;
+       css_error code;
+
+       code = svgtiny_create_stylesheet(&sheet, true);
+       if (code != CSS_OK) {
+               return NULL;
+       }
+
+       code = css_stylesheet_append_data(sheet, data, len);
+       if (code != CSS_OK && code != CSS_NEEDDATA) {
+               css_stylesheet_destroy(sheet);
+               return NULL;
+       }
+
+       code = css_stylesheet_data_done(sheet);
+       if (code != CSS_OK) {
+               css_stylesheet_destroy(sheet);
+               return NULL;
+       }
+
+       return sheet;
+}
+
+/**
+ * Parse all <style> elements within a root <svg> element. This
+ * should be called before svgtiny_parse_svg() because that function
+ * makes a single pass through the document and we'd like all style
+ * information to be available during that pass. Specifically, we'd
+ * like a <style> sheet at the end of the document to affect the
+ * rendering of elements at its beginning.
+ *
+ * The element-parsing inner loop here is essentially the same as
+ * that within svgtiny_parse_svg().
+ */
+svgtiny_code svgtiny_preparse_styles(dom_element *svg,
+               struct svgtiny_parse_state state)
+{
+       dom_element *child;
+       dom_exception exc;
+
+       exc = dom_node_get_first_child(svg, (dom_node **) (void *) &child);
+       if (exc != DOM_NO_ERR) {
+               return svgtiny_LIBDOM_ERROR;
+       }
+       while (child != NULL) {
+               dom_element *next;
+               dom_node_type nodetype;
+               svgtiny_code code = svgtiny_OK;
+
+               exc = dom_node_get_node_type(child, &nodetype);
+               if (exc != DOM_NO_ERR) {
+                       dom_node_unref(child);
+                       return svgtiny_LIBDOM_ERROR;
+               }
+               if (nodetype == DOM_ELEMENT_NODE) {
+                       dom_string *nodename;
+                       exc = dom_node_get_node_name(child, &nodename);
+                       if (exc != DOM_NO_ERR) {
+                               dom_node_unref(child);
+                               return svgtiny_LIBDOM_ERROR;
+                       }
+
+                       if (dom_string_caseless_isequal(state.interned_style,
+                                                       nodename)) {
+                               /* We have a <style> element, parse it */
+                               code = svgtiny_parse_style_element(child,
+                                                               state);
+                       }
+
+
+                       dom_string_unref(nodename);
+               }
+               if (code != svgtiny_OK) {
+                       dom_node_unref(child);
+                       return code;
+               }
+               exc = dom_node_get_next_sibling(child,
+                                               (dom_node **) (void *) &next);
+               dom_node_unref(child);
+               if (exc != DOM_NO_ERR) {
+                       return svgtiny_LIBDOM_ERROR;
+               }
+               child = next;
+       }
+
+       return svgtiny_OK;
+}
+
 /**
  * Parse a <svg> or <g> element node.
  */
@@ -1687,9 +1895,6 @@ svgtiny_code svgtiny_parse_text(dom_element *text,
 /*     state.ctm.e = px - state.origin_x; */
 /*     state.ctm.f = py - state.origin_y; */
 
-       /*struct css_style style = state.style;
-       style.font_size.value.length.value *= state.ctm.a;*/
-
         exc = dom_node_get_first_child(text, &child);
        if (exc != DOM_NO_ERR) {
                return svgtiny_LIBDOM_ERROR;
@@ -1819,7 +2024,7 @@ static float _svgtiny_parse_length(const char *s, int viewport_size,
        int num_length = strspn(s, "0123456789+-.");
        const char *unit = s + num_length;
        float n = atof((const char *) s);
-       float font_size = 20; /*css_len2px(&state.style.font_size.value.length, 0);*/
+       float font_size = 20;
 
        UNUSED(state);
 
@@ -1866,6 +2071,22 @@ void svgtiny_parse_paint_attributes(dom_element *node,
 {
        dom_string *attr;
        dom_exception exc;
+       css_error code;
+       uint8_t   fill_opacity_type;
+       css_fixed fill_opacity;
+       uint8_t   stroke_opacity_type;
+       css_fixed stroke_opacity;
+
+       /* We store the result of svgtiny_parse_style_inline() in
+        * inline_sheet, and that function returns NULL on error; in
+        * particular you do not need to css_stylesheet_destroy() the
+        * result if it is NULL, and css_stylesheet_destroy() checks
+        * for that case. */
+       css_stylesheet *inline_sheet = NULL;
+
+       /* Initialize this to NULL for the same reason: so that we can
+        * safely destroy it later even if we never populated it. */
+       css_select_results *styles = NULL;
 
        exc = dom_element_get_attribute(node, state->interned_fill, &attr);
        if (exc == DOM_NO_ERR && attr != NULL) {
@@ -1888,6 +2109,14 @@ void svgtiny_parse_paint_attributes(dom_element *node,
 
        exc = dom_element_get_attribute(node, state->interned_style, &attr);
        if (exc == DOM_NO_ERR && attr != NULL) {
+               /* First parse the style attribute into a libcss stylesheet
+                  in case any of its properties are known to libcss. */
+               inline_sheet = svgtiny_parse_style_inline(
+                                       (uint8_t *)dom_string_data(attr),
+                                       dom_string_byte_length(attr));
+
+               /* Parse any other properties "by hand" until they can
+                  be supported in libcss. */
                char *style = strndup(dom_string_data(attr),
                                      dom_string_byte_length(attr));
                const char *s;
@@ -1920,6 +2149,51 @@ void svgtiny_parse_paint_attributes(dom_element *node,
                free(style);
                dom_string_unref(attr);
        }
+
+       struct dom_element *parent;
+       dom_element_parent_node(node, &parent);
+       if (parent == NULL) {
+               /* This is the root <svg> node, skip it.
+                *
+                * While initialising its selection state, libcss sets its
+                * node_data->bloom pointer using css__get_parent_bloom().
+                * But if there is no parent, that function returns,
+                *
+                *   static css_bloom empty_bloom[CSS_BLOOM_SIZE];
+                *
+                * A problem later arises because when libcss FINALISES its
+                * selection state, it frees node_data->bloom! That obviously
+                * won't work then node has no parent, i.e. if it's the root
+                * <svg> element.
+                */
+               css_stylesheet_destroy(inline_sheet);
+               return;
+       }
+       else {
+               /* We only needed to know if it was NULL */
+               dom_node_unref(parent);
+       }
+
+       code = svgtiny_select_style(state, node, inline_sheet, &styles);
+       css_stylesheet_destroy(inline_sheet);
+       if (code != CSS_OK) {
+               return;
+       }
+
+       fill_opacity_type = css_computed_fill_opacity(
+                               styles->styles[CSS_PSEUDO_ELEMENT_NONE],
+                               &fill_opacity);
+       stroke_opacity_type = css_computed_stroke_opacity(
+                               styles->styles[CSS_PSEUDO_ELEMENT_NONE],
+                               &stroke_opacity);
+       css_select_results_destroy(styles);
+
+       if (fill_opacity_type == CSS_FILL_OPACITY_SET) {
+               state->fill_opacity = FIXTOFLT(fill_opacity);
+       }
+       if (stroke_opacity_type == CSS_STROKE_OPACITY_SET) {
+               state->stroke_opacity = FIXTOFLT(stroke_opacity);
+       }
 }
 
 
@@ -2013,13 +2287,7 @@ void svgtiny_parse_font_attributes(dom_element *node,
 
        for (attr = node->properties; attr; attr = attr->next) {
                if (strcmp((const char *) attr->name, "font-size") == 0) {
-                       /*if (css_parse_length(
-                                       (const char *) attr->children->content,
-                                       &state->style.font_size.value.length,
-                                       true, true)) {
-                               state->style.font_size.size =
-                                               CSS_FONT_SIZE_LENGTH;
-                       }*/
+                       /* TODO */
                }
         }
 #endif
@@ -2179,6 +2447,8 @@ struct svgtiny_shape *svgtiny_add_shape(struct svgtiny_parse_state *state)
        shape->text = 0;
        shape->fill = state->fill;
        shape->stroke = state->stroke;
+       shape->fill_opacity = state->fill_opacity;
+       shape->stroke_opacity = state->stroke_opacity;
        shape->stroke_width = lroundf((float) state->stroke_width *
                        (state->ctm.a + state->ctm.d) / 2.0);
        if (0 < state->stroke_width && shape->stroke_width == 0)