]> gitweb.michael.orlitzky.com - libsvgtiny.git/commitdiff
Linear gradients, part 1.
authorJames Bursa <james@netsurf-browser.org>
Mon, 18 Feb 2008 20:47:03 +0000 (20:47 -0000)
committerJames Bursa <james@netsurf-browser.org>
Mon, 18 Feb 2008 20:47:03 +0000 (20:47 -0000)
svn path=/trunk/libsvgtiny/; revision=3861

colors.gperf
makefile
svgtiny.c
svgtiny.h
svgtiny_gradient.c [new file with mode: 0644]
svgtiny_internal.h [new file with mode: 0644]
svgtiny_test.c

index ae05e60a80230a40db654724bde92fc3361500c2..89152d246dcb3e9db801683d99b065c6b7484b96 100644 (file)
@@ -15,6 +15,7 @@
 %{
 #include <string.h>
 #include "svgtiny.h"
+#include "svgtiny_internal.h"
 %}
 
 struct svgtiny_named_color;
index 1c62c951e7b16fb2e23c8a8459266f3020322d9f..4273dab70fb5896bcb75d11f339de355a48564ba 100644 (file)
--- a/makefile
+++ b/makefile
@@ -5,8 +5,8 @@
 # Copyright 2008 James Bursa <james@semichrome.net>
 #
 
-SOURCE = svgtiny.c colors.c
-HDRS = svgtiny.h
+SOURCE = svgtiny.c svgtiny_gradient.c colors.c
+HDRS = svgtiny.h svgtiny_internal.h
 
 CFLAGS = -std=c99 -W -Wall -Wundef -Wpointer-arith -Wcast-qual \
        -Wcast-align -Wwrite-strings -Wstrict-prototypes \
@@ -68,7 +68,7 @@ $(OBJDIR)/%.o: %.c $(HDRS)
 
 install: $(LIBDIR)/libsvgtiny.a
        $(INSTALL) -t $(PREFIX)/lib $(LIBDIR)/libsvgtiny.a
-       $(INSTALL) -t $(PREFIX)/include $(HDRS)
+       $(INSTALL) -t $(PREFIX)/include svgtiny.h
 
 clean:
        -rm $(OBJS) $(LIBDIR)/libsvgtiny.a $(BINDIR)/svgtiny_test$(EXEEXT) colors.c
index 2847af4f84c4d8222f3dfff8e50424e52eec6738..2b99a76615b970deba23deae688f2b1891dd25ae 100644 (file)
--- a/svgtiny.c
+++ b/svgtiny.c
 #include <libxml/parser.h>
 #include <libxml/debugXML.h>
 #include "svgtiny.h"
+#include "svgtiny_internal.h"
 
 
-struct svgtiny_parse_state {
-       struct svgtiny_diagram *diagram;
-       xmlDoc *document;
-
-       float viewport_width;
-       float viewport_height;
-
-       /* current transformation matrix */
-       struct {
-               float a, b, c, d, e, f;
-       } ctm;
-
-       /*struct css_style style;*/
-
-       /* paint attributes */
-       svgtiny_colour fill;
-       svgtiny_colour stroke;
-       int stroke_width;
-};
-
-
-static bool svgtiny_parse_svg(xmlNode *svg, struct svgtiny_parse_state state);
-static bool svgtiny_parse_path(xmlNode *path, struct svgtiny_parse_state state);
-static bool svgtiny_parse_rect(xmlNode *rect, struct svgtiny_parse_state state);
-static bool svgtiny_parse_circle(xmlNode *circle,
+static svgtiny_code svgtiny_parse_svg(xmlNode *svg,
+               struct svgtiny_parse_state state);
+static svgtiny_code svgtiny_parse_path(xmlNode *path,
+               struct svgtiny_parse_state state);
+static svgtiny_code svgtiny_parse_rect(xmlNode *rect,
+               struct svgtiny_parse_state state);
+static svgtiny_code svgtiny_parse_circle(xmlNode *circle,
+               struct svgtiny_parse_state state);
+static svgtiny_code svgtiny_parse_line(xmlNode *line,
+               struct svgtiny_parse_state state);
+static svgtiny_code svgtiny_parse_poly(xmlNode *poly,
+               struct svgtiny_parse_state state, bool polygon);
+static svgtiny_code svgtiny_parse_text(xmlNode *text,
                struct svgtiny_parse_state state);
-static bool svgtiny_parse_line(xmlNode *line, struct svgtiny_parse_state state);
-static bool svgtiny_parse_poly(xmlNode *poly, struct svgtiny_parse_state state,
-               bool polygon);
-static bool svgtiny_parse_text(xmlNode *text, struct svgtiny_parse_state state);
 static void svgtiny_parse_position_attributes(const xmlNode *node,
                const struct svgtiny_parse_state state,
                float *x, float *y, float *width, float *height);
@@ -55,18 +40,18 @@ static float svgtiny_parse_length(const char *s, int viewport_size,
                const struct svgtiny_parse_state state);
 static void svgtiny_parse_paint_attributes(const xmlNode *node,
                struct svgtiny_parse_state *state);
-static void svgtiny_parse_color(const char *s, svgtiny_colour *c,
-               struct svgtiny_parse_state *state);
 static void svgtiny_parse_font_attributes(const xmlNode *node,
                struct svgtiny_parse_state *state);
 static void svgtiny_parse_transform_attributes(xmlNode *node,
                struct svgtiny_parse_state *state);
-static struct svgtiny_shape *svgtiny_add_shape(
-               struct svgtiny_parse_state *state);
-static void svgtiny_transform_path(float *p, unsigned int n,
+static svgtiny_code svgtiny_add_path(float *p, unsigned int n,
                struct svgtiny_parse_state *state);
 
 
+/**
+ * Create a new svgtiny_diagram structure.
+ */
+
 struct svgtiny_diagram *svgtiny_create(void)
 {
        struct svgtiny_diagram *diagram;
@@ -77,11 +62,17 @@ struct svgtiny_diagram *svgtiny_create(void)
 
        diagram->shape = 0;
        diagram->shape_count = 0;
+       diagram->error_line = 0;
+       diagram->error_message = 0;
 
        return diagram;
 }
 
 
+/**
+ * Parse a block of memory into a svgtiny_diagram.
+ */
+
 svgtiny_code svgtiny_parse(struct svgtiny_diagram *diagram,
                const char *buffer, size_t size, const char *url,
                int viewport_width, int viewport_height)
@@ -89,6 +80,8 @@ svgtiny_code svgtiny_parse(struct svgtiny_diagram *diagram,
        xmlDoc *document;
        xmlNode *svg;
        struct svgtiny_parse_state state;
+       float x, y, width, height;
+       svgtiny_code code;
 
        assert(diagram);
        assert(buffer);
@@ -96,8 +89,7 @@ svgtiny_code svgtiny_parse(struct svgtiny_diagram *diagram,
 
        /* parse XML to tree */
        document = xmlReadMemory(buffer, size, url, 0,
-                       XML_PARSE_NONET | XML_PARSE_COMPACT |
-                       XML_PARSE_DTDVALID /* needed for xmlGetID to work */);
+                       XML_PARSE_NONET | XML_PARSE_COMPACT);
        if (!document)
                return svgtiny_LIBXML_ERROR;
 
@@ -111,7 +103,6 @@ svgtiny_code svgtiny_parse(struct svgtiny_diagram *diagram,
                return svgtiny_NOT_SVG;
 
        /* get graphic dimensions */
-       float x, y, width, height;
        state.diagram = diagram;
        state.document = document;
        state.viewport_width = viewport_width;
@@ -120,6 +111,7 @@ svgtiny_code svgtiny_parse(struct svgtiny_diagram *diagram,
        diagram->width = width;
        diagram->height = height;
 
+       /* set up parsing state */
        state.viewport_width = width;
        state.viewport_height = height;
        state.ctm.a = 1; /*(float) viewport_width / (float) width;*/
@@ -133,12 +125,15 @@ svgtiny_code svgtiny_parse(struct svgtiny_diagram *diagram,
        state.fill = 0x000000;
        state.stroke = svgtiny_TRANSPARENT;
        state.stroke_width = 1;
+       state.linear_gradient_stop_count = 0;
 
-       svgtiny_parse_svg(svg, state);
+       /* parse tree */
+       code = svgtiny_parse_svg(svg, state);
 
+       /* free XML tree */
        xmlFreeDoc(document);
 
-       return svgtiny_OK;
+       return code;
 }
 
 
@@ -146,7 +141,8 @@ svgtiny_code svgtiny_parse(struct svgtiny_diagram *diagram,
  * Parse a <svg> or <g> element node.
  */
 
-bool svgtiny_parse_svg(xmlNode *svg, struct svgtiny_parse_state state)
+svgtiny_code svgtiny_parse_svg(xmlNode *svg,
+               struct svgtiny_parse_state state)
 {
        float x, y, width, height;
 
@@ -173,47 +169,49 @@ bool svgtiny_parse_svg(xmlNode *svg, struct svgtiny_parse_state state)
        svgtiny_parse_transform_attributes(svg, &state);
 
        for (xmlNode *child = svg->children; child; child = child->next) {
-               bool ok = true;
+               svgtiny_code code = svgtiny_OK;
 
                if (child->type == XML_ELEMENT_NODE) {
                        const char *name = (const char *) child->name;
                        if (strcmp(name, "svg") == 0)
-                               ok = svgtiny_parse_svg(child, state);
+                               code = svgtiny_parse_svg(child, state);
                        else if (strcmp(name, "g") == 0)
-                               ok = svgtiny_parse_svg(child, state);
+                               code = svgtiny_parse_svg(child, state);
                        else if (strcmp(name, "a") == 0)
-                               ok = svgtiny_parse_svg(child, state);
+                               code = svgtiny_parse_svg(child, state);
                        else if (strcmp(name, "path") == 0)
-                               ok = svgtiny_parse_path(child, state);
+                               code = svgtiny_parse_path(child, state);
                        else if (strcmp(name, "rect") == 0)
-                               ok = svgtiny_parse_rect(child, state);
+                               code = svgtiny_parse_rect(child, state);
                        else if (strcmp(name, "circle") == 0)
-                               ok = svgtiny_parse_circle(child, state);
+                               code = svgtiny_parse_circle(child, state);
                        else if (strcmp(name, "line") == 0)
-                               ok = svgtiny_parse_line(child, state);
+                               code = svgtiny_parse_line(child, state);
                        else if (strcmp(name, "polyline") == 0)
-                               ok = svgtiny_parse_poly(child, state, false);
+                               code = svgtiny_parse_poly(child, state, false);
                        else if (strcmp(name, "polygon") == 0)
-                               ok = svgtiny_parse_poly(child, state, true);
+                               code = svgtiny_parse_poly(child, state, true);
                        else if (strcmp(name, "text") == 0)
-                               ok = svgtiny_parse_text(child, state);
+                               code = svgtiny_parse_text(child, state);
                }
 
-               if (!ok)
-                       return false;
+               if (code != svgtiny_OK)
+                       return code;
        }
 
-       return true;
+       return svgtiny_OK;
 }
 
 
+
 /**
  * Parse a <path> element node.
  *
  * http://www.w3.org/TR/SVG11/paths#PathElement
  */
 
-bool svgtiny_parse_path(xmlNode *path, struct svgtiny_parse_state state)
+svgtiny_code svgtiny_parse_path(xmlNode *path,
+               struct svgtiny_parse_state state)
 {
        char *s, *path_d;
 
@@ -223,16 +221,15 @@ bool svgtiny_parse_path(xmlNode *path, struct svgtiny_parse_state state)
        /* read d attribute */
        s = path_d = (char *) xmlGetProp(path, (const xmlChar *) "d");
        if (!s) {
-               /*LOG(("path missing d attribute"));*/
-               return false;
+               state.diagram->error_line = path->line;
+               state.diagram->error_message = "path: missing d attribute";
+               return svgtiny_SVG_ERROR;
        }
 
        /* allocate space for path: it will never have more elements than d */
        float *p = malloc(sizeof p[0] * strlen(s));
-       if (!p) {
-               /*LOG(("out of memory"));*/
-               return false;
-       }
+       if (!p)
+               return svgtiny_OUT_OF_MEMORY;
 
        /* parse d and build path */
        for (unsigned int i = 0; s[i]; i++)
@@ -408,18 +405,7 @@ bool svgtiny_parse_path(xmlNode *path, struct svgtiny_parse_state state)
 
        xmlFree(path_d);
 
-       svgtiny_transform_path(p, i, &state);
-
-       struct svgtiny_shape *shape = svgtiny_add_shape(&state);
-       if (!shape) {
-               free(p);
-               return false;
-       }
-       shape->path = p;
-       shape->path_length = i;
-       state.diagram->shape_count++;
-
-       return true;
+       return svgtiny_add_path(p, i, &state);
 }
 
 
@@ -429,7 +415,8 @@ bool svgtiny_parse_path(xmlNode *path, struct svgtiny_parse_state state)
  * http://www.w3.org/TR/SVG11/shapes#RectElement
  */
 
-bool svgtiny_parse_rect(xmlNode *rect, struct svgtiny_parse_state state)
+svgtiny_code svgtiny_parse_rect(xmlNode *rect,
+               struct svgtiny_parse_state state)
 {
        float x, y, width, height;
 
@@ -440,7 +427,7 @@ bool svgtiny_parse_rect(xmlNode *rect, struct svgtiny_parse_state state)
 
        float *p = malloc(13 * sizeof p[0]);
        if (!p)
-               return false;
+               return svgtiny_OUT_OF_MEMORY;
 
        p[0] = svgtiny_PATH_MOVE;
        p[1] = x;
@@ -456,18 +443,7 @@ bool svgtiny_parse_rect(xmlNode *rect, struct svgtiny_parse_state state)
        p[11] = y + height;
        p[12] = svgtiny_PATH_CLOSE;
 
-       svgtiny_transform_path(p, 13, &state);
-
-       struct svgtiny_shape *shape = svgtiny_add_shape(&state);
-       if (!shape) {
-               free(p);
-               return false;
-       }
-       shape->path = p;
-       shape->path_length = 13;
-       state.diagram->shape_count++;
-
-       return true;
+       return svgtiny_add_path(p, 13, &state);
 }
 
 
@@ -475,7 +451,8 @@ bool svgtiny_parse_rect(xmlNode *rect, struct svgtiny_parse_state state)
  * Parse a <circle> element node.
  */
 
-bool svgtiny_parse_circle(xmlNode *circle, struct svgtiny_parse_state state)
+svgtiny_code svgtiny_parse_circle(xmlNode *circle,
+               struct svgtiny_parse_state state)
 {
        float x = 0, y = 0, r = 0;
        const float kappa = 0.5522847498;
@@ -498,7 +475,7 @@ bool svgtiny_parse_circle(xmlNode *circle, struct svgtiny_parse_state state)
 
        float *p = malloc(32 * sizeof p[0]);
        if (!p)
-               return false;
+               return svgtiny_OUT_OF_MEMORY;
 
        p[0] = svgtiny_PATH_MOVE;
        p[1] = x - r;
@@ -533,18 +510,7 @@ bool svgtiny_parse_circle(xmlNode *circle, struct svgtiny_parse_state state)
        p[30] = y;
        p[31] = svgtiny_PATH_CLOSE;
        
-       svgtiny_transform_path(p, 32, &state);
-
-       struct svgtiny_shape *shape = svgtiny_add_shape(&state);
-       if (!shape) {
-               free(p);
-               return false;
-       }
-       shape->path = p;
-       shape->path_length = 32;
-       state.diagram->shape_count++;
-
-       return true;
+       return svgtiny_add_path(p, 32, &state);
 }
 
 
@@ -552,7 +518,8 @@ bool svgtiny_parse_circle(xmlNode *circle, struct svgtiny_parse_state state)
  * Parse a <line> element node.
  */
 
-bool svgtiny_parse_line(xmlNode *line, struct svgtiny_parse_state state)
+svgtiny_code svgtiny_parse_line(xmlNode *line,
+               struct svgtiny_parse_state state)
 {
        float x1 = 0, y1 = 0, x2 = 0, y2 = 0;
 
@@ -577,7 +544,7 @@ bool svgtiny_parse_line(xmlNode *line, struct svgtiny_parse_state state)
 
        float *p = malloc(7 * sizeof p[0]);
        if (!p)
-               return false;
+               return svgtiny_OUT_OF_MEMORY;
 
        p[0] = svgtiny_PATH_MOVE;
        p[1] = x1;
@@ -587,18 +554,7 @@ bool svgtiny_parse_line(xmlNode *line, struct svgtiny_parse_state state)
        p[5] = y2;
        p[6] = svgtiny_PATH_CLOSE;
 
-       svgtiny_transform_path(p, 7, &state);
-
-       struct svgtiny_shape *shape = svgtiny_add_shape(&state);
-       if (!shape) {
-               free(p);
-               return false;
-       }
-       shape->path = p;
-       shape->path_length = 7;
-       state.diagram->shape_count++;
-
-       return true;
+       return svgtiny_add_path(p, 7, &state);
 }
 
 
@@ -609,26 +565,28 @@ bool svgtiny_parse_line(xmlNode *line, struct svgtiny_parse_state state)
  * http://www.w3.org/TR/SVG11/shapes#PolygonElement
  */
 
-bool svgtiny_parse_poly(xmlNode *poly, struct svgtiny_parse_state state,
-               bool polygon)
+svgtiny_code svgtiny_parse_poly(xmlNode *poly,
+               struct svgtiny_parse_state state, bool polygon)
 {
        char *s, *points;
 
        svgtiny_parse_paint_attributes(poly, &state);
        svgtiny_parse_transform_attributes(poly, &state);
 
-       /* read d attribute */
+       /* read points attribute */
        s = points = (char *) xmlGetProp(poly, (const xmlChar *) "points");
        if (!s) {
-               /*LOG(("poly missing d attribute"));*/
-               return false;
+               state.diagram->error_line = poly->line;
+               state.diagram->error_message =
+                               "polyline/polygon: missing points attribute";
+               return svgtiny_SVG_ERROR;
        }
 
        /* allocate space for path: it will never have more elements than s */
        float *p = malloc(sizeof p[0] * strlen(s));
        if (!p) {
-               /*LOG(("out of memory"));*/
-               return false;
+               xmlFree(points);
+               return svgtiny_OUT_OF_MEMORY;
        }
 
        /* parse s and build path */
@@ -657,18 +615,7 @@ bool svgtiny_parse_poly(xmlNode *poly, struct svgtiny_parse_state state,
 
        xmlFree(points);
 
-       svgtiny_transform_path(p, i, &state);
-
-       struct svgtiny_shape *shape = svgtiny_add_shape(&state);
-       if (!shape) {
-               free(p);
-               return false;
-       }
-       shape->path = p;
-       shape->path_length = i;
-       state.diagram->shape_count++;
-
-       return true;
+       return svgtiny_add_path(p, i, &state);
 }
 
 
@@ -676,7 +623,8 @@ bool svgtiny_parse_poly(xmlNode *poly, struct svgtiny_parse_state state,
  * Parse a <text> or <tspan> element node.
  */
 
-bool svgtiny_parse_text(xmlNode *text, struct svgtiny_parse_state state)
+svgtiny_code svgtiny_parse_text(xmlNode *text,
+               struct svgtiny_parse_state state)
 {
        float x, y, width, height;
 
@@ -694,12 +642,12 @@ bool svgtiny_parse_text(xmlNode *text, struct svgtiny_parse_state state)
        style.font_size.value.length.value *= state.ctm.a;*/
 
        for (xmlNode *child = text->children; child; child = child->next) {
-               bool ok = true;
+               svgtiny_code code = svgtiny_OK;
 
                if (child->type == XML_TEXT_NODE) {
                        struct svgtiny_shape *shape = svgtiny_add_shape(&state);
                        if (!shape)
-                               return false;
+                               return svgtiny_OUT_OF_MEMORY;
                        shape->text = strdup((const char *) child->content);
                        shape->text_x = px;
                        shape->text_y = py;
@@ -708,14 +656,14 @@ bool svgtiny_parse_text(xmlNode *text, struct svgtiny_parse_state state)
                } else if (child->type == XML_ELEMENT_NODE &&
                                strcmp((const char *) child->name,
                                        "tspan") == 0) {
-                       ok = svgtiny_parse_text(child, state);
+                       code = svgtiny_parse_text(child, state);
                }
 
-               if (!ok)
-                       return false;
+               if (!code != svgtiny_OK)
+                       return code;
        }
 
-       return true;
+       return svgtiny_OK;
 }
 
 
@@ -850,7 +798,6 @@ void svgtiny_parse_color(const char *s, svgtiny_colour *c,
        float rf, gf, bf;
        size_t len = strlen(s);
        char *id = 0, *rparen;
-       xmlAttr *id_attr;
 
        if (len == 4 && s[0] == '#') {
                if (sscanf(s + 1, "%1x%1x%1x", &r, &g, &b) == 3)
@@ -883,15 +830,16 @@ void svgtiny_parse_color(const char *s, svgtiny_colour *c,
                        rparen = strchr(id, ')');
                        if (rparen)
                                *rparen = 0;
-                       id_attr = xmlGetID(state->document,
-                                       (const xmlChar *) id);
-                       if (!id_attr) {
-                               fprintf(stderr, "id \"%s\" not found\n", id);
-                               free(id);
-                               return;
-                       }
-                       fprintf(stderr, "id \"%s\" at %p\n", id, id_attr);
+                       svgtiny_find_gradient(id, state);
                        free(id);
+                       fprintf(stderr, "linear_gradient_stop_count %i\n",
+                                       state->linear_gradient_stop_count);
+                       if (state->linear_gradient_stop_count == 0)
+                               *c = svgtiny_TRANSPARENT;
+                       else if (state->linear_gradient_stop_count == 1)
+                               *c = state->gradient_stop[0].color;
+                       else
+                               *c = svgtiny_LINEAR_GRADIENT;
                }
 
        } else {
@@ -1014,6 +962,31 @@ void svgtiny_parse_transform_attributes(xmlNode *node,
 }
 
 
+/**
+ * Add a path to the svgtiny_diagram.
+ */
+
+svgtiny_code svgtiny_add_path(float *p, unsigned int n,
+               struct svgtiny_parse_state *state)
+{
+       if (state->fill == svgtiny_LINEAR_GRADIENT)
+               return svgtiny_add_path_linear_gradient(p, n, state);
+
+       svgtiny_transform_path(p, n, state);
+
+       struct svgtiny_shape *shape = svgtiny_add_shape(state);
+       if (!shape) {
+               free(p);
+               return svgtiny_OUT_OF_MEMORY;
+       }
+       shape->path = p;
+       shape->path_length = n;
+       state->diagram->shape_count++;
+
+       return svgtiny_OK;
+}
+
+
 /**
  * Add a svgtiny_shape to the svgtiny_diagram.
  */
@@ -1033,13 +1006,17 @@ struct svgtiny_shape *svgtiny_add_shape(struct svgtiny_parse_state *state)
        shape->text = 0;
        shape->fill = state->fill;
        shape->stroke = state->stroke;
-       shape->stroke_width = state->stroke_width *
-                       (state->ctm.a + state->ctm.d) / 2;
+       shape->stroke_width = 1; /*state->stroke_width *
+                       (state->ctm.a + state->ctm.d) / 2;*/
 
        return shape;
 }
 
 
+/**
+ * Apply the current transformation matrix to a path.
+ */
+
 void svgtiny_transform_path(float *p, unsigned int n,
                struct svgtiny_parse_state *state)
 {
@@ -1074,6 +1051,10 @@ void svgtiny_transform_path(float *p, unsigned int n,
 }
 
 
+/**
+ * Free all memory used by a diagram.
+ */
+
 void svgtiny_free(struct svgtiny_diagram *svg)
 {
        assert(svg);
index 215744db8adfbd7f79152434281b242405058cff..133086c372ed50c9a2359ed1977be63cb7cc3715 100644 (file)
--- a/svgtiny.h
+++ b/svgtiny.h
@@ -14,8 +14,14 @@ typedef int svgtiny_colour;
 #define svgtiny_TRANSPARENT 0x1000000
 #ifdef riscos
 #define svgtiny_RGB(r, g, b) ((b) << 16 | (g) << 8 | (r))
+#define svgtiny_RED(c) ((c) & 0xff)
+#define svgtiny_GREEN(c) (((c) >> 8) & 0xff)
+#define svgtiny_BLUE(c) (((c) >> 16) & 0xff)
 #else
 #define svgtiny_RGB(r, g, b) ((r) << 16 | (g) << 8 | (b))
+#define svgtiny_RED(c) (((c) >> 16) & 0xff)
+#define svgtiny_GREEN(c) (((c) >> 8) & 0xff)
+#define svgtiny_BLUE(c) ((c) & 0xff)
 #endif
 
 struct svgtiny_shape {
@@ -33,6 +39,9 @@ struct svgtiny_diagram {
 
        struct svgtiny_shape *shape;
        unsigned int shape_count;
+
+       unsigned short error_line;
+       const char *error_message;
 };
 
 typedef enum {
@@ -40,6 +49,7 @@ typedef enum {
        svgtiny_OUT_OF_MEMORY,
        svgtiny_LIBXML_ERROR,
        svgtiny_NOT_SVG,
+       svgtiny_SVG_ERROR,
 } svgtiny_code;
 
 enum {
@@ -61,7 +71,4 @@ svgtiny_code svgtiny_parse(struct svgtiny_diagram *diagram,
                int width, int height);
 void svgtiny_free(struct svgtiny_diagram *svg);
 
-const struct svgtiny_named_color *
-svgtiny_color_lookup (register const char *str, register unsigned int len);
-
 #endif
diff --git a/svgtiny_gradient.c b/svgtiny_gradient.c
new file mode 100644 (file)
index 0000000..8317cea
--- /dev/null
@@ -0,0 +1,517 @@
+/*
+ * This file is part of Libsvgtiny
+ * Licensed under the MIT License,
+ *                http://opensource.org/licenses/mit-license.php
+ * Copyright 2008 James Bursa <james@semichrome.net>
+ */
+
+#define _GNU_SOURCE  /* for strndup */
+#include <assert.h>
+#include <string.h>
+#include "svgtiny.h"
+#include "svgtiny_internal.h"
+
+#define GRADIENT_DEBUG
+
+static svgtiny_code svgtiny_parse_linear_gradient(xmlNode *linear,
+               struct svgtiny_parse_state *state);
+static float svgtiny_parse_gradient_offset(const char *s);
+static void svgtiny_path_bbox(float *p, unsigned int n,
+               float *x0, float *y0, float *x1, float *y1);
+
+
+/**
+ * Find a gradient by id and parse it.
+ */
+
+void svgtiny_find_gradient(const char *id, struct svgtiny_parse_state *state)
+{
+       fprintf(stderr, "svgtiny_find_gradient: id \"%s\"\n", id);
+
+       state->linear_gradient_stop_count = 0;
+
+       xmlNode *gradient = svgtiny_find_element_by_id(
+                       (xmlNode *) state->document, id);
+       fprintf(stderr, "gradient %p\n", gradient);
+       if (!gradient) {
+               fprintf(stderr, "gradient \"%s\" not found\n", id);
+               return;
+       }
+
+       fprintf(stderr, "gradient name \"%s\"\n", gradient->name);
+       if (strcmp((const char *) gradient->name, "linearGradient") == 0) {
+               svgtiny_parse_linear_gradient(gradient, state);
+       }
+}
+
+
+/**
+ * Parse a <linearGradient> element node.
+ *
+ * http://www.w3.org/TR/SVG11/pservers#LinearGradients
+ */
+
+svgtiny_code svgtiny_parse_linear_gradient(xmlNode *linear,
+               struct svgtiny_parse_state *state)
+{
+       xmlAttr *href = xmlHasProp(linear, (const xmlChar *) "href");
+       if (href && href->children->content[0] == '#')
+               svgtiny_find_gradient((const char *) href->children->content
+                               + 1, state);
+
+       unsigned int i = 0;
+       for (xmlNode *stop = linear->children; stop; stop = stop->next) {
+               float offset = -1;
+               svgtiny_colour color = svgtiny_TRANSPARENT;
+
+               if (stop->type != XML_ELEMENT_NODE)
+                       continue;
+               if (strcmp((const char *) stop->name, "stop") != 0)
+                       continue;
+
+               for (xmlAttr *attr = stop->properties; attr;
+                               attr = attr->next) {
+                       const char *name = (const char *) attr->name;
+                       const char *content =
+                                       (const char *) attr->children->content;
+                       if (strcmp(name, "offset") == 0)
+                               offset = svgtiny_parse_gradient_offset(content);
+                       else if (strcmp(name, "stop-color") == 0)
+                               svgtiny_parse_color(content, &color, state);
+                       else if (strcmp(name, "style") == 0) {
+                               const char *s;
+                               char *value;
+                               if ((s = strstr(content, "stop-color:"))) {
+                                       s += 11;
+                                       while (*s == ' ')
+                                               s++;
+                                       value = strndup(s, strcspn(s, "; "));
+                                       svgtiny_parse_color(value, &color,
+                                                       state);
+                                       free(value);
+                               }
+                       }
+               }
+
+               if (offset != -1 && color != svgtiny_TRANSPARENT) {
+                       fprintf(stderr, "stop %g %x\n", offset, color);
+                       state->gradient_stop[i].offset = offset;
+                       state->gradient_stop[i].color = color;
+                       i++;
+               }
+
+               if (i == svgtiny_MAX_STOPS)
+                       break;
+       }
+
+       if (i)
+               state->linear_gradient_stop_count = i;
+
+       return svgtiny_OK;
+}
+
+
+float svgtiny_parse_gradient_offset(const char *s)
+{
+       int num_length = strspn(s, "0123456789+-.");
+       const char *unit = s + num_length;
+       float n = atof((const char *) s);
+
+       if (unit[0] == 0)
+               ;
+       else if (unit[0] == '%')
+               n /= 100.0;
+       else
+               return -1;
+
+       if (n < 0)
+               n = 0;
+       if (1 < n)
+               n = 1;
+       return n;
+}
+
+
+/**
+ * Add a path with a linear gradient fill to the svgtiny_diagram.
+ */
+
+svgtiny_code svgtiny_add_path_linear_gradient(float *p, unsigned int n,
+               struct svgtiny_parse_state *state)
+{
+       /* determine object bounding box */
+       float object_x0, object_y0, object_x1, object_y1;
+       svgtiny_path_bbox(p, n, &object_x0, &object_y0, &object_x1, &object_y1);
+       #ifdef GRADIENT_DEBUG
+       fprintf(stderr, "object bbox: (%g %g) (%g %g)\n",
+                       object_x0, object_y0, object_x1, object_y1);
+       #endif
+
+       /* compute gradient vector */
+       float gradient_x0 = 0, gradient_y0 = 0,
+             gradient_x1 = 1, gradient_y1 = 0.7,
+             gradient_dx, gradient_dy;
+       gradient_x0 = object_x0 + gradient_x0 * (object_x1 - object_x0);
+       gradient_y0 = object_y0 + gradient_y0 * (object_y1 - object_y0);
+       gradient_x1 = object_x0 + gradient_x1 * (object_x1 - object_x0);
+       gradient_y1 = object_y0 + gradient_y1 * (object_y1 - object_y0);
+       gradient_dx = gradient_x1 - gradient_x0;
+       gradient_dy = gradient_y1 - gradient_y0;
+       #ifdef GRADIENT_DEBUG
+       fprintf(stderr, "gradient vector: (%g %g) => (%g %g)\n",
+                       gradient_x0, gradient_y0, gradient_x1, gradient_y1);
+       #endif
+
+       /* show theoretical gradient strips for debugging */
+       /*unsigned int strips = 10;
+       for (unsigned int z = 0; z != strips; z++) {
+               float f0, fd, strip_x0, strip_y0, strip_dx, strip_dy;
+               f0 = (float) z / (float) strips;
+               fd = (float) 1 / (float) strips;
+               strip_x0 = gradient_x0 + f0 * gradient_dx;
+               strip_y0 = gradient_y0 + f0 * gradient_dy;
+               strip_dx = fd * gradient_dx;
+               strip_dy = fd * gradient_dy;
+               fprintf(stderr, "strip %i vector: (%g %g) + (%g %g)\n",
+                               z, strip_x0, strip_y0, strip_dx, strip_dy);
+
+               float *p = malloc(13 * sizeof p[0]);
+               if (!p)
+                       return svgtiny_OUT_OF_MEMORY;
+               p[0] = svgtiny_PATH_MOVE;
+               p[1] = strip_x0 + (strip_dy * 3);
+               p[2] = strip_y0 - (strip_dx * 3);
+               p[3] = svgtiny_PATH_LINE;
+               p[4] = p[1] + strip_dx;
+               p[5] = p[2] + strip_dy;
+               p[6] = svgtiny_PATH_LINE;
+               p[7] = p[4] - (strip_dy * 6);
+               p[8] = p[5] + (strip_dx * 6);
+               p[9] = svgtiny_PATH_LINE;
+               p[10] = p[7] - strip_dx;
+               p[11] = p[8] - strip_dy;
+               p[12] = svgtiny_PATH_CLOSE;
+               svgtiny_transform_path(p, 13, state);
+               struct svgtiny_shape *shape = svgtiny_add_shape(state);
+               if (!shape) {
+                       free(p);
+                       return svgtiny_OUT_OF_MEMORY;
+               }
+               shape->path = p;
+               shape->path_length = 13;
+               shape->fill = svgtiny_TRANSPARENT; 
+               shape->stroke = svgtiny_RGB(0, 0xff, 0);
+               state->diagram->shape_count++;
+       }*/
+
+       /* compute points on the path for triangle vertices */
+       unsigned int steps = 10;
+       float x0, y0, x1, y1;
+       float gradient_norm_squared = gradient_dx * gradient_dx +
+                                     gradient_dy * gradient_dy;
+       struct grad_point {
+               float x, y, r;
+       };
+       struct grad_point *pts = malloc(n * steps * sizeof pts[0]);
+       if (!pts)
+               return svgtiny_OUT_OF_MEMORY;
+       unsigned int pts_count = 0;
+       float min_r = 1000;
+       unsigned int min_pt = 0;
+       for (unsigned int j = 0; j != n; ) {
+               switch ((int) p[j]) {
+               case svgtiny_PATH_MOVE:
+                       x0 = p[j + 1];
+                       y0 = p[j + 2];
+                       j += 3;
+                       break;
+               case svgtiny_PATH_LINE:
+               case svgtiny_PATH_CLOSE:
+                       if (((int) p[j]) == svgtiny_PATH_LINE) {
+                               x1 = p[j + 1];
+                               y1 = p[j + 2];
+                               j += 3;
+                       } else {
+                               x1 = p[1];
+                               y1 = p[2];
+                               j++;
+                       }
+                       fprintf(stderr, "line: ");
+                       for (unsigned int z = 0; z != steps; z++) {
+                               float f, x, y, r;
+                               f = (float) z / (float) steps;
+                               x = x0 + f * (x1 - x0);
+                               y = y0 + f * (y1 - y0);
+                               r = ((x - gradient_x0) * gradient_dx +
+                                       (y - gradient_y0) * gradient_dy) /
+                                       gradient_norm_squared;
+                               fprintf(stderr, "(%g %g [%g]) ", x, y, r);
+                               pts[pts_count].x = x;
+                               pts[pts_count].y = y;
+                               pts[pts_count].r = r;
+                               if (r < min_r) {
+                                       min_r = r;
+                                       min_pt = pts_count;
+                               }
+                               pts_count++;
+                       }
+                       fprintf(stderr, "\n");
+                       x0 = x1;
+                       y0 = y1;
+                       break;
+               case svgtiny_PATH_BEZIER:
+                       fprintf(stderr, "bezier: ");
+                       for (unsigned int z = 0; z != steps; z++) {
+                               float t, x, y, r;
+                               t = (float) z / (float) steps;
+                               x = (1-t) * (1-t) * (1-t) * x0 +
+                                       3 * t * (1-t) * (1-t) * p[j + 1] +
+                                       3 * t * t * (1-t) * p[j + 3] +
+                                       t * t * t * p[j + 5];
+                               y = (1-t) * (1-t) * (1-t) * y0 +
+                                       3 * t * (1-t) * (1-t) * p[j + 2] +
+                                       3 * t * t * (1-t) * p[j + 4] +
+                                       t * t * t * p[j + 6];
+                               r = ((x - gradient_x0) * gradient_dx +
+                                       (y - gradient_y0) * gradient_dy) /
+                                       gradient_norm_squared;
+                               fprintf(stderr, "(%g %g [%g]) ", x, y, r);
+                               pts[pts_count].x = x;
+                               pts[pts_count].y = y;
+                               pts[pts_count].r = r;
+                               if (r < min_r) {
+                                       min_r = r;
+                                       min_pt = pts_count;
+                               }
+                               pts_count++;
+                       }
+                       fprintf(stderr, "\n");
+                       x0 = p[j + 5];
+                       y0 = p[j + 6];
+                       j += 7;
+                       break;
+               default:
+                       assert(0);
+               }
+       }
+       fprintf(stderr, "pts_count %i, min_pt %i, min_r %.3f\n",
+                       pts_count, min_pt, min_r);
+
+       unsigned int stop_count = state->linear_gradient_stop_count;
+       assert(2 <= stop_count);
+       unsigned int current_stop = 0;
+       float last_stop_r = 0;
+       float current_stop_r = state->gradient_stop[0].offset;
+       int red0, green0, blue0, red1, green1, blue1;
+       red0 = red1 = svgtiny_RED(state->gradient_stop[0].color);
+       green0 = green1 = svgtiny_GREEN(state->gradient_stop[0].color);
+       blue0 = blue1 = svgtiny_BLUE(state->gradient_stop[0].color);
+       unsigned int t, a, b;
+       t = min_pt;
+       a = (min_pt + 1) % pts_count;
+       b = min_pt == 0 ? pts_count - 1 : min_pt - 1;
+       while (a != b) {
+               float mean_r = (pts[t].r + pts[a].r + pts[b].r) / 3;
+               fprintf(stderr, "triangle: t %i %.3f a %i %.3f b %i %.3f "
+                               "mean_r %.3f\n",
+                               t, pts[t].r, a, pts[a].r, b, pts[b].r,
+                               mean_r);
+               while (current_stop != stop_count && current_stop_r < mean_r) {
+                       current_stop++;
+                       if (current_stop == stop_count)
+                               break;
+                       red0 = red1;
+                       green0 = green1;
+                       blue0 = blue1;
+                       red1 = svgtiny_RED(state->
+                                       gradient_stop[current_stop].color);
+                       green1 = svgtiny_GREEN(state->
+                                       gradient_stop[current_stop].color);
+                       blue1 = svgtiny_BLUE(state->
+                                       gradient_stop[current_stop].color);
+                       last_stop_r = current_stop_r;
+                       current_stop_r = state->
+                                       gradient_stop[current_stop].offset;
+               }
+               float *p = malloc(10 * sizeof p[0]);
+               if (!p)
+                       return svgtiny_OUT_OF_MEMORY;
+               p[0] = svgtiny_PATH_MOVE;
+               p[1] = pts[t].x;
+               p[2] = pts[t].y;
+               p[3] = svgtiny_PATH_LINE;
+               p[4] = pts[a].x;
+               p[5] = pts[a].y;
+               p[6] = svgtiny_PATH_LINE;
+               p[7] = pts[b].x;
+               p[8] = pts[b].y;
+               p[9] = svgtiny_PATH_CLOSE;
+               svgtiny_transform_path(p, 10, state);
+               struct svgtiny_shape *shape = svgtiny_add_shape(state);
+               if (!shape) {
+                       free(p);
+                       return svgtiny_OUT_OF_MEMORY;
+               }
+               shape->path = p;
+               shape->path_length = 10;
+               /*shape->fill = svgtiny_TRANSPARENT;*/
+               if (current_stop == 0)
+                       shape->fill = state->gradient_stop[0].color;
+               else if (current_stop == stop_count)
+                       shape->fill = state->
+                                       gradient_stop[stop_count - 1].color;
+               else {
+                       float stop_r = (mean_r - last_stop_r) /
+                               (current_stop_r - last_stop_r);
+                       shape->fill = svgtiny_RGB(
+                               (int) ((1 - stop_r) * red0 + stop_r * red1),
+                               (int) ((1 - stop_r) * green0 + stop_r * green1),
+                               (int) ((1 - stop_r) * blue0 + stop_r * blue1));
+               }
+               shape->stroke = svgtiny_TRANSPARENT;
+               #ifdef GRADIENT_DEBUG
+               shape->stroke = svgtiny_RGB(0, 0, 0xff);
+               #endif
+               state->diagram->shape_count++;
+               if (pts[a].r < pts[b].r) {
+                       t = a;
+                       a = (a + 1) % pts_count;
+               } else {
+                       t = b;
+                       b = b == 0 ? pts_count - 1 : b - 1;
+               }
+       }
+
+       /* render gradient vector for debugging */
+       #ifdef GRADIENT_DEBUG
+       {
+               float *p = malloc(7 * sizeof p[0]);
+               if (!p)
+                       return svgtiny_OUT_OF_MEMORY;
+               p[0] = svgtiny_PATH_MOVE;
+               p[1] = gradient_x0;
+               p[2] = gradient_y0;
+               p[3] = svgtiny_PATH_LINE;
+               p[4] = gradient_x1;
+               p[5] = gradient_y1;
+               p[6] = svgtiny_PATH_CLOSE;
+               svgtiny_transform_path(p, 7, state);
+               struct svgtiny_shape *shape = svgtiny_add_shape(state);
+               if (!shape) {
+                       free(p);
+                       return svgtiny_OUT_OF_MEMORY;
+               }
+               shape->path = p;
+               shape->path_length = 7;
+               shape->fill = svgtiny_TRANSPARENT; 
+               shape->stroke = svgtiny_RGB(0xff, 0, 0);
+               state->diagram->shape_count++;
+       }
+       #endif
+
+       /* render triangle vertices with r values for debugging */
+       #ifdef GRADIENT_DEBUG
+       for (unsigned int i = 0; i != pts_count; i++) {
+               struct svgtiny_shape *shape = svgtiny_add_shape(state);
+               if (!shape)
+                       return svgtiny_OUT_OF_MEMORY;
+               char *text = malloc(20);
+               if (!text)
+                       return svgtiny_OUT_OF_MEMORY;
+               sprintf(text, "%i=%.3f", i, pts[i].r);
+               shape->text = text;
+               shape->text_x = state->ctm.a * pts[i].x +
+                               state->ctm.c * pts[i].y + state->ctm.e;
+               shape->text_y = state->ctm.b * pts[i].x +
+                               state->ctm.d * pts[i].y + state->ctm.f;
+               shape->fill = svgtiny_RGB(0, 0, 0);
+               state->diagram->shape_count++;
+       }
+       #endif
+
+       /* plot actual path outline */
+       if (state->stroke != svgtiny_TRANSPARENT) {
+               svgtiny_transform_path(p, n, state);
+
+               struct svgtiny_shape *shape = svgtiny_add_shape(state);
+               if (!shape) {
+                       free(p);
+                       return svgtiny_OUT_OF_MEMORY;
+               }
+               shape->path = p;
+               shape->path_length = n;
+               shape->fill = svgtiny_TRANSPARENT;
+               state->diagram->shape_count++;
+       }
+
+       return svgtiny_OK;
+}
+
+
+/**
+ * Get the bounding box of path.
+ */
+
+void svgtiny_path_bbox(float *p, unsigned int n,
+               float *x0, float *y0, float *x1, float *y1)
+{
+       *x0 = *x1 = p[1];
+       *y0 = *y1 = p[2];
+
+       for (unsigned int j = 0; j != n; ) {
+               unsigned int points = 0;
+               switch ((int) p[j]) {
+               case svgtiny_PATH_MOVE:
+               case svgtiny_PATH_LINE:
+                       points = 1;
+                       break;
+               case svgtiny_PATH_CLOSE:
+                       points = 0;
+                       break;
+               case svgtiny_PATH_BEZIER:
+                       points = 3;
+                       break;
+               default:
+                       assert(0);
+               }
+               j++;
+               for (unsigned int k = 0; k != points; k++) {
+                       float x = p[j], y = p[j + 1];
+                       if (x < *x0)
+                               *x0 = x;
+                       else if (*x1 < x)
+                               *x1 = x;
+                       if (y < *y0)
+                               *y0 = y;
+                       else if (*y1 < y)
+                               *y1 = y;
+                       j += 2;
+               }
+       }
+}
+
+
+/**
+ * Find an element in the document by id.
+ */
+
+xmlNode *svgtiny_find_element_by_id(xmlNode *node, const char *id)
+{
+       xmlNode *child;
+       xmlNode *found;
+
+       for (child = node->children; child; child = child->next) {
+               if (child->type != XML_ELEMENT_NODE)
+                       continue;
+               xmlAttr *attr = xmlHasProp(child, (const xmlChar *) "id");
+               if (attr && strcmp(id, (const char *) attr->children->content)
+                               == 0)
+                       return child;
+               found = svgtiny_find_element_by_id(child, id);
+               if (found)
+                       return found;
+       }
+
+       return 0;
+}
+
diff --git a/svgtiny_internal.h b/svgtiny_internal.h
new file mode 100644 (file)
index 0000000..171f5c0
--- /dev/null
@@ -0,0 +1,62 @@
+/*
+ * This file is part of Libsvgtiny
+ * Licensed under the MIT License,
+ *                http://opensource.org/licenses/mit-license.php
+ * Copyright 2008 James Bursa <james@semichrome.net>
+ */
+
+#ifndef SVGTINY_INTERNAL_H
+#define SVGTINY_INTERNAL_H
+
+struct svgtiny_gradient_stop {
+       float offset;
+       svgtiny_colour color;
+};
+
+#define svgtiny_MAX_STOPS 10
+#define svgtiny_LINEAR_GRADIENT 0x2000000
+
+struct svgtiny_parse_state {
+       struct svgtiny_diagram *diagram;
+       xmlDoc *document;
+
+       float viewport_width;
+       float viewport_height;
+
+       /* current transformation matrix */
+       struct {
+               float a, b, c, d, e, f;
+       } ctm;
+
+       /*struct css_style style;*/
+
+       /* paint attributes */
+       svgtiny_colour fill;
+       svgtiny_colour stroke;
+       int stroke_width;
+
+       /* gradients */
+       unsigned int linear_gradient_stop_count;
+       struct svgtiny_gradient_stop gradient_stop[svgtiny_MAX_STOPS];
+};
+
+
+/* svgtiny.c */
+void svgtiny_transform_path(float *p, unsigned int n,
+               struct svgtiny_parse_state *state);
+void svgtiny_parse_color(const char *s, svgtiny_colour *c,
+               struct svgtiny_parse_state *state);
+struct svgtiny_shape *svgtiny_add_shape(struct svgtiny_parse_state *state);
+
+/* svgtiny_gradient.c */
+void svgtiny_find_gradient(const char *id, struct svgtiny_parse_state *state);
+svgtiny_code svgtiny_add_path_linear_gradient(float *p, unsigned int n,
+               struct svgtiny_parse_state *state);
+xmlNode *svgtiny_find_element_by_id(xmlNode *node, const char *id);
+
+/* colors.gperf */
+const struct svgtiny_named_color *
+               svgtiny_color_lookup(register const char *str,
+                               register unsigned int len);
+
+#endif
index 34149b9e1120df08169be255210da811811b9633..be1a4eb0c5c9581342d1f96b63f5ee360a39eb2e 100644 (file)
@@ -64,8 +64,29 @@ int main(int argc, char *argv[])
 
        /* parse */
        code = svgtiny_parse(diagram, buffer, size, argv[1], 1000, 1000);
-       if (code != svgtiny_OK)
-               fprintf(stderr, "svgtiny_parse failed: %i\n", code);
+       if (code != svgtiny_OK) {
+               fprintf(stderr, "svgtiny_parse failed: ");
+               switch (code) {
+               case svgtiny_OUT_OF_MEMORY:
+                       fprintf(stderr, "svgtiny_OUT_OF_MEMORY");
+                       break;
+               case svgtiny_LIBXML_ERROR:
+                       fprintf(stderr, "svgtiny_LIBXML_ERROR");
+                       break;
+               case svgtiny_NOT_SVG:
+                       fprintf(stderr, "svgtiny_NOT_SVG");
+                       break;
+               case svgtiny_SVG_ERROR:
+                       fprintf(stderr, "svgtiny_SVG_ERROR: line %i: %s",
+                                       diagram->error_line,
+                                       diagram->error_message);
+                       break;
+               default:
+                       fprintf(stderr, "unknown svgtiny_code %i", code);
+                       break;
+               }
+               fprintf(stderr, "\n");
+       }
 
        free(buffer);