Implement <ellipse> element. Improve error handling for <circle>.

svn path=/trunk/libsvgtiny/; revision=9706

diff --git a/src/svgtiny.c b/src/svgtiny.c
index 9f71dbe340ba4ce6ef5a29a227f61af430164f01..abc34ab3dee0a22b520c1e7997f72aebcffe793a 100644 (file)
--- a/src/svgtiny.c
+++ b/src/svgtiny.c
@@ -2,7 +2,7 @@
  * 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>
+ * Copyright 2008-2009 James Bursa <james@semichrome.net>
  */
 
 #define _GNU_SOURCE  /* for strndup */
@@ -22,6 +22,8 @@
 #define M_PI           3.14159265358979323846
 #endif
 
+#define KAPPA          0.5522847498
+
 static svgtiny_code svgtiny_parse_svg(xmlNode *svg,
                struct svgtiny_parse_state state);
 static svgtiny_code svgtiny_parse_path(xmlNode *path,
@@ -30,6 +32,8 @@ 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_ellipse(xmlNode *ellipse,
+               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,
@@ -186,6 +190,8 @@ svgtiny_code svgtiny_parse_svg(xmlNode *svg,
                                code = svgtiny_parse_rect(child, state);
                        else if (strcmp(name, "circle") == 0)
                                code = svgtiny_parse_circle(child, state);
+                       else if (strcmp(name, "ellipse") == 0)
+                               code = svgtiny_parse_ellipse(child, state);
                        else if (strcmp(name, "line") == 0)
                                code = svgtiny_parse_line(child, state);
                        else if (strcmp(name, "polyline") == 0)
@@ -480,8 +486,7 @@ svgtiny_code svgtiny_parse_rect(xmlNode *rect,
 svgtiny_code svgtiny_parse_circle(xmlNode *circle,
                struct svgtiny_parse_state state)
 {
-       float x = 0, y = 0, r = 0;
-       const float kappa = 0.5522847498;
+       float x = 0, y = 0, r = -1;
 
        for (xmlAttr *attr = circle->properties; attr; attr = attr->next) {
                const char *name = (const char *) attr->name;
@@ -499,40 +504,126 @@ svgtiny_code svgtiny_parse_circle(xmlNode *circle,
        svgtiny_parse_paint_attributes(circle, &state);
        svgtiny_parse_transform_attributes(circle, &state);
 
+       if (r < 0) {
+               state.diagram->error_line = circle->line;
+               state.diagram->error_message = "circle: r missing or negative";
+               return svgtiny_SVG_ERROR;
+       }
+       if (r == 0)
+               return svgtiny_OK;
+
        float *p = malloc(32 * sizeof p[0]);
        if (!p)
                return svgtiny_OUT_OF_MEMORY;
 
        p[0] = svgtiny_PATH_MOVE;
-       p[1] = x - r;
+       p[1] = x + r;
        p[2] = y;
        p[3] = svgtiny_PATH_BEZIER;
-       p[4] = x - r;
-       p[5] = y + r * kappa;
-       p[6] = x - r * kappa;
+       p[4] = x + r;
+       p[5] = y + r * KAPPA;
+       p[6] = x + r * KAPPA;
        p[7] = y + r;
        p[8] = x;
        p[9] = y + r;
        p[10] = svgtiny_PATH_BEZIER;
-       p[11] = x + r * kappa;
+       p[11] = x - r * KAPPA;
        p[12] = y + r;
-       p[13] = x + r;
-       p[14] = y + r * kappa;
-       p[15] = x + r;
+       p[13] = x - r;
+       p[14] = y + r * KAPPA;
+       p[15] = x - r;
        p[16] = y;
        p[17] = svgtiny_PATH_BEZIER;
-       p[18] = x + r;
-       p[19] = y - r * kappa;
-       p[20] = x + r * kappa;
+       p[18] = x - r;
+       p[19] = y - r * KAPPA;
+       p[20] = x - r * KAPPA;
        p[21] = y - r;
        p[22] = x;
        p[23] = y - r;
        p[24] = svgtiny_PATH_BEZIER;
-       p[25] = x - r * kappa;
+       p[25] = x + r * KAPPA;
        p[26] = y - r;
-       p[27] = x - r;
-       p[28] = y - r * kappa;
-       p[29] = x - r;
+       p[27] = x + r;
+       p[28] = y - r * KAPPA;
+       p[29] = x + r;
+       p[30] = y;
+       p[31] = svgtiny_PATH_CLOSE;
+       
+       return svgtiny_add_path(p, 32, &state);
+}
+
+
+/**
+ * Parse an <ellipse> element node.
+ */
+
+svgtiny_code svgtiny_parse_ellipse(xmlNode *ellipse,
+               struct svgtiny_parse_state state)
+{
+       float x = 0, y = 0, rx = -1, ry = -1;
+
+       for (xmlAttr *attr = ellipse->properties; attr; attr = attr->next) {
+               const char *name = (const char *) attr->name;
+               const char *content = (const char *) attr->children->content;
+               if (strcmp(name, "cx") == 0)
+                       x = svgtiny_parse_length(content,
+                                       state.viewport_width, state);
+               else if (strcmp(name, "cy") == 0)
+                       y = svgtiny_parse_length(content,
+                                       state.viewport_height, state);
+               else if (strcmp(name, "rx") == 0)
+                       rx = svgtiny_parse_length(content,
+                                       state.viewport_width, state);
+               else if (strcmp(name, "ry") == 0)
+                       ry = svgtiny_parse_length(content,
+                                       state.viewport_width, state);
+        }
+       svgtiny_parse_paint_attributes(ellipse, &state);
+       svgtiny_parse_transform_attributes(ellipse, &state);
+
+       if (rx < 0 || ry < 0) {
+               state.diagram->error_line = ellipse->line;
+               state.diagram->error_message = "ellipse: rx or ry missing "
+                               "or negative";
+               return svgtiny_SVG_ERROR;
+       }
+       if (rx == 0 || ry == 0)
+               return svgtiny_OK;
+
+       float *p = malloc(32 * sizeof p[0]);
+       if (!p)
+               return svgtiny_OUT_OF_MEMORY;
+
+       p[0] = svgtiny_PATH_MOVE;
+       p[1] = x + rx;
+       p[2] = y;
+       p[3] = svgtiny_PATH_BEZIER;
+       p[4] = x + rx;
+       p[5] = y + ry * KAPPA;
+       p[6] = x + rx * KAPPA;
+       p[7] = y + ry;
+       p[8] = x;
+       p[9] = y + ry;
+       p[10] = svgtiny_PATH_BEZIER;
+       p[11] = x - rx * KAPPA;
+       p[12] = y + ry;
+       p[13] = x - rx;
+       p[14] = y + ry * KAPPA;
+       p[15] = x - rx;
+       p[16] = y;
+       p[17] = svgtiny_PATH_BEZIER;
+       p[18] = x - rx;
+       p[19] = y - ry * KAPPA;
+       p[20] = x - rx * KAPPA;
+       p[21] = y - ry;
+       p[22] = x;
+       p[23] = y - ry;
+       p[24] = svgtiny_PATH_BEZIER;
+       p[25] = x + rx * KAPPA;
+       p[26] = y - ry;
+       p[27] = x + rx;
+       p[28] = y - ry * KAPPA;
+       p[29] = x + rx;
        p[30] = y;
        p[31] = svgtiny_PATH_CLOSE;