From 6f7443f938b95b5a5b4b66f5e2f8f93415d888b3 Mon Sep 17 00:00:00 2001 From: James Bursa Date: Mon, 18 Feb 2008 20:47:03 +0000 Subject: Linear gradients, part 1. svn path=/trunk/libsvgtiny/; revision=3861 --- colors.gperf | 1 + makefile | 6 +- svgtiny.c | 285 ++++++++++++++--------------- svgtiny.h | 13 +- svgtiny_gradient.c | 517 +++++++++++++++++++++++++++++++++++++++++++++++++++++ svgtiny_internal.h | 62 +++++++ svgtiny_test.c | 25 ++- 7 files changed, 749 insertions(+), 160 deletions(-) create mode 100644 svgtiny_gradient.c create mode 100644 svgtiny_internal.h diff --git a/colors.gperf b/colors.gperf index ae05e60..89152d2 100644 --- a/colors.gperf +++ b/colors.gperf @@ -15,6 +15,7 @@ %{ #include #include "svgtiny.h" +#include "svgtiny_internal.h" %} struct svgtiny_named_color; diff --git a/makefile b/makefile index 1c62c95..4273dab 100644 --- a/makefile +++ b/makefile @@ -5,8 +5,8 @@ # Copyright 2008 James Bursa # -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 diff --git a/svgtiny.c b/svgtiny.c index 2847af4..2b99a76 100644 --- a/svgtiny.c +++ b/svgtiny.c @@ -16,38 +16,23 @@ #include #include #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 or 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 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 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 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 or 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); diff --git a/svgtiny.h b/svgtiny.h index 215744d..133086c 100644 --- 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 index 0000000..8317cea --- /dev/null +++ b/svgtiny_gradient.c @@ -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 + */ + +#define _GNU_SOURCE /* for strndup */ +#include +#include +#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 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 index 0000000..171f5c0 --- /dev/null +++ b/svgtiny_internal.h @@ -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 + */ + +#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 diff --git a/svgtiny_test.c b/svgtiny_test.c index 34149b9..be1a4eb 100644 --- a/svgtiny_test.c +++ b/svgtiny_test.c @@ -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); -- cgit v1.2.3