1 /****************************************************************************
2 * RRDtool 1.3.1 Copyright by Tobi Oetiker, 1997-2008
3 ****************************************************************************
4 * rrd_gfx.c graphics wrapper for rrdtool
5 **************************************************************************/
7 /* #define DEBUG */
9 /* stupid MSVC doesnt support variadic macros = no debug for now! */
10 #ifdef _MSC_VER
11 # define RRDPRINTF()
12 #else
13 # ifdef DEBUG
14 # define RRDPRINTF(...) fprintf(stderr, __VA_ARGS__);
15 # else
16 # define RRDPRINTF(...)
17 # endif /* DEBUG */
18 #endif /* _MSC_VER */
20 #include "rrd_tool.h"
21 #include "rrd_graph.h"
24 /* create a new line */
25 void gfx_line(
26 image_desc_t *im,
27 double X0,
28 double Y0,
29 double X1,
30 double Y1,
31 double width,
32 gfx_color_t color)
33 {
34 gfx_dashed_line(im, X0, Y0, X1, Y1, width, color, 0, 0);
35 }
37 void gfx_dashed_line(
38 image_desc_t *im,
39 double X0,
40 double Y0,
41 double X1,
42 double Y1,
43 double width,
44 gfx_color_t color,
45 double dash_on,
46 double dash_off)
47 {
48 cairo_t *cr = im->cr;
49 double dashes[2];
50 double x = 0;
51 double y = 0;
53 dashes[0] = dash_on;
54 dashes[1] = dash_off;
56 cairo_save(cr);
57 cairo_new_path(cr);
58 cairo_set_line_width(cr, width);
59 gfx_line_fit(im, &x, &y);
60 gfx_line_fit(im, &X0, &Y0);
61 cairo_move_to(cr, X0, Y0);
62 gfx_line_fit(im, &X1, &Y1);
63 cairo_line_to(cr, X1, Y1);
64 if (dash_on > 0 || dash_off > 0)
65 cairo_set_dash(cr, dashes, 2, x);
66 cairo_set_source_rgba(cr, color.red, color.green, color.blue,
67 color.alpha);
68 cairo_stroke(cr);
69 cairo_restore(cr);
70 }
72 /* create a new area */
73 void gfx_new_area(
74 image_desc_t *im,
75 double X0,
76 double Y0,
77 double X1,
78 double Y1,
79 double X2,
80 double Y2,
81 gfx_color_t color)
82 {
83 cairo_t *cr = im->cr;
85 cairo_new_path(cr);
86 gfx_area_fit(im, &X0, &Y0);
87 cairo_move_to(cr, X0, Y0);
88 gfx_area_fit(im, &X1, &Y1);
89 cairo_line_to(cr, X1, Y1);
90 gfx_area_fit(im, &X2, &Y2);
91 cairo_line_to(cr, X2, Y2);
92 cairo_set_source_rgba(cr, color.red, color.green, color.blue,
93 color.alpha);
94 }
96 /* add a point to a line or to an area */
97 void gfx_add_point(
98 image_desc_t *im,
99 double x,
100 double y)
101 {
102 cairo_t *cr = im->cr;
104 gfx_area_fit(im, &x, &y);
105 cairo_line_to(cr, x, y);
106 }
108 void gfx_close_path(
109 image_desc_t *im)
110 {
111 cairo_t *cr = im->cr;
113 cairo_close_path(cr);
114 cairo_fill(cr);
115 }
117 /* create a text node */
118 static PangoLayout *gfx_prep_text(
119 image_desc_t *im,
120 double x,
121 gfx_color_t color,
122 char *font,
123 double size,
124 double tabwidth,
125 const char *text)
126 {
127 PangoLayout *layout;
128 PangoFontDescription *font_desc;
129 cairo_t *cr = im->cr;
131 /* for performance reasons we might
132 want todo that only once ... tabs will always
133 be the same */
134 long i;
135 long tab_count = strlen(text);
136 long tab_shift = fmod(x, tabwidth);
137 int border = im->text_prop[TEXT_PROP_LEGEND].size * 2.0;
139 gchar *utf8_text;
141 PangoTabArray *tab_array;
142 PangoContext *pango_context;
144 tab_array = pango_tab_array_new(tab_count, (gboolean) (1));
145 for (i = 1; i <= tab_count; i++) {
146 pango_tab_array_set_tab(tab_array,
147 i, PANGO_TAB_LEFT,
148 tabwidth * i - tab_shift + border);
149 }
150 cairo_new_path(cr);
151 cairo_set_source_rgba(cr, color.red, color.green, color.blue,
152 color.alpha);
153 layout = pango_cairo_create_layout(cr);
154 pango_context = pango_layout_get_context(layout);
155 pango_cairo_context_set_font_options(pango_context, im->font_options);
156 pango_cairo_context_set_resolution(pango_context, 100);
158 /* pango_cairo_update_context(cr, pango_context); */
160 pango_layout_set_tabs(layout, tab_array);
161 font_desc = pango_font_description_from_string(font);
162 pango_font_description_set_size(font_desc, size * PANGO_SCALE);
163 pango_layout_set_font_description(layout, font_desc);
165 /* pango expects the string to be utf-8 encoded */
166 utf8_text = g_locale_to_utf8((const gchar *) text, -1, NULL, NULL, NULL);
168 /* In case of an error, i.e. utf8_text == NULL (locale settings messed
169 * up?), we fall back to a possible "invalid UTF-8 string" warning instead
170 * of provoking a failed assertion in libpango. */
171 if (im->with_markup)
172 pango_layout_set_markup(layout, utf8_text ? utf8_text : text, -1);
173 else
174 pango_layout_set_text(layout, utf8_text ? utf8_text : text, -1);
176 g_free(utf8_text);
177 return layout;
178 }
180 /* Size Text Node */
181 double gfx_get_text_width(
182 image_desc_t *im,
183 double start,
184 char *font,
185 double size,
186 double tabwidth,
187 char *text)
188 {
189 PangoLayout *layout;
190 PangoRectangle log_rect;
191 gfx_color_t color = { 0, 0, 0, 0 };
192 layout = gfx_prep_text(im, start, color, font, size, tabwidth, text);
193 pango_layout_get_pixel_extents(layout, NULL, &log_rect);
194 pango_tab_array_free(pango_layout_get_tabs(layout));
195 g_object_unref(layout);
196 return log_rect.width;
197 }
199 void gfx_text(
200 image_desc_t *im,
201 double x,
202 double y,
203 gfx_color_t color,
204 char *font,
205 double size,
206 double tabwidth,
207 double angle,
208 enum gfx_h_align_en h_align,
209 enum gfx_v_align_en v_align,
210 const char *text)
211 {
212 PangoLayout *layout;
213 PangoRectangle log_rect;
214 PangoRectangle ink_rect;
215 cairo_t *cr = im->cr;
216 double sx = 0;
217 double sy = 0;
219 cairo_save(cr);
220 cairo_translate(cr, x, y);
221 /* gfx_line(cr,-2,0,2,0,1,color);
222 gfx_line(cr,0,-2,0,2,1,color); */
223 layout = gfx_prep_text(im, x, color, font, size, tabwidth, text);
224 pango_layout_get_pixel_extents(layout, &ink_rect, &log_rect);
225 cairo_rotate(cr, -angle * G_PI / 180.0);
226 sx = log_rect.x;
227 switch (h_align) {
228 case GFX_H_RIGHT:
229 sx -= log_rect.width;
230 break;
231 case GFX_H_CENTER:
232 sx -= log_rect.width / 2;
233 break;
234 case GFX_H_LEFT:
235 break;
236 case GFX_H_NULL:
237 break;
238 }
239 sy = log_rect.y;
240 switch (v_align) {
241 case GFX_V_TOP:
242 break;
243 case GFX_V_CENTER:
244 sy -= log_rect.height / 2;
245 break;
246 case GFX_V_BOTTOM:
247 sy -= log_rect.height;
248 break;
249 case GFX_V_NULL:
250 break;
251 }
252 pango_cairo_update_layout(cr, layout);
253 cairo_move_to(cr, sx, sy);
254 pango_cairo_show_layout(cr, layout);
255 pango_tab_array_free(pango_layout_get_tabs(layout));
256 g_object_unref(layout);
257 cairo_restore(cr);
259 }
261 /* convert color */
262 struct gfx_color_t gfx_hex_to_col(
263 long unsigned int color)
264 {
265 struct gfx_color_t gfx_color;
267 gfx_color.red = 1.0 / 255.0 * ((color & 0xff000000) >> (3 * 8));
268 gfx_color.green = 1.0 / 255.0 * ((color & 0x00ff0000) >> (2 * 8));
269 gfx_color.blue = 1.0 / 255.0 * ((color & 0x0000ff00) >> (1 * 8));
270 gfx_color.alpha = 1.0 / 255.0 * (color & 0x000000ff);
271 return gfx_color;
272 }
274 /* gridfit_lines */
276 void gfx_line_fit(
277 image_desc_t *im,
278 double *x,
279 double *y)
280 {
281 cairo_t *cr = im->cr;
282 double line_width;
283 double line_height;
285 if (!im->gridfit)
286 return;
287 cairo_user_to_device(cr, x, y);
288 line_width = cairo_get_line_width(cr);
289 line_height = line_width;
290 cairo_user_to_device_distance(cr, &line_width, &line_height);
291 line_width = line_width / 2.0 - (long) (line_width / 2.0);
292 line_height = line_height / 2.0 - (long) (line_height / 2.0);
293 *x = (double) ((long) (*x + 0.5)) - line_width;
294 *y = (double) ((long) (*y + 0.5)) + line_height;
295 cairo_device_to_user(cr, x, y);
296 }
298 /* gridfit_areas */
300 void gfx_area_fit(
301 image_desc_t *im,
302 double *x,
303 double *y)
304 {
305 cairo_t *cr = im->cr;
307 if (!im->gridfit)
308 return;
309 cairo_user_to_device(cr, x, y);
310 *x = (double) ((long) (*x + 0.5));
311 *y = (double) ((long) (*y + 0.5));
312 cairo_device_to_user(cr, x, y);
313 }