gvrender_core_pov.c

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/**********************************************************
*            Copyright (c) 2011 Andy Jeutter              *
*            AKA HallerHarry at gmx.de                    *
*            All rights reserved.                         *
**********************************************************/
 
/*************************************************************************
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors: Details at https://graphviz.org
 *************************************************************************/
 
#define _GNU_SOURCE
#include "config.h"
#include <assert.h>
#include <cgraph/agxbuf.h>
#include <cgraph/prisize_t.h>
#include <math.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <errno.h>
 
#include <common/macros.h>
#include <common/const.h>
 
#include <gvc/gvplugin_render.h>
#include <gvc/gvplugin_device.h>
#include <gvc/gvio.h>
#include <gvc/gvcint.h>
 
#define POV_VERSION \
    "#version 3.6;\n"
 
#define POV_GLOBALS \
    "global_settings { assumed_gamma 1.0 }\n"
 
#define POV_DEFAULT \
    "#default { finish { ambient 0.1 diffuse 0.9 } }\n"
 
#define POV_INCLUDE \
    "#include \"colors.inc\"\n"\
    "#include \"textures.inc\"\n"\
    "#include \"shapes.inc\"\n"
 
#define POV_LIGHT \
    "light_source { <1500,3000,-2500> color White }\n"
 
#define POV_CAMERA \
    "camera { location <%.3f , %.3f , -500.000>\n"\
    "         look_at  <%.3f , %.3f , 0.000>\n"\
    "         right x * image_width / image_height\n"\
    "         angle %.3f\n"\
    "}\n"
 
#define POV_SKY_AND_GND \
    "//sky\n"\
    "plane { <0, 1, 0>, 1 hollow\n"\
    "    texture {\n"\
    "        pigment { bozo turbulence 0.95\n"\
    "            color_map {\n"\
    "                [0.00 rgb <0.05, 0.20, 0.50>]\n"\
    "                [0.50 rgb <0.05, 0.20, 0.50>]\n"\
    "                [0.75 rgb <1.00, 1.00, 1.00>]\n"\
    "                [0.75 rgb <0.25, 0.25, 0.25>]\n"\
    "                [1.00 rgb <0.50, 0.50, 0.50>]\n"\
    "            }\n"\
    "            scale <1.00, 1.00, 1.50> * 2.50\n"\
    "            translate <0.00, 0.00, 0.00>\n"\
    "        }\n"\
    "        finish { ambient 1 diffuse 0 }\n"\
    "    }\n"\
    "    scale 10000\n"\
    "}\n"\
    "//mist\n"\
    "fog { fog_type 2\n"\
    "    distance 50\n"\
    "    color rgb <1.00, 1.00, 1.00> * 0.75\n"\
    "    fog_offset 0.10\n"\
    "    fog_alt 1.50\n"\
    "    turbulence 1.75\n"\
    "}\n"\
    "//gnd\n"\
    "plane { <0.00, 1.00, 0.00>, 0\n"\
    "    texture {\n"\
    "        pigment{ color rgb <0.25, 0.45, 0.00> }\n"\
    "        normal { bumps 0.75 scale 0.01 }\n"\
    "        finish { phong 0.10 }\n"\
    "    }\n"\
    "}\n"
 
#define POV_BOX \
    "box { <%.3f, %.3f, %.3f>, <%.3f, %.3f, %.3f>\n"
 
#define POV_SCALE1 \
    "scale %.3f\n"
 
#define POV_SCALE3 \
    "scale    "POV_VECTOR3"\n"
 
#define POV_ROTATE \
    "rotate   "POV_VECTOR3"\n"
 
#define POV_TRANSLATE \
    "translate<%9.3f, %9.3f, %d.000>\n"
 
#define END \
    "}\n"
 
#define POV_TORUS \
    "torus { %.3f, %.3f\n"
 
#define POV_SPHERE_SWEEP \
    "sphere_sweep {\n"\
    "    %s\n"\
    "    %" PRISIZE_T ",\n"
 
#define POV_SPHERE \
    "sphere {"POV_VECTOR3", 1.0\n"      // center, radius
 
#define POV_TEXT \
    "text {\n"\
    "    ttf \"%s\",\n"\
    "    \"%s\", %.3f, %.3f\n"
 
#define POV_DECLARE \
    "#declare %s = %s;\n"
 
#define POV_OBJECT \
    "object { %s }\n"
 
#define POV_VERBATIM \
    "%s\n"
 
#define POV_DEBUG \
    "#debug %s\n"
 
#define POV_POLYGON \
    "polygon { %" PRISIZE_T ",\n"
 
#define POV_VECTOR3 \
    "<%9.3f, %9.3f, %9.3f>"
 
#define POV_PIGMENT_COLOR \
    "pigment { color %s }\n"
 
#define POV_COLOR_NAME \
    "%s transmit %.3f"
 
#define POV_COLOR_RGB \
    "rgb"POV_VECTOR3" transmit %.3f"
 
//colors are taken from /usr/share/povray-3.6/include/colors.inc
//list must be LANG_C sorted (all lower case)
#define POV_COLORS \
"aquamarine",\
"bakerschoc",\
"black",\
"blue",\
"blueviolet",\
"brass",\
"brightgold",\
"bronze",\
"bronze2",\
"brown",\
"cadetblue",\
"clear",\
"coolcopper",\
"copper",\
"coral",\
"cornflowerblue",\
"cyan",\
"darkbrown",\
"darkgreen",\
"darkolivegreen",\
"darkorchid",\
"darkpurple",\
"darkslateblue",\
"darkslategray",\
"darkslategrey",\
"darktan",\
"darkturquoise",\
"darkwood",\
"dkgreencopper",\
"dustyrose",\
"feldspar",\
"firebrick",\
"flesh",\
"forestgreen",\
"gold",\
"goldenrod",\
"gray05",\
"gray10",\
"gray15",\
"gray20",\
"gray25",\
"gray30",\
"gray35",\
"gray40",\
"gray45",\
"gray50",\
"gray55",\
"gray60",\
"gray65",\
"gray70",\
"gray75",\
"gray80",\
"gray85",\
"gray90",\
"gray95",\
"green",\
"greencopper",\
"greenyellow",\
"huntersgreen",\
"indianred",\
"khaki",\
"lightblue",\
"light_purple",\
"lightsteelblue",\
"lightwood",\
"limegreen",\
"magenta",\
"mandarinorange",\
"maroon",\
"mediumaquamarine",\
"mediumblue",\
"mediumforestgreen",\
"mediumgoldenrod",\
"mediumorchid",\
"mediumseagreen",\
"mediumslateblue",\
"mediumspringgreen",\
"mediumturquoise",\
"mediumvioletred",\
"mediumwood",\
"med_purple",\
"mica",\
"midnightblue",\
"navy",\
"navyblue",\
"neonblue",\
"neonpink",\
"newmidnightblue",\
"newtan",\
"oldgold",\
"orange",\
"orangered",\
"orchid",\
"palegreen",\
"pink",\
"plum",\
"quartz",\
"red",\
"richblue",\
"salmon",\
"scarlet",\
"seagreen",\
"semiSweetChoc",\
"sienna",\
"silver",\
"skyblue",\
"slateblue",\
"spicypink",\
"springgreen",\
"steelblue",\
"summersky",\
"tan",\
"thistle",\
"turquoise",\
"verydarkbrown",\
"very_light_purple",\
"violet",\
"violetred",\
"wheat",\
"white",\
"yellow",\
"yellowgreen"
 
#define GV_OBJ_EXT(type, obj, name) \
        do { \
                char debug_str[256]; \
                gvprintf(job, POV_DECLARE, type, obj); \
                gvprintf(job, POV_OBJECT, type); \
                gvprintf(job, POV_DECLARE, "Min", "min_extent("type")"); \
                gvprintf(job, POV_DECLARE, "Max", "max_extent("type")"); \
                snprintf(debug_str, 256,  \
                        "concat(\"Dim = \" , vstr(3, Max - Min, \", \", 0, 3)," \
                        " \" "type": %s\", \"\\n\")", name); \
                gvprintf(job, POV_DEBUG, debug_str); \
        } while (0)
 
#define DPI 72.0
#define RENDERER_COLOR_TYPE RGBA_BYTE
typedef enum { FORMAT_POV, } format_type;
 
//#define DEBUG
 
//TODO: check why this dot file does not work (90 rotated)
//   /usr/share/graphviz/graphs/directed/NaN.gv
//TODO: add Texttures
//TODO: check how we can receive attributes from dot file
//   if we can't receive attributes set defaults in pov include file
//   - put #include "graph-scheme-fancy.inc" in pov file
//   - run povray with +L`pwd`
//   - put e.g. #declare mycolor = Gold; in graph-scheme-fancy.inc
//   - use textures and color: pigment { color mycolor transmit 0.000 }
//TODO: idea, put the whole graph in a declare= and then
//   print it with something along the line:
//   object{ graph translate{page->translation, ...} rotate{page->rotation, ...} }
 
static char *pov_knowncolors[] = { POV_COLORS };
 
static int layerz = 0;
static int z = 0;
 
static char *pov_color_as_str(GVJ_t * job, gvcolor_t color, float transparency)
{
        agxbuf c = {0};
        switch (color.type) {
        case COLOR_STRING:
#ifdef DEBUG
                gvprintf(job, "// type = %d, color = %s\n", color.type, color.u.string);
#else
                (void)job;
#endif
                if (!strcmp(color.u.string, "red"))
                        agxbprint(&c, POV_COLOR_NAME, "Red", transparency);
                else if (!strcmp(color.u.string, "green"))
                        agxbprint(&c, POV_COLOR_NAME, "Green", transparency);
                else if (!strcmp(color.u.string, "blue"))
                        agxbprint(&c, POV_COLOR_NAME, "Blue", transparency);
                else
                        agxbprint(&c, POV_COLOR_NAME, color.u.string, transparency);
                break;
        case RENDERER_COLOR_TYPE:
#ifdef DEBUG
                gvprintf(job, "// type = %d, color = %d, %d, %d\n",
                         color.type, color.u.rgba[0], color.u.rgba[1],
                         color.u.rgba[2]);
#endif
                agxbprint(&c, POV_COLOR_RGB,
                       color.u.rgba[0] / 256.0, color.u.rgba[1] / 256.0,
                       color.u.rgba[2] / 256.0, transparency);
                break;
        default:
                fprintf(stderr,
                        "oops, internal error: unhandled color type=%d %s\n",
                        color.type, color.u.string);
                assert(0);      //oops, wrong type set in gvrender_features_t?
        }
        agxbuf pov = {0};
        agxbprint(&pov, POV_PIGMENT_COLOR, agxbuse(&c));
        agxbfree(&c);
        return agxbdisown(&pov);
}
 
static void pov_comment(GVJ_t * job, char *str)
{
        gvprintf(job, "//*** comment: %s\n", str);
}
 
static void pov_begin_job(GVJ_t * job)
{
        gvputs(job, POV_VERSION);
        gvputs(job, POV_GLOBALS);
        gvputs(job, POV_DEFAULT);
        gvputs(job, POV_INCLUDE);
        gvprintf(job, POV_DECLARE, "black", "Black");
        gvprintf(job, POV_DECLARE, "white", "White");
}
 
static void pov_begin_graph(GVJ_t * job)
{
        gvprintf(job, "//*** begin_graph %s\n", agnameof(job->obj->u.g));
#ifdef DEBUG
        gvprintf(job, "// graph_index = %d, pages = %d, layer = %d/%d\n",
                 job->graph_index, job->numPages, job->layerNum,
                 job->numLayers);
        gvprintf(job, "// pagesArraySize.x,y = %d,%d\n", job->pagesArraySize.x,
                 job->pagesArraySize.y);
        gvprintf(job, "// pagesArrayFirst.x,y = %d,%d\n",
                 job->pagesArrayFirst.x, job->pagesArrayFirst.y);
        gvprintf(job, "// pagesArrayElem.x,y = %d,%d\n", job->pagesArrayElem.x,
                 job->pagesArrayElem.y);
        gvprintf(job, "// bb.LL,UR = %.3f,%.3f, %.3f,%.3f\n", job->bb.LL.x,
                 job->bb.LL.y, job->bb.UR.x, job->bb.UR.y);
        gvprintf(job, "// pageBox in graph LL,UR = %.3f,%.3f, %.3f,%.3f\n",
                 job->pageBox.LL.x, job->pageBox.LL.y, job->pageBox.UR.x,
                 job->pageBox.UR.y);
        gvprintf(job, "// pageSize.x,y = %.3f,%.3f\n", job->pageSize.x,
                 job->pageSize.y);
        gvprintf(job, "// focus.x,y = %.3f,%.3f\n", job->focus.x, job->focus.y);
        gvprintf(job, "// zoom = %.3f, rotation = %d\n", job->zoom,
                 (float)job->rotation);
        gvprintf(job, "// view port.x,y = %.3f,%.3f\n", job->view.x,
                 job->view.y);
        gvprintf(job, "// canvasBox LL,UR = %.3f,%.3f, %.3f,%.3f\n",
                 job->canvasBox.LL.x, job->canvasBox.LL.y, job->canvasBox.UR.x,
                 job->canvasBox.UR.y);
        gvprintf(job, "// pageBoundingBox LL,UR = %d,%d, %d,%d\n",
                 job->pageBoundingBox.LL.x, job->pageBoundingBox.LL.y,
                 job->pageBoundingBox.UR.x, job->pageBoundingBox.UR.y);
        gvprintf(job, "// boundingBox (all pages) LL,UR = %d,%d, %d,%d\n",
                 job->boundingBox.LL.x, job->boundingBox.LL.y,
                 job->boundingBox.UR.x, job->boundingBox.UR.y);
        gvprintf(job, "// scale.x,y = %.3f,%.3f\n", job->scale.x, job->scale.y);
        gvprintf(job, "// translation.x,y = %.3f,%.3f\n", job->translation.x,
                 job->translation.y);
        gvprintf(job, "// devscale.x,y = %.3f,%.3f\n", job->devscale.x,
                 job->devscale.y);
        gvprintf(job, "// verbose = %d\n", job->common->verbose);
        gvprintf(job, "// cmd = %s\n", job->common->cmdname);
        gvprintf(job, "// info = %s, %s, %s\n", job->common->info[0],
                 job->common->info[1], job->common->info[2]);
#endif
 
        //setup scene
        double x = job->view.x / 2.0 * job->scale.x;
        double y = job->view.y / 2.0 * job->scale.y;
        double d = 500;
        double px = atan(x / d) * 180.0 / M_PI * 2.0;
        double py = atan(y / d) * 180.0 / M_PI * 2.0;
        gvprintf(job, POV_CAMERA, x, y, x, y, fmax(px, py) * 1.2);
        gvputs(job, POV_SKY_AND_GND);
        gvputs(job, POV_LIGHT);
}
 
static void pov_end_graph(GVJ_t * job)
{
        gvputs(job, "//*** end_graph\n");
}
 
static void pov_begin_layer(GVJ_t * job, char *layername, int layerNum, int numLayers)
{
        gvprintf(job, "//*** begin_layer: %s, %d/%d\n", layername, layerNum,
                 numLayers);
        layerz = layerNum * -10;
}
 
static void pov_end_layer(GVJ_t * job)
{
        gvputs(job, "//*** end_layer\n");
}
 
static void pov_begin_page(GVJ_t * job)
{
        gvputs(job, "//*** begin_page\n");
}
 
static void pov_end_page(GVJ_t * job)
{
        gvputs(job, "//*** end_page\n");
}
 
static void pov_begin_cluster(GVJ_t * job)
{
        gvputs(job, "//*** begin_cluster\n");
        layerz -= 2;
}
 
static void pov_end_cluster(GVJ_t * job)
{
        gvputs(job, "//*** end_cluster\n");
}
 
static void pov_begin_node(GVJ_t * job)
{
        gvprintf(job, "//*** begin_node: %s\n", agnameof(job->obj->u.n));
}
 
static void pov_end_node(GVJ_t * job)
{
        gvputs(job, "//*** end_node\n");
}
 
static void pov_begin_edge(GVJ_t * job)
{
        gvputs(job, "//*** begin_edge\n");
        layerz -= 5;
#ifdef DEBUG
        gvprintf(job, "// layerz = %d.000\n", layerz);
#endif
}
 
static void pov_end_edge(GVJ_t * job)
{
        gvputs(job, "//*** end_edge\n");
        layerz += 5;
#ifdef DEBUG
        gvprintf(job, "// layerz = %d.000\n", layerz);
#endif
}
 
static void pov_textspan(GVJ_t * job, pointf c, textspan_t * span)
{
        gvprintf(job, "//*** textspan: %s, fontsize = %.3f, fontname = %s\n",
                 span->str, span->font->size, span->font->name);
        z = layerz - 9;
 
#ifdef DEBUG
        if (span->font->postscript_alias)
                gvputs(job, "// Warning: postscript_alias not handled!\n");
#endif
 
        //handle text justification
        switch (span->just) {
        case 'l':               //left justified
                break;
        case 'r':               //right justified
                c.x = c.x - span->size.x;
                break;
        default:
        case 'n':               //centered
                c.x = c.x - span->size.x / 2.0;
                break;
        }
 
        double x = (c.x + job->translation.x) * job->scale.x;
        double y = (c.y + job->translation.y) * job->scale.y;
 
        char *p = pov_color_as_str(job, job->obj->pencolor, 0.0);
 
        //pov bundled fonts: timrom.ttf, cyrvetic.ttf
        agxbuf pov = {0};
        agxbprint(&pov, POV_TEXT "        no_shadow\n",
                span->font->name, span->str, 0.25, 0.0); // font, text, depth (0.5 ... 2.0), offset
        agxbprint(&pov, "    " POV_SCALE1, span->font->size * job->scale.x);
        agxbprint(&pov, "    " POV_ROTATE, 0.0, 0.0, (float)job->rotation);
        agxbprint(&pov, "    " POV_TRANSLATE, x, y, z);
        agxbprint(&pov, "    %s" END, p);
 
#ifdef DEBUG
        GV_OBJ_EXT("Text", agxbuse(&pov), span->str);
        gvprintf(job, "sphere{<0, 0, 0>, 2\ntranslate<%f, %f, %d>\n"
                 "pigment{color Red}\nno_shadow\n}\n", x, y, z - 1);
#else
        gvputs(job, agxbuse(&pov));
#endif
 
        agxbfree(&pov);
        free(p);
}
 
static void pov_ellipse(GVJ_t * job, pointf * A, int filled)
{
        gvputs(job, "//*** ellipse\n");
        z = layerz - 6;
 
        // A[0] center, A[1] corner of ellipse
        float cx = (A[0].x + job->translation.x) * job->scale.x;
        float cy = (A[0].y + job->translation.y) * job->scale.y;
        float rx = (A[1].x - A[0].x) * job->scale.x;
        float ry = (A[1].y - A[0].y) * job->scale.y;
        float w = job->obj->penwidth / (rx + ry) / 2.0 * 5;
 
        //draw rim (torus)
        char *p = pov_color_as_str(job, job->obj->pencolor, 0.0);
 
        agxbuf pov = {0};
        agxbprint(&pov, POV_TORUS, 1.0, w); // radius, size of ring
        agxbprint(&pov, "    " POV_SCALE3, rx, (rx + ry) / 4.0, ry);
        agxbprint(&pov, "    " POV_ROTATE, 90.0, 0.0, (float)job->rotation);
        agxbprint(&pov, "    " POV_TRANSLATE, cx, cy, z);
        agxbprint(&pov, "    %s" END, p);
 
#ifdef DEBUG
        GV_OBJ_EXT("Torus", agxbuse(&pov), "");
        gvprintf(job, "sphere{<0, 0, 0>, 2\ntranslate<%f, %f, %d>\n"
                 "pigment{color Green}\nno_shadow\n}\n", cx, cy, z - 1);
#else
        gvputs(job, agxbuse(&pov));
#endif
 
        free(p);
 
        //backgroud of ellipse if filled
        if (filled) {
                p = pov_color_as_str(job, job->obj->fillcolor, 0.0);
 
                gvprintf(job, POV_SPHERE, 0.0, 0.0, 0.0);
                gvprintf(job, "    " POV_SCALE3, rx, ry, 1.0);
                gvprintf(job, "    " POV_ROTATE, 0.0, 0.0, (float)job->rotation);
                gvprintf(job, "    " POV_TRANSLATE, cx, cy, z);
                gvprintf(job, "    %s" END, p);
 
                free(p);
        }
        agxbfree(&pov);
}
 
static void pov_bezier(GVJ_t *job, pointf *A, size_t n, int filled) {
        (void)filled;
 
        gvputs(job, "//*** bezier\n");
        z = layerz - 4;
 
        char *p = pov_color_as_str(job, job->obj->fillcolor, 0.0);
 
        agxbuf pov = {0};
        agxbprint(&pov, POV_SPHERE_SWEEP, "b_spline", n + 2);
 
        for (size_t i = 0; i < n; i++) {
                agxbprint(&pov, "    " POV_VECTOR3 ", %.3f\n", A[i].x + job->translation.x,
                          A[i].y + job->translation.y, 0.0, job->obj->penwidth); // z coordinate, thickness
 
                //TODO: we currently just use the start and end points of the curve as
                //control points but we should use center of nodes
                if (i == 0 || i + 1 == n) {
                        agxbprint(&pov, "    " POV_VECTOR3 ", %.3f\n", A[i].x + job->translation.x,
                                  A[i].y + job->translation.y, 0.0, job->obj->penwidth); // z coordinate, thickness
                }
#ifdef DEBUG
                gvprintf(job, "sphere{<0, 0, 0>, 2\ntranslate<%f, %f, %d>\n"
                         "pigment{color Yellow}\nno_shadow\n}\n",
                         (A[i].x + job->translation.x) * job->scale.x,
                         (A[i].y + job->translation.y) * job->scale.y, z - 2);
#endif
        }
        // catenate pov & end str
        gvprintf(job, "%s        tolerance 0.01\n", agxbuse(&pov));
        gvprintf(job, "    " POV_SCALE3, job->scale.x, job->scale.y, 1.0);
        gvprintf(job, "    " POV_ROTATE, 0.0, 0.0, (float)job->rotation);
        gvprintf(job, "    " POV_TRANSLATE, 0.0, 0.0, z - 2);
        gvprintf(job, "    %s" END, p);
 
        free(p);
        agxbfree(&pov);
}
 
static void pov_polygon(GVJ_t *job, pointf *A, size_t n, int filled) {
        gvputs(job, "//*** polygon\n");
        z = layerz - 2;
 
        char *p = pov_color_as_str(job, job->obj->pencolor, 0.0);
 
        gvprintf(job, POV_SPHERE_SWEEP, "linear_spline", n + 1);
 
        for (size_t i = 0; i < n; i++) {
                gvprintf(job, "    " POV_VECTOR3 ", %.3f\n", A[i].x + job->translation.x,
                          A[i].y + job->translation.y, 0.0, job->obj->penwidth); // z coordinate, thickness
        }
 
        //close polygon, add starting point as final point^
        gvprintf(job, "    " POV_VECTOR3 ", %.3f\n", A[0].x + job->translation.x,
                  A[0].y + job->translation.y, 0.0, job->obj->penwidth); // z coordinate, thickness
 
        gvputs(job, "    tolerance 0.1\n");
        gvprintf(job, "    " POV_SCALE3, job->scale.x, job->scale.y, 1.0);
        gvprintf(job, "    " POV_ROTATE, 0.0, 0.0, (float)job->rotation);
        gvprintf(job, "    " POV_TRANSLATE, 0.0, 0.0, z - 2);
        gvprintf(job, "    %s" END, p);
 
        free(p);
 
        //create fill background
        if (filled) {
                p = pov_color_as_str(job, job->obj->fillcolor, 0.25);
 
                gvprintf(job, POV_POLYGON, n);
 
                for (size_t i = 0; i < n; i++) {
                        //create on z = 0 plane, then translate to real z pos
                        gvprintf(job, "\n    " POV_VECTOR3,
                               A[i].x + job->translation.x,
                               A[i].y + job->translation.y, 0.0);
                }
                gvputs(job, "\n    ");
                gvprintf(job, "    " POV_SCALE3, job->scale.x, job->scale.y, 1.0);
                gvprintf(job, "    " POV_ROTATE, 0.0, 0.0, (float)job->rotation);
                gvprintf(job, "    " POV_TRANSLATE, 0.0, 0.0, z - 2);
                gvprintf(job, "    %s" END, p);
 
                free(p);
        }
}
 
static void pov_polyline(GVJ_t *job, pointf *A, size_t n) {
        gvputs(job, "//*** polyline\n");
        z = layerz - 6;
 
        char *p = pov_color_as_str(job, job->obj->pencolor, 0.0);
 
        gvprintf(job, POV_SPHERE_SWEEP, "linear_spline", n);
 
        for (size_t i = 0; i < n; i++) {
                gvprintf(job, "    " POV_VECTOR3 ", %.3f\n", A[i].x + job->translation.x,
                          A[i].y + job->translation.y, 0.0, job->obj->penwidth); // z coordinate, thickness
        }
 
        gvputs(job, "    tolerance 0.01\n");
        gvprintf(job, "    " POV_SCALE3, job->scale.x, job->scale.y, 1.0);
        gvprintf(job, "    " POV_ROTATE, 0.0, 0.0, (float)job->rotation);
        gvprintf(job, "    " POV_TRANSLATE, 0.0, 0.0, z);
        gvprintf(job, "    %s" END, p);
 
        free(p);
}
 
gvrender_engine_t pov_engine = {
        pov_begin_job,
        0,                      /* pov_end_job */
        pov_begin_graph,
        pov_end_graph,
        pov_begin_layer,
        pov_end_layer,
        pov_begin_page,
        pov_end_page,
        pov_begin_cluster,
        pov_end_cluster,
        0,                      /* pov_begin_nodes */
        0,                      /* pov_end_nodes */
        0,                      /* pov_begin_edges */
        0,                      /* pov_end_edges */
        pov_begin_node,
        pov_end_node,
        pov_begin_edge,
        pov_end_edge,
        0,                      /* pov_begin_anchor */
        0,                      /* pov_end_anchor */
        0,                      /* pov_begin_label */
        0,                      /* pov_end_label */
        pov_textspan,
        0,                      /* pov_resolve_color */
        pov_ellipse,
        pov_polygon,
        pov_bezier,
        pov_polyline,
        pov_comment,
        0,                      /* pov_library_shape */
};
 
gvrender_features_t render_features_pov = {
        /* flags */
        GVDEVICE_DOES_LAYERS
            | GVRENDER_DOES_MAP_RECTANGLE
            | GVRENDER_DOES_MAP_CIRCLE
            | GVRENDER_DOES_MAP_POLYGON
            | GVRENDER_DOES_MAP_ELLIPSE
            | GVRENDER_DOES_MAP_BSPLINE
            | GVRENDER_NO_WHITE_BG
            | GVRENDER_DOES_TRANSFORM
            | GVRENDER_DOES_Z | GVRENDER_DOES_MAP_BSPLINE,
        4.0,                    /* default pad - graph units */
        pov_knowncolors,        /* knowncolors */
        sizeof(pov_knowncolors) / sizeof(char *),       /* strings in knowncolors */
        RENDERER_COLOR_TYPE     /* set renderer color type */
};
 
gvdevice_features_t device_features_pov = {
        GVDEVICE_DOES_TRUECOLOR,        /* flags */
        {0.0, 0.0},             /* default margin - points */
        {0.0, 0.0},             /* default page width, height - points */
        {DPI, DPI},             /* default dpi */
};
 
gvplugin_installed_t gvrender_pov_types[] = {
        {FORMAT_POV, "pov", 1, &pov_engine, &render_features_pov},
        {0, NULL, 0, NULL, NULL}
};
 
gvplugin_installed_t gvdevice_pov_types[] = {
        {FORMAT_POV, "pov:pov", 1, NULL, &device_features_pov},
        {0, NULL, 0, NULL, NULL}
};