plotters.c

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/*
 * Copyright 2004 James Bursa <bursa@users.sourceforge.net>
 *
 * This file is part of NetSurf, http://www.netsurf-browser.org/
 *
 * NetSurf is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License.
 *
 * NetSurf is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
/**
 * \file
 * RISC OS screen plotter implementation.
 */
 
#include <stdbool.h>
#include <math.h>
#include "oslib/colourtrans.h"
#include "oslib/draw.h"
#include "oslib/os.h"
 
#include "utils/log.h"
#include "netsurf/plotters.h"
 
#include "riscos/bitmap.h"
#include "riscos/image.h"
#include "riscos/gui.h"
#include "riscos/font.h"
#include "riscos/oslib_pre7.h"
 
 
int ro_plot_origin_x = 0;
int ro_plot_origin_y = 0;
struct rect ro_plot_clip_rect;
 
/** One version of the A9home OS is incapable of drawing patterned lines */
bool ro_plot_patterned_lines = true;
 
/**
 * plot a path on RISC OS
 */
static nserror
ro_plot_draw_path(const draw_path * const path,
                  int width,
                  colour c,
                  bool dotted,
                  bool dashed)
{
        static const draw_line_style line_style = {
                draw_JOIN_MITRED,
                draw_CAP_BUTT,
                draw_CAP_BUTT,
                0, 0x7fffffff,
                0, 0, 0, 0
        };
        draw_dash_pattern dash = { 0, 1, { 512 } };
        const draw_dash_pattern *dash_pattern = 0;
        os_error *error;
 
        if (width < 1)
                width = 1;
 
        if (ro_plot_patterned_lines) {
                if (dotted) {
                        dash.elements[0] = 512 * width;
                        dash_pattern = &dash;
                } else if (dashed) {
                        dash.elements[0] = 1536 * width;
                        dash_pattern = &dash;
                }
        }
 
        error = xcolourtrans_set_gcol(c << 8, 0, os_ACTION_OVERWRITE, 0, 0);
        if (error) {
                NSLOG(netsurf, INFO, "xcolourtrans_set_gcol: 0x%x: %s",
                      error->errnum, error->errmess);
                return NSERROR_INVALID;
        }
 
        error = xdraw_stroke(path, 0, 0, 0, width * 2 * 256,
                        &line_style, dash_pattern);
        if (error) {
                NSLOG(netsurf, INFO, "xdraw_stroke: 0x%x: %s", error->errnum,
                      error->errmess);
                return NSERROR_INVALID;
        }
 
        return NSERROR_OK;
}
 
 
/**
 * \brief Sets a clip rectangle for subsequent plot operations.
 *
 * \param ctx The current redraw context.
 * \param clip The rectangle to limit all subsequent plot
 *              operations within.
 * \return NSERROR_OK on success else error code.
 */
static nserror
ro_plot_clip(const struct redraw_context *ctx, const struct rect *clip)
{
        os_error *error;
        char buf[12];
 
        int clip_x0 = clip->x0 * 2;
        int clip_y0 = clip->y1 * 2;
        int clip_x1 = clip->x1 * 2;
        int clip_y1 = clip->y0 * 2;
 
        /* Avoid artefacts due to clip rectangle offsetting in EX0 EY0 modes.
         * The area the WIMP asked us to draw might have dimensions that are
         * not a multiple of 2. */
        if (clip_x0 < ro_plot_clip_rect.x0) clip_x0 = ro_plot_clip_rect.x0;
        if (clip_x1 > ro_plot_clip_rect.x1) clip_x1 = ro_plot_clip_rect.x1;
        if (clip_y0 > ro_plot_clip_rect.y0) clip_y0 = ro_plot_clip_rect.y0;
        if (clip_y1 < ro_plot_clip_rect.y1) clip_y1 = ro_plot_clip_rect.y1;
 
        clip_x0 = ro_plot_origin_x + clip_x0;
        clip_y0 = ro_plot_origin_y - clip_y0;
        clip_x1 = ro_plot_origin_x + clip_x1 - 1;
        clip_y1 = ro_plot_origin_y - clip_y1 - 1;
 
        if (clip_x1 < clip_x0 || clip_y1 < clip_y0) {
                NSLOG(netsurf, INFO, "bad clip rectangle %i %i %i %i",
                      clip_x0, clip_y0, clip_x1, clip_y1);
                return NSERROR_BAD_SIZE;
        }
 
        buf[0] = os_VDU_SET_GRAPHICS_WINDOW;
        buf[1] = clip_x0;
        buf[2] = clip_x0 >> 8;
        buf[3] = clip_y0;
        buf[4] = clip_y0 >> 8;
        buf[5] = clip_x1;
        buf[6] = clip_x1 >> 8;
        buf[7] = clip_y1;
        buf[8] = clip_y1 >> 8;
 
        error = xos_writen(buf, 9);
        if (error) {
                NSLOG(netsurf, INFO, "xos_writen: 0x%x: %s", error->errnum,
                      error->errmess);
                return NSERROR_INVALID;
        }
 
        return NSERROR_OK;
}
 
 
/**
 * Plots an arc
 *
 * plot an arc segment around (x,y), anticlockwise from angle1
 *  to angle2. Angles are measured anticlockwise from
 *  horizontal, in degrees.
 *
 * \param ctx The current redraw context.
 * \param style Style controlling the arc plot.
 * \param x The x coordinate of the arc.
 * \param y The y coordinate of the arc.
 * \param radius The radius of the arc.
 * \param angle1 The start angle of the arc.
 * \param angle2 The finish angle of the arc.
 * \return NSERROR_OK on success else error code.
 */
static nserror
ro_plot_arc(const struct redraw_context *ctx,
               const plot_style_t *style,
               int x, int y, int radius, int angle1, int angle2)
{
        os_error *error;
        int sx, sy, ex, ey;
        double t;
 
        x = ro_plot_origin_x + x * 2;
        y = ro_plot_origin_y - y * 2;
        radius <<= 1;
 
        error = xcolourtrans_set_gcol(style->fill_colour << 8, 0,
                        os_ACTION_OVERWRITE, 0, 0);
 
        if (error) {
                NSLOG(netsurf, INFO, "xcolourtrans_set_gcol: 0x%x: %s",
                      error->errnum, error->errmess);
                return NSERROR_INVALID;
        }
 
        t = ((double)angle1 * M_PI) / 180.0;
        sx = (x + (int)(radius * cos(t)));
        sy = (y + (int)(radius * sin(t)));
 
        t = ((double)angle2 * M_PI) / 180.0;
        ex = (x + (int)(radius * cos(t)));
        ey = (y + (int)(radius * sin(t)));
 
        error = xos_plot(os_MOVE_TO, x, y);     /* move to centre */
        if (error) {
                NSLOG(netsurf, INFO, "xos_plot: 0x%x: %s", error->errnum,
                      error->errmess);
                return NSERROR_INVALID;
        }
 
        error = xos_plot(os_MOVE_TO, sx, sy);   /* move to start */
        if (error) {
                NSLOG(netsurf, INFO, "xos_plot: 0x%x: %s", error->errnum,
                      error->errmess);
                return NSERROR_INVALID;
        }
 
        error = xos_plot(os_PLOT_ARC | os_PLOT_TO, ex, ey);     /* arc to end */
        if (error) {
                NSLOG(netsurf, INFO, "xos_plot: 0x%x: %s", error->errnum,
                      error->errmess);
                return NSERROR_INVALID;
        }
 
        return NSERROR_OK;
}
 
 
/**
 * Plots a circle
 *
 * Plot a circle centered on (x,y), which is optionally filled.
 *
 * \param ctx The current redraw context.
 * \param style Style controlling the circle plot.
 * \param x The x coordinate of the circle.
 * \param y The y coordinate of the circle.
 * \param radius The radius of the circle.
 * \return NSERROR_OK on success else error code.
 */
static nserror
ro_plot_disc(const struct redraw_context *ctx,
                const plot_style_t *style,
                int x, int y, int radius)
{
        os_error *error;
        if (style->fill_type != PLOT_OP_TYPE_NONE) {
                error = xcolourtrans_set_gcol(style->fill_colour << 8, 0,
                                              os_ACTION_OVERWRITE, 0, 0);
                if (error) {
                        NSLOG(netsurf, INFO,
                              "xcolourtrans_set_gcol: 0x%x: %s",
                              error->errnum,
                              error->errmess);
                        return NSERROR_INVALID;
                }
                error = xos_plot(os_MOVE_TO,
                                 ro_plot_origin_x + x * 2,
                                 ro_plot_origin_y - y * 2);
                if (error) {
                        NSLOG(netsurf, INFO, "xos_plot: 0x%x: %s",
                              error->errnum, error->errmess);
                        return NSERROR_INVALID;
                }
                error = xos_plot(os_PLOT_CIRCLE | os_PLOT_BY, radius * 2, 0);
                if (error) {
                        NSLOG(netsurf, INFO, "xos_plot: 0x%x: %s",
                              error->errnum, error->errmess);
                        return NSERROR_INVALID;
                }
        }
 
        if (style->stroke_type != PLOT_OP_TYPE_NONE) {
 
                error = xcolourtrans_set_gcol(style->stroke_colour << 8, 0,
                                              os_ACTION_OVERWRITE, 0, 0);
                if (error) {
                        NSLOG(netsurf, INFO,
                              "xcolourtrans_set_gcol: 0x%x: %s",
                              error->errnum,
                              error->errmess);
                        return NSERROR_INVALID;
                }
                error = xos_plot(os_MOVE_TO,
                                 ro_plot_origin_x + x * 2,
                                 ro_plot_origin_y - y * 2);
                if (error) {
                        NSLOG(netsurf, INFO, "xos_plot: 0x%x: %s",
                              error->errnum, error->errmess);
                        return NSERROR_INVALID;
                }
                error = xos_plot(os_PLOT_CIRCLE_OUTLINE | os_PLOT_BY,
                                 radius * 2, 0);
 
                if (error) {
                        NSLOG(netsurf, INFO, "xos_plot: 0x%x: %s",
                              error->errnum, error->errmess);
                        return NSERROR_INVALID;
                }
        }
        return NSERROR_OK;
}
 
 
/**
 * Plots a line
 *
 * plot a line from (x0,y0) to (x1,y1). Coordinates are at
 *  centre of line width/thickness.
 *
 * \param ctx The current redraw context.
 * \param style Style controlling the line plot.
 * \param line A rectangle defining the line to be drawn
 * \return NSERROR_OK on success else error code.
 */
static nserror
ro_plot_line(const struct redraw_context *ctx,
                const plot_style_t *style,
                const struct rect *line)
{
        if (style->stroke_type != PLOT_OP_TYPE_NONE) {
                const int path[] = {
                        draw_MOVE_TO,
                        (ro_plot_origin_x + line->x0 * 2) * 256,
                        (ro_plot_origin_y - line->y0 * 2 - 1) * 256,
                        draw_LINE_TO,
                        (ro_plot_origin_x + line->x1 * 2) * 256,
                        (ro_plot_origin_y - line->y1 * 2 - 1) * 256,
                        draw_END_PATH };
                bool dotted = false;
                bool dashed = false;
 
                if (style->stroke_type == PLOT_OP_TYPE_DOT)
                        dotted = true;
 
                if (style->stroke_type == PLOT_OP_TYPE_DASH)
                        dashed = true;
 
                return ro_plot_draw_path((const draw_path *)path,
                                plot_style_fixed_to_int(style->stroke_width),
                                style->stroke_colour,
                                dotted, dashed);
        }
        return NSERROR_OK;
}
 
 
/**
 * Plots a rectangle.
 *
 * The rectangle can be filled an outline or both controlled
 *  by the plot style The line can be solid, dotted or
 *  dashed. Top left corner at (x0,y0) and rectangle has given
 *  width and height.
 *
 * \param ctx The current redraw context.
 * \param style Style controlling the rectangle plot.
 * \param rect A rectangle defining the line to be drawn
 * \return NSERROR_OK on success else error code.
 */
static nserror
ro_plot_rectangle(const struct redraw_context *ctx,
                     const plot_style_t *style,
                     const struct rect *rect)
{
        if (style->fill_type != PLOT_OP_TYPE_NONE) {
                os_error *error;
                error = xcolourtrans_set_gcol(style->fill_colour << 8,
                                                colourtrans_USE_ECFS_GCOL,
                                                os_ACTION_OVERWRITE, 0, 0);
                if (error) {
                        NSLOG(netsurf, INFO,
                              "xcolourtrans_set_gcol: 0x%x: %s",
                              error->errnum,
                              error->errmess);
                        return NSERROR_INVALID;
                }
 
                error = xos_plot(os_MOVE_TO,
                                 ro_plot_origin_x + rect->x0 * 2,
                                 ro_plot_origin_y - rect->y1 * 2);
                if (error) {
                        NSLOG(netsurf, INFO, "xos_plot: 0x%x: %s",
                              error->errnum, error->errmess);
                        return NSERROR_INVALID;
                }
 
                error = xos_plot(os_PLOT_RECTANGLE | os_PLOT_TO,
                                 ro_plot_origin_x + rect->x1 * 2 - 1,
                                 ro_plot_origin_y - rect->y0 * 2 - 1);
                if (error) {
                        NSLOG(netsurf, INFO, "xos_plot: 0x%x: %s",
                              error->errnum, error->errmess);
                        return NSERROR_INVALID;
                }
        }
 
        if (style->stroke_type != PLOT_OP_TYPE_NONE) {
                bool dotted = false;
                bool dashed = false;
 
                const int path[] = {
                        draw_MOVE_TO,
                        (ro_plot_origin_x + rect->x0 * 2) * 256,
                        (ro_plot_origin_y - rect->y0 * 2 - 1) * 256,
                        draw_LINE_TO,
                        (ro_plot_origin_x + (rect->x1) * 2) * 256,
                        (ro_plot_origin_y - rect->y0 * 2 - 1) * 256,
                        draw_LINE_TO,
                        (ro_plot_origin_x + (rect->x1) * 2) * 256,
                        (ro_plot_origin_y - (rect->y1) * 2 - 1) * 256,
                        draw_LINE_TO,
                        (ro_plot_origin_x + rect->x0 * 2) * 256,
                        (ro_plot_origin_y - (rect->y1) * 2 - 1) * 256,
                        draw_CLOSE_LINE,
                        (ro_plot_origin_x + rect->x0 * 2) * 256,
                        (ro_plot_origin_y - rect->y0 * 2 - 1) * 256,
                        draw_END_PATH
                };
 
                if (style->stroke_type == PLOT_OP_TYPE_DOT)
                        dotted = true;
 
                if (style->stroke_type == PLOT_OP_TYPE_DASH)
                        dashed = true;
 
                ro_plot_draw_path((const draw_path *)path,
                                plot_style_fixed_to_int(style->stroke_width),
                                style->stroke_colour,
                                dotted,
                                dashed);
        }
 
        return NSERROR_OK;
}
 
 
/**
 * Plot a polygon
 *
 * Plots a filled polygon with straight lines between
 * points. The lines around the edge of the ploygon are not
 * plotted. The polygon is filled with the non-zero winding
 * rule.
 *
 * \param ctx The current redraw context.
 * \param style Style controlling the polygon plot.
 * \param p verticies of polygon
 * \param n number of verticies.
 * \return NSERROR_OK on success else error code.
 */
static nserror
ro_plot_polygon(const struct redraw_context *ctx,
                   const plot_style_t *style,
                   const int *p,
                   unsigned int n)
{
        int path[n * 3 + 2];
        unsigned int i;
        os_error *error;
 
        for (i = 0; i != n; i++) {
                path[i * 3 + 0] = draw_LINE_TO;
                path[i * 3 + 1] = (ro_plot_origin_x + p[i * 2 + 0] * 2) * 256;
                path[i * 3 + 2] = (ro_plot_origin_y - p[i * 2 + 1] * 2) * 256;
        }
        path[0] = draw_MOVE_TO;
        path[n * 3] = draw_END_PATH;
        path[n * 3 + 1] = 0;
 
        error = xcolourtrans_set_gcol(style->fill_colour << 8,
                                      0, os_ACTION_OVERWRITE, 0, 0);
        if (error) {
                NSLOG(netsurf, INFO, "xcolourtrans_set_gcol: 0x%x: %s",
                      error->errnum, error->errmess);
                return NSERROR_INVALID;
        }
        error = xdraw_fill((draw_path *) path, 0, 0, 0);
        if (error) {
                NSLOG(netsurf, INFO, "xdraw_fill: 0x%x: %s", error->errnum,
                      error->errmess);
                return NSERROR_INVALID;
        }
 
        return NSERROR_OK;
}
 
 
/**
 * Plots a path.
 *
 * Path plot consisting of cubic Bezier curves. Line and fill colour is
 *  controlled by the plot style.
 *
 * \param ctx The current redraw context.
 * \param pstyle Style controlling the path plot.
 * \param p elements of path
 * \param n nunber of elements on path
 * \param transform A transform to apply to the path.
 * \return NSERROR_OK on success else error code.
 */
static nserror
ro_plot_path(const struct redraw_context *ctx,
                const plot_style_t *pstyle,
                const float *p,
                unsigned int n,
                const float transform[6])
{
        static const draw_line_style line_style = {
                draw_JOIN_MITRED,
                draw_CAP_BUTT,
                draw_CAP_BUTT,
                0, 0x7fffffff,
                0, 0, 0, 0
        };
        int *path = 0;
        unsigned int i;
        os_trfm trfm;
        os_error *error;
 
        if (n == 0) {
                return NSERROR_OK;
        }
 
        if (p[0] != PLOTTER_PATH_MOVE) {
                NSLOG(netsurf, INFO, "path doesn't start with a move");
                goto error;
        }
 
        path = malloc(sizeof *path * (n + 10));
        if (!path) {
                NSLOG(netsurf, INFO, "out of memory");
                goto error;
        }
 
        for (i = 0; i < n; ) {
                if (p[i] == PLOTTER_PATH_MOVE) {
                        path[i] = draw_MOVE_TO;
                        path[i + 1] = p[i + 1] * 2 * 256;
                        path[i + 2] = -p[i + 2] * 2 * 256;
                        i += 3;
                } else if (p[i] == PLOTTER_PATH_CLOSE) {
                        path[i] = draw_CLOSE_LINE;
                        i++;
                } else if (p[i] == PLOTTER_PATH_LINE) {
                        path[i] = draw_LINE_TO;
                        path[i + 1] = p[i + 1] * 2 * 256;
                        path[i + 2] = -p[i + 2] * 2 * 256;
                        i += 3;
                } else if (p[i] == PLOTTER_PATH_BEZIER) {
                        path[i] = draw_BEZIER_TO;
                        path[i + 1] = p[i + 1] * 2 * 256;
                        path[i + 2] = -p[i + 2] * 2 * 256;
                        path[i + 3] = p[i + 3] * 2 * 256;
                        path[i + 4] = -p[i + 4] * 2 * 256;
                        path[i + 5] = p[i + 5] * 2 * 256;
                        path[i + 6] = -p[i + 6] * 2 * 256;
                        i += 7;
                } else {
                        NSLOG(netsurf, INFO, "bad path command %f", p[i]);
                        goto error;
                }
        }
        path[i] = draw_END_PATH;
        path[i + 1] = 0;
 
        trfm.entries[0][0] = transform[0] * 0x10000;
        trfm.entries[0][1] = transform[1] * 0x10000;
        trfm.entries[1][0] = transform[2] * 0x10000;
        trfm.entries[1][1] = transform[3] * 0x10000;
        trfm.entries[2][0] = (ro_plot_origin_x + transform[4] * 2) * 256;
        trfm.entries[2][1] = (ro_plot_origin_y - transform[5] * 2) * 256;
 
        if (pstyle->fill_colour != NS_TRANSPARENT) {
                error = xcolourtrans_set_gcol(pstyle->fill_colour << 8, 0,
                                os_ACTION_OVERWRITE, 0, 0);
                if (error) {
                        NSLOG(netsurf, INFO,
                              "xcolourtrans_set_gcol: 0x%x: %s",
                              error->errnum,
                              error->errmess);
                        goto error;
                }
 
                error = xdraw_fill((draw_path *) path, 0, &trfm, 0);
                if (error) {
                        NSLOG(netsurf, INFO, "xdraw_stroke: 0x%x: %s",
                              error->errnum, error->errmess);
                        goto error;
                }
        }
 
        if (pstyle->stroke_colour != NS_TRANSPARENT) {
                error = xcolourtrans_set_gcol(pstyle->stroke_colour << 8, 0,
                                os_ACTION_OVERWRITE, 0, 0);
                if (error) {
                        NSLOG(netsurf, INFO,
                              "xcolourtrans_set_gcol: 0x%x: %s",
                              error->errnum,
                              error->errmess);
                        goto error;
                }
 
                error = xdraw_stroke((draw_path *) path, 0, &trfm, 0,
                                plot_style_fixed_to_int(
                                                pstyle->stroke_width) * 2 * 256,
                                &line_style, 0);
                if (error) {
                        NSLOG(netsurf, INFO, "xdraw_stroke: 0x%x: %s",
                              error->errnum, error->errmess);
                        goto error;
                }
        }
 
        free(path);
        return NSERROR_OK;
 
error:
        free(path);
        return NSERROR_INVALID;
}
 
 
/**
 * Plot a bitmap
 *
 * Tiled plot of a bitmap image. (x,y) gives the top left
 * coordinate of an explicitly placed tile. From this tile the
 * image can repeat in all four directions -- up, down, left
 * and right -- to the extents given by the current clip
 * rectangle.
 *
 * The bitmap_flags say whether to tile in the x and y
 * directions. If not tiling in x or y directions, the single
 * image is plotted. The width and height give the dimensions
 * the image is to be scaled to.
 *
 * \param ctx The current redraw context.
 * \param bitmap The bitmap to plot
 * \param x The x coordinate to plot the bitmap
 * \param y The y coordiante to plot the bitmap
 * \param width The width of area to plot the bitmap into
 * \param height The height of area to plot the bitmap into
 * \param bg the background colour to alpha blend into
 * \param flags the flags controlling the type of plot operation
 * \return NSERROR_OK on success else error code.
 */
static nserror
ro_plot_bitmap(const struct redraw_context *ctx,
               struct bitmap *bitmap,
               int x, int y,
               int width,
               int height,
               colour bg,
               bitmap_flags_t flags)
{
        const uint8_t *buffer;
 
        buffer = riscos_bitmap_get_buffer(bitmap);
        if (!buffer) {
                NSLOG(netsurf, INFO, "bitmap_get_buffer failed");
                return NSERROR_INVALID;
        }
 
        if (!image_redraw(bitmap->sprite_area,
                        ro_plot_origin_x + x * 2,
                        ro_plot_origin_y - y * 2,
                        width, height,
                        bitmap->width,
                        bitmap->height,
                        bg,
                        flags & BITMAPF_REPEAT_X, flags & BITMAPF_REPEAT_Y,
                        flags & BITMAPF_REPEAT_X || flags & BITMAPF_REPEAT_Y,
                        riscos_bitmap_get_opaque(bitmap) ? IMAGE_PLOT_TINCT_OPAQUE :
                         IMAGE_PLOT_TINCT_ALPHA)) {
                return NSERROR_INVALID;
        }
        return NSERROR_OK;
}
 
 
/**
 * Text plotting.
 *
 * \param ctx The current redraw context.
 * \param fstyle plot style for this text
 * \param x x coordinate
 * \param y y coordinate
 * \param text UTF-8 string to plot
 * \param length length of string, in bytes
 * \return NSERROR_OK on success else error code.
 */
static nserror
ro_plot_text(const struct redraw_context *ctx,
                const struct plot_font_style *fstyle,
                int x,
                int y,
                const char *text,
                size_t length)
{
        os_error *error;
 
        error = xcolourtrans_set_font_colours(font_CURRENT,
                        fstyle->background << 8, fstyle->foreground << 8,
                        14, 0, 0, 0);
        if (error) {
                NSLOG(netsurf, INFO,
                      "xcolourtrans_set_font_colours: 0x%x: %s",
                      error->errnum,
                      error->errmess);
                return NSERROR_INVALID;
        }
 
        if (!nsfont_paint(fstyle, text, length,
                        ro_plot_origin_x + x * 2,
                          ro_plot_origin_y - y * 2)) {
                return NSERROR_INVALID;
        }
        return NSERROR_OK;
}
 
 
/**
 * RISC OS plotter operation table
 */
const struct plotter_table ro_plotters = {
        .rectangle = ro_plot_rectangle,
        .line = ro_plot_line,
        .polygon = ro_plot_polygon,
        .clip = ro_plot_clip,
        .text = ro_plot_text,
        .disc = ro_plot_disc,
        .arc = ro_plot_arc,
        .bitmap = ro_plot_bitmap,
        .path = ro_plot_path,
        .option_knockout = true,
};