framebuffer.c

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/*
 * Copyright 2008 Vincent Sanders <vince@simtec.co.uk>
 *
 * Framebuffer interface
 *
 * 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/>.
 */
 
#include <stdio.h>
#include <stdbool.h>
#include <stdlib.h>
#include <string.h>
 
#include <libnsfb.h>
#include <libnsfb_plot.h>
#include <libnsfb_event.h>
#include <libnsfb_cursor.h>
 
#include "utils/utils.h"
#include "utils/log.h"
#include "utils/utf8.h"
#include "netsurf/browser_window.h"
#include "netsurf/plotters.h"
#include "netsurf/bitmap.h"
 
#include "framebuffer/gui.h"
#include "framebuffer/fbtk.h"
#include "framebuffer/framebuffer.h"
#include "framebuffer/font.h"
#include "framebuffer/bitmap.h"
 
/* netsurf framebuffer library handle */
static nsfb_t *nsfb;
 
 
/**
 * \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
framebuffer_plot_clip(const struct redraw_context *ctx, const struct rect *clip)
{
        nsfb_bbox_t nsfb_clip;
        nsfb_clip.x0 = clip->x0;
        nsfb_clip.y0 = clip->y0;
        nsfb_clip.x1 = clip->x1;
        nsfb_clip.y1 = clip->y1;
 
        if (!nsfb_plot_set_clip(nsfb, &nsfb_clip)) {
                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
framebuffer_plot_arc(const struct redraw_context *ctx,
               const plot_style_t *style,
               int x, int y, int radius, int angle1, int angle2)
{
        if (!nsfb_plot_arc(nsfb, x, y, radius, angle1, angle2, style->fill_colour)) {
                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 x coordinate of circle centre.
 * \param y y coordinate of circle centre.
 * \param radius circle radius.
 * \return NSERROR_OK on success else error code.
 */
static nserror
framebuffer_plot_disc(const struct redraw_context *ctx,
                const plot_style_t *style,
                int x, int y, int radius)
{
        nsfb_bbox_t ellipse;
        ellipse.x0 = x - radius;
        ellipse.y0 = y - radius;
        ellipse.x1 = x + radius;
        ellipse.y1 = y + radius;
 
        if (style->fill_type != PLOT_OP_TYPE_NONE) {
                nsfb_plot_ellipse_fill(nsfb, &ellipse, style->fill_colour);
        }
 
        if (style->stroke_type != PLOT_OP_TYPE_NONE) {
                nsfb_plot_ellipse(nsfb, &ellipse, style->stroke_colour);
        }
        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
framebuffer_plot_line(const struct redraw_context *ctx,
                const plot_style_t *style,
                const struct rect *line)
{
        nsfb_bbox_t rect;
        nsfb_plot_pen_t pen;
 
        rect.x0 = line->x0;
        rect.y0 = line->y0;
        rect.x1 = line->x1;
        rect.y1 = line->y1;
 
        if (style->stroke_type != PLOT_OP_TYPE_NONE) {
 
                if (style->stroke_type == PLOT_OP_TYPE_DOT) {
                        pen.stroke_type = NFSB_PLOT_OPTYPE_PATTERN;
                        pen.stroke_pattern = 0xAAAAAAAA;
                } else if (style->stroke_type == PLOT_OP_TYPE_DASH) {
                        pen.stroke_type = NFSB_PLOT_OPTYPE_PATTERN;
                        pen.stroke_pattern = 0xF0F0F0F0;
                } else {
                        pen.stroke_type = NFSB_PLOT_OPTYPE_SOLID;
                }
 
                pen.stroke_colour = style->stroke_colour;
                pen.stroke_width = plot_style_fixed_to_int(style->stroke_width);
                nsfb_plot_line(nsfb, &rect, &pen);
        }
 
        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 nsrect A rectangle defining the line to be drawn
 * \return NSERROR_OK on success else error code.
 */
static nserror
framebuffer_plot_rectangle(const struct redraw_context *ctx,
                     const plot_style_t *style,
                     const struct rect *nsrect)
{
        nsfb_bbox_t rect;
        bool dotted = false;
        bool dashed = false;
 
        rect.x0 = nsrect->x0;
        rect.y0 = nsrect->y0;
        rect.x1 = nsrect->x1;
        rect.y1 = nsrect->y1;
 
        if (style->fill_type != PLOT_OP_TYPE_NONE) {
                nsfb_plot_rectangle_fill(nsfb, &rect, style->fill_colour);
        }
 
        if (style->stroke_type != PLOT_OP_TYPE_NONE) {
                if (style->stroke_type == PLOT_OP_TYPE_DOT) {
                        dotted = true;
                }
 
                if (style->stroke_type == PLOT_OP_TYPE_DASH) {
                        dashed = true;
                }
 
                nsfb_plot_rectangle(nsfb, &rect,
                                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
framebuffer_plot_polygon(const struct redraw_context *ctx,
                   const plot_style_t *style,
                   const int *p,
                   unsigned int n)
{
        if (!nsfb_plot_polygon(nsfb, p, n, style->fill_colour)) {
                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
framebuffer_plot_path(const struct redraw_context *ctx,
                const plot_style_t *pstyle,
                const float *p,
                unsigned int n,
                const float transform[6])
{
        NSLOG(netsurf, INFO, "path unimplemented");
        return NSERROR_OK;
}
 
 
/**
 * 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
framebuffer_plot_bitmap(const struct redraw_context *ctx,
                  struct bitmap *bitmap,
                  int x, int y,
                  int width,
                  int height,
                  colour bg,
                  bitmap_flags_t flags)
{
        nsfb_bbox_t loc;
        nsfb_bbox_t clipbox;
        bool repeat_x = (flags & BITMAPF_REPEAT_X);
        bool repeat_y = (flags & BITMAPF_REPEAT_Y);
        int bmwidth;
        int bmheight;
        int bmstride;
        enum nsfb_format_e bmformat;
        unsigned char *bmptr;
        nsfb_t *bm = (nsfb_t *)bitmap;
 
        /* x and y define coordinate of top left of of the initial explicitly
         * placed tile. The width and height are the image scaling and the
         * bounding box defines the extent of the repeat (which may go in all
         * four directions from the initial tile).
         */
 
        if (!(repeat_x || repeat_y)) {
                /* Not repeating at all, so just plot it */
                loc.x0 = x;
                loc.y0 = y;
                loc.x1 = loc.x0 + width;
                loc.y1 = loc.y0 + height;
 
                if (!nsfb_plot_copy(bm, NULL, nsfb, &loc)) {
                        return NSERROR_INVALID;
                }
                return NSERROR_OK;
        }
 
        nsfb_plot_get_clip(nsfb, &clipbox);
        nsfb_get_geometry(bm, &bmwidth, &bmheight, &bmformat);
        nsfb_get_buffer(bm, &bmptr, &bmstride);
 
        /* Optimise tiled plots of 1x1 bitmaps by replacing with a flat fill
         * of the area.  Can only be done when image is fully opaque. */
        if ((bmwidth == 1) && (bmheight == 1)) {
                if ((*(nsfb_colour_t *)bmptr & 0xff000000) != 0) {
                        if (!nsfb_plot_rectangle_fill(nsfb, &clipbox,
                                                      *(nsfb_colour_t *)bmptr)) {
                                return NSERROR_INVALID;
                        }
                        return NSERROR_OK;
                }
        }
 
        /* Optimise tiled plots of bitmaps scaled to 1x1 by replacing with
         * a flat fill of the area.  Can only be done when image is fully
         * opaque. */
        if ((width == 1) && (height == 1)) {
                if (framebuffer_bitmap_get_opaque(bm)) {
                        /** TODO: Currently using top left pixel. Maybe centre
                         *        pixel or average value would be better. */
                        if (!nsfb_plot_rectangle_fill(nsfb, &clipbox,
                                                      *(nsfb_colour_t *)bmptr)) {
                                return NSERROR_INVALID;
                        }
                        return NSERROR_OK;
                }
        }
 
        /* get left most tile position */
        if (repeat_x) {
                for (; x > clipbox.x0; x -= width);
        }
 
        /* get top most tile position */
        if (repeat_y) {
                for (; y > clipbox.y0; y -= height);
        }
 
        /* set up top left tile location */
        loc.x0 = x;
        loc.y0 = y;
        loc.x1 = loc.x0 + width;
        loc.y1 = loc.y0 + height;
 
        /* plot tiling across and down to extents */
        nsfb_plot_bitmap_tiles(nsfb, &loc,
                        repeat_x ? ((clipbox.x1 - x) + width  - 1) / width  : 1,
                        repeat_y ? ((clipbox.y1 - y) + height - 1) / height : 1,
                        (nsfb_colour_t *)bmptr, bmwidth, bmheight,
                        bmstride * 8 / 32, bmformat == NSFB_FMT_ABGR8888);
 
        return NSERROR_OK;
}
 
 
#ifdef FB_USE_FREETYPE
/**
 * 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
framebuffer_plot_text(const struct redraw_context *ctx,
                const struct plot_font_style *fstyle,
                int x,
                int y,
                const char *text,
                size_t length)
{
        uint32_t ucs4;
        size_t nxtchr = 0;
        FT_Glyph glyph;
        FT_BitmapGlyph bglyph;
        nsfb_bbox_t loc;
 
        while (nxtchr < length) {
                ucs4 = utf8_to_ucs4(text + nxtchr, length - nxtchr);
                nxtchr = utf8_next(text, length, nxtchr);
 
                glyph = fb_getglyph(fstyle, ucs4);
                if (glyph == NULL)
                        continue;
 
                if (glyph->format == FT_GLYPH_FORMAT_BITMAP) {
                        bglyph = (FT_BitmapGlyph)glyph;
 
                        loc.x0 = x + bglyph->left;
                        loc.y0 = y - bglyph->top;
                        loc.x1 = loc.x0 + bglyph->bitmap.width;
                        loc.y1 = loc.y0 + bglyph->bitmap.rows;
 
                        /* now, draw to our target surface */
                        if (bglyph->bitmap.pixel_mode == FT_PIXEL_MODE_MONO) {
                            nsfb_plot_glyph1(nsfb,
                                             &loc,
                                             bglyph->bitmap.buffer,
                                             bglyph->bitmap.pitch,
                                             fstyle->foreground);
                        } else {
                            nsfb_plot_glyph8(nsfb,
                                             &loc,
                                             bglyph->bitmap.buffer,
                                             bglyph->bitmap.pitch,
                                             fstyle->foreground);
                        }
                }
                x += glyph->advance.x >> 16;
 
        }
        return NSERROR_OK;
 
}
 
#else
 
/**
 * 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
framebuffer_plot_text(const struct redraw_context *ctx,
                const struct plot_font_style *fstyle,
                int x,
                int y,
                const char *text,
                size_t length)
{
    enum fb_font_style style = fb_get_font_style(fstyle);
    int size = fb_get_font_size(fstyle);
    const uint8_t *chrp;
    size_t nxtchr = 0;
    nsfb_bbox_t loc;
    uint32_t ucs4;
    int p = FB_FONT_PITCH * size;
    int w = FB_FONT_WIDTH * size;
    int h = FB_FONT_HEIGHT * size;
 
    y -= ((h * 3) / 4);
    /* the coord is the bottom-left of the pixels offset by 1 to make
     * it work since fb coords are the top-left of pixels */
    y += 1;
 
    while (nxtchr < length) {
        ucs4 = utf8_to_ucs4(text + nxtchr, length - nxtchr);
        nxtchr = utf8_next(text, length, nxtchr);
 
        if (!codepoint_displayable(ucs4))
                continue;
 
        loc.x0 = x;
        loc.y0 = y;
        loc.x1 = loc.x0 + w;
        loc.y1 = loc.y0 + h;
 
        chrp = fb_get_glyph(ucs4, style, size);
        nsfb_plot_glyph1(nsfb, &loc, chrp, p, fstyle->foreground);
 
        x += w;
 
    }
 
    return NSERROR_OK;
}
#endif
 
 
/** framebuffer plot operation table */
const struct plotter_table fb_plotters = {
        .clip = framebuffer_plot_clip,
        .arc = framebuffer_plot_arc,
        .disc = framebuffer_plot_disc,
        .line = framebuffer_plot_line,
        .rectangle = framebuffer_plot_rectangle,
        .polygon = framebuffer_plot_polygon,
        .path = framebuffer_plot_path,
        .bitmap = framebuffer_plot_bitmap,
        .text = framebuffer_plot_text,
        .option_knockout = true,
};
 
 
static bool framebuffer_format_from_bpp(int bpp, enum nsfb_format_e *fmt)
{
        switch (bpp) {
        case 32:
                *fmt = NSFB_FMT_XRGB8888;
                break;
 
        case 24:
                *fmt = NSFB_FMT_RGB888;
                break;
 
        case 16:
                *fmt = NSFB_FMT_RGB565;
                break;
 
        case 8:
                *fmt = NSFB_FMT_I8;
                break;
 
        case 4:
                *fmt = NSFB_FMT_I4;
                break;
 
        case 1:
                *fmt = NSFB_FMT_I1;
                break;
 
        default:
                NSLOG(netsurf, INFO, "Bad bits per pixel (%d)\n", bpp);
                return false;
        }
 
        return true;
}
 
 
 
nsfb_t *
framebuffer_initialise(const char *fename, int width, int height, int bpp)
{
    enum nsfb_type_e fbtype;
    enum nsfb_format_e fbfmt;
 
    /* bpp is a proxy for the framebuffer format */
    if (framebuffer_format_from_bpp(bpp, &fbfmt) == false) {
        return NULL;
    }
 
    fbtype = nsfb_type_from_name(fename);
    if (fbtype == NSFB_SURFACE_NONE) {
        NSLOG(netsurf, INFO,
              "The %s surface is not available from libnsfb\n", fename);
        return NULL;
    }
 
    nsfb = nsfb_new(fbtype);
    if (nsfb == NULL) {
        NSLOG(netsurf, INFO, "Unable to create %s fb surface\n", fename);
        return NULL;
    }
 
    if (nsfb_set_geometry(nsfb, width, height, fbfmt) == -1) {
        NSLOG(netsurf, INFO, "Unable to set surface geometry\n");
        nsfb_free(nsfb);
        return NULL;
    }
 
    nsfb_cursor_init(nsfb);
 
    if (nsfb_init(nsfb) == -1) {
        NSLOG(netsurf, INFO, "Unable to initialise nsfb surface\n");
        nsfb_free(nsfb);
        return NULL;
    }
 
    return nsfb;
 
}
 
bool
framebuffer_resize(nsfb_t *nsfb, int width, int height, int bpp)
{
    enum nsfb_format_e fbfmt;
 
    /* bpp is a proxy for the framebuffer format */
    if (framebuffer_format_from_bpp(bpp, &fbfmt) == false) {
        return false;
    }
 
    if (nsfb_set_geometry(nsfb, width, height, fbfmt) == -1) {
        NSLOG(netsurf, INFO, "Unable to change surface geometry\n");
        return false;
    }
 
    return true;
 
}
 
void
framebuffer_finalise(void)
{
    nsfb_free(nsfb);
}
 
bool
framebuffer_set_cursor(struct fbtk_bitmap *bm)
{
    return nsfb_cursor_set(nsfb, (nsfb_colour_t *)bm->pixdata, bm->width, bm->height, bm->width, bm->hot_x, bm->hot_y);
}
 
nsfb_t *framebuffer_set_surface(nsfb_t *new_nsfb)
{
        nsfb_t *old_nsfb;
        old_nsfb = nsfb;
        nsfb = new_nsfb;
        return old_nsfb;
}