+++ /dev/null
-/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
-/*
- * art_rgba_svp.c: A slightly modified version of art_rgb_svp to render into rgba buffer
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Library General Public License
- * as published by the Free Software Foundation; either version 2 of
- * the License, or (at your option) any later version.
- *
- * This program 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 Library General Public License for more details.
- *
- * You should have received a copy of the GNU Library General Public
- * License along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- *
- * Authors:
- * Raph Levien <raph@acm.org>
- * Lauris Kaplinski <lauris@ariman.ee>
- *
- * Copyright (C) 1998 Raph Levien
- *
- */
-
-#define SP_ART_RGBA_SVP_C
-
-/* Render a sorted vector path into an RGBA buffer. */
-
-#include <libart_lgpl/art_misc.h>
-#include <libart_lgpl/art_svp.h>
-#include <libart_lgpl/art_svp_render_aa.h>
-#include <libart_lgpl/art_rgb.h>
-
-#include "art_rgba_svp.h"
-#include "unused.h"
-
-static void art_rgba_fill_run(
- art_u8 * linebuf,
- art_u8 r,
- art_u8 g,
- art_u8 b,
- int n);
-static void art_rgba_run_alpha(
- art_u8 * linebuf,
- art_u8 r,
- art_u8 g,
- art_u8 b,
- int alpha,
- int n);
-
-typedef struct _ArtRgbaSVPAlphaData ArtRgbaSVPAlphaData;
-
-struct _ArtRgbaSVPAlphaData {
- int alphatab[256];
- art_u8 r, g, b, alpha;
- art_u8 *buf;
- int rowstride;
- int libart_x0, libart_x1;
-};
-
-static void art_rgba_svp_alpha_callback(
- void *callback_data,
- int UNUSED(y),
- int start,
- ArtSVPRenderAAStep * steps,
- int n_steps)
-{
- ArtRgbaSVPAlphaData *data = callback_data;
- art_u8 *linebuf;
- int run_x0, run_x1;
- art_u32 running_sum = start;
- int libart_x0, libart_x1;
- int k;
- art_u8 r, g, b;
- int *alphatab;
- int alpha;
-
- linebuf = data->buf;
- libart_x0 = data->libart_x0;
- libart_x1 = data->libart_x1;
-
- r = data->r;
- g = data->g;
- b = data->b;
- alphatab = data->alphatab;
-
- if (n_steps > 0) {
- run_x1 = steps[0].x;
- if (run_x1 > libart_x0) {
- alpha = (running_sum >> 16) & 0xff;
- if (alpha)
- art_rgba_run_alpha(linebuf,
- r, g, b, alphatab[alpha],
- run_x1 - libart_x0);
- }
-
- /* render the steps into tmpbuf */
- for (k = 0; k < n_steps - 1; k++) {
- running_sum += steps[k].delta;
- run_x0 = run_x1;
- run_x1 = steps[k + 1].x;
- if (run_x1 > run_x0) {
- alpha = (running_sum >> 16) & 0xff;
- if (alpha)
- art_rgba_run_alpha(linebuf + (run_x0 - libart_x0) * 4,
- r, g, b, alphatab[alpha],
- run_x1 - run_x0);
- }
- }
- running_sum += steps[k].delta;
- if (libart_x1 > run_x1) {
- alpha = (running_sum >> 16) & 0xff;
- if (alpha)
- art_rgba_run_alpha(linebuf + (run_x1 - libart_x0) * 4,
- r, g, b, alphatab[alpha],
- libart_x1 - run_x1);
- }
- } else {
- alpha = (running_sum >> 16) & 0xff;
- if (alpha)
- art_rgba_run_alpha(linebuf,
- r, g, b, alphatab[alpha],
- libart_x1 - libart_x0);
- }
-
- data->buf += data->rowstride;
-}
-
-static void art_rgba_svp_alpha_opaque_callback(
- void *callback_data,
- int UNUSED(y),
- int start,
- ArtSVPRenderAAStep * steps,
- int n_steps)
-{
- ArtRgbaSVPAlphaData *data = callback_data;
- art_u8 *linebuf;
- int run_x0, run_x1;
- art_u32 running_sum = start;
- int libart_x0, libart_x1;
- int k;
- art_u8 r, g, b;
- int *alphatab;
- int alpha;
-
- linebuf = data->buf;
- libart_x0 = data->libart_x0;
- libart_x1 = data->libart_x1;
-
- r = data->r;
- g = data->g;
- b = data->b;
- alphatab = data->alphatab;
-
- if (n_steps > 0) {
- run_x1 = steps[0].x;
- if (run_x1 > libart_x0) {
- alpha = running_sum >> 16;
- if (alpha) {
- if (alpha >= 255)
- art_rgba_fill_run(linebuf, r, g, b, run_x1 - libart_x0);
- else
- art_rgba_run_alpha(linebuf,
- r, g, b, alphatab[alpha],
- run_x1 - libart_x0);
- }
- }
-
- /* render the steps into tmpbuf */
- for (k = 0; k < n_steps - 1; k++) {
- running_sum += steps[k].delta;
- run_x0 = run_x1;
- run_x1 = steps[k + 1].x;
- if (run_x1 > run_x0) {
- alpha = running_sum >> 16;
- if (alpha) {
- if (alpha >= 255)
- art_rgba_fill_run(linebuf + (run_x0 - libart_x0) * 4,
- r, g, b, run_x1 - run_x0);
- else
- art_rgba_run_alpha(linebuf + (run_x0 - libart_x0) * 4,
- r, g, b, alphatab[alpha],
- run_x1 - run_x0);
- }
- }
- }
- running_sum += steps[k].delta;
- if (libart_x1 > run_x1) {
- alpha = running_sum >> 16;
- if (alpha) {
- if (alpha >= 255)
- art_rgba_fill_run(linebuf + (run_x1 - libart_x0) * 4,
- r, g, b, libart_x1 - run_x1);
- else
- art_rgba_run_alpha(linebuf + (run_x1 - libart_x0) * 4,
- r, g, b, alphatab[alpha],
- libart_x1 - run_x1);
- }
- }
- } else {
- alpha = running_sum >> 16;
- if (alpha) {
- if (alpha >= 255)
- art_rgba_fill_run(linebuf, r, g, b, libart_x1 - libart_x0);
- else
- art_rgba_run_alpha(linebuf,
- r, g, b, alphatab[alpha],
- libart_x1 - libart_x0);
- }
- }
-
- data->buf += data->rowstride;
-}
-
-/**
- * gnome_print_art_rgba_svp_alpha: Alpha-composite sorted vector path over RGBA buffer.
- * @svp: The source sorted vector path.
- * @libart_x0: Left coordinate of destination rectangle.
- * @libart_y0: Top coordinate of destination rectangle.
- * @libart_x1: Right coordinate of destination rectangle.
- * @libart_y1: Bottom coordinate of destination rectangle.
- * @rgba: Color in 0xRRGGBBAA format.
- * @buf: Destination RGB buffer.
- * @rowstride: Rowstride of @buf buffer.
- * @alphagamma: #ArtAlphaGamma for gamma-correcting the compositing.
- *
- * Renders the shape specified with @svp over the @buf RGB buffer.
- * @libart_x1 - @x0 specifies the width, and @libart_y1 - @libart_y0 specifies the height,
- * of the rectangle rendered. The new pixels are stored starting at
- * the first byte of @buf. Thus, the @x0 and @libart_y0 parameters specify
- * an offset within @svp, and may be tweaked as a way of doing
- * integer-pixel translations without fiddling with @svp itself.
- *
- * The @rgba argument specifies the color for the rendering. Pixels of
- * entirely 0 winding number are left untouched. Pixels of entirely
- * 1 winding number have the color @rgba composited over them (ie,
- * are replaced by the red, green, blue components of @rgba if the alpha
- * component is 0xff). Pixels of intermediate coverage are interpolated
- * according to the rule in @alphagamma, or default to linear if
- * @alphagamma is NULL.
- **/
-void gnome_print_art_rgba_svp_alpha(
- const ArtSVP * svp,
- int libart_x0,
- int libart_y0,
- int libart_x1,
- int libart_y1,
- art_u32 rgba,
- art_u8 * buf,
- int rowstride,
- ArtAlphaGamma UNUSED(*alphagamma))
-{
- ArtRgbaSVPAlphaData data;
- int r, g, b, alpha;
- int i;
- int a, da;
-
- r = rgba >> 24;
- g = (rgba >> 16) & 0xff;
- b = (rgba >> 8) & 0xff;
- alpha = rgba & 0xff;
-
- data.r = r;
- data.g = g;
- data.b = b;
- data.alpha = alpha;
-
- a = 0x8000;
- da = (alpha * 66051 + 0x80) >> 8; /* 66051 equals 2 ^ 32 / (255 * 255) */
-
- for (i = 0; i < 256; i++) {
- data.alphatab[i] = a >> 16;
- a += da;
- }
-
- data.buf = buf;
- data.rowstride = rowstride;
- data.libart_x0 = libart_x0;
- data.libart_x1 = libart_x1;
- if (alpha == 255)
- art_svp_render_aa(svp, libart_x0, libart_y0, libart_x1, libart_y1,
- art_rgba_svp_alpha_opaque_callback, &data);
- else
- art_svp_render_aa(svp, libart_x0, libart_y0, libart_x1, libart_y1,
- art_rgba_svp_alpha_callback, &data);
-}
-
-static void art_rgba_fill_run(
- art_u8 * buf,
- art_u8 r,
- art_u8 g,
- art_u8 b,
- int n)
-{
- int i;
-
- for (i = 0; i < n; i++) {
- *buf++ = r;
- *buf++ = g;
- *buf++ = b;
- *buf++ = 255;
- }
-}
-
-/* fixme: this */
-
-static void art_rgba_run_alpha(
- art_u8 * buf,
- art_u8 r,
- art_u8 g,
- art_u8 b,
- int alpha,
- int n)
-{
- int i;
- int br, bg, bb, ba;
- int cr, cg, cb;
-
- for (i = 0; i < n; i++) {
- br = *(buf + 0);
- bg = *(buf + 1);
- bb = *(buf + 2);
- ba = *(buf + 3);
-
- cr = (br * ba + 0x80) >> 8;
- cg = (bg * ba + 0x80) >> 8;
- cb = (bb * ba + 0x80) >> 8;
-
- *buf++ = cr + (((r - cr) * alpha + 0x80) >> 8);
- *buf++ = cg + (((g - cg) * alpha + 0x80) >> 8);
- *buf++ = cb + (((b - cb) * alpha + 0x80) >> 8);
- *buf++ = ba + (((255 - ba) * alpha + 0x80) >> 8);
- }
-}
projects / rrdtool.git / blobdiff