render.c.svn-base

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#include "fitz-base.h"
#include "fitz-world.h"
#include "fitz-draw.h"

#ifdef _MSC_VER
#define noDebug printf
#ifndef DEBUG
#define DEBUG
#endif
#else
#define noDEBUG(args...) printf(args)
#ifndef DEBUG
#define DEBUG(args...)
#endif
#endif
#define QUANT(x,a) (((int)((x) * (a))) / (a))
#define HSUBPIX 5.0
#define VSUBPIX 5.0

#define FNONE 0
#define FOVER 1
#define FRGB 4

static fz_error *rendernode(fz_renderer *gc, fz_node *node, fz_matrix ctm);

fz_error *
fz_newrenderer(fz_renderer **gcp, fz_colorspace *pcm, int maskonly, int gcmem)
{
	fz_error *error;
	fz_renderer *gc;

	gc = fz_malloc(sizeof(fz_renderer));
	if (!gc)
		return fz_outofmem;

	gc->maskonly = maskonly;
	gc->model = pcm;
	gc->cache = nil;
	gc->gel = nil;
	gc->ael = nil;

	error = fz_newglyphcache(&gc->cache, gcmem / 24, gcmem);
	if (error)
		goto cleanup;

	error = fz_newgel(&gc->gel);
	if (error)
		goto cleanup;

	error = fz_newael(&gc->ael);
	if (error)
		goto cleanup;

	gc->dest = nil;
	gc->over = nil;
	gc->argb[0] = 255;
	gc->argb[1] = 0;
	gc->argb[2] = 0;
	gc->argb[3] = 0;
	gc->argb[4] = 0;
	gc->argb[5] = 0;
	gc->argb[6] = 0;
	gc->flag = 0;

	*gcp = gc;
	return fz_okay;

cleanup:
	if (gc->model) fz_dropcolorspace(gc->model);
	if (gc->cache) fz_dropglyphcache(gc->cache);
	if (gc->gel) fz_dropgel(gc->gel);
	if (gc->ael) fz_dropael(gc->ael);
	fz_free(gc);
	return error;
}

void
fz_droprenderer(fz_renderer *gc)
{
	if (gc->dest) fz_droppixmap(gc->dest);
	if (gc->over) fz_droppixmap(gc->over);

	if (gc->model) fz_dropcolorspace(gc->model);
	if (gc->cache) fz_dropglyphcache(gc->cache);
	if (gc->gel) fz_dropgel(gc->gel);
	if (gc->ael) fz_dropael(gc->ael);
	fz_free(gc);
}

/*
 * Transform
 */

static fz_error *
rendertransform(fz_renderer *gc, fz_transformnode *transform, fz_matrix ctm)
{
	fz_error *error;
DEBUG("transform [%g %g %g %g %g %g]\n",
transform->m.a, transform->m.b,
transform->m.c, transform->m.d,
transform->m.e, transform->m.f);
DEBUG("{\n");
	ctm = fz_concat(transform->m, ctm);
	error = rendernode(gc, transform->super.first, ctm);
DEBUG("}\n");
	return error;
}

/*
 * Color
 */

static fz_error *
rendersolid(fz_renderer *gc, fz_solidnode *solid, fz_matrix ctm)
{
	fz_error *error;
	float rgb[3];
	unsigned char a, r, g, b;
	unsigned char *p;
	int n;

	if (gc->maskonly)
		return fz_throw("assert: mask only renderer");
	if (gc->model->n != 3)
		return fz_throw("assert: non-rgb renderer");

	fz_convertcolor(solid->cs, solid->samples, gc->model, rgb);
	gc->argb[0] = solid->a * 255;
	gc->argb[1] = rgb[0] * solid->a * 255;
	gc->argb[2] = rgb[1] * solid->a * 255;
	gc->argb[3] = rgb[2] * solid->a * 255;
	gc->argb[4] = rgb[0] * 255;
	gc->argb[5] = rgb[1] * 255;
	gc->argb[6] = rgb[2] * 255;

DEBUG("solid %s [%d %d %d %d];\n", solid->cs->name, gc->argb[0], gc->argb[1], gc->argb[2], gc->argb[3]);

	if (gc->flag == FOVER)
	{
		p = gc->over->samples;
		n = gc->over->w * gc->over->h;
	}
	else
	{
		error = fz_newpixmapwithrect(&gc->dest, gc->clip, 4);
		if (error)
			return error;
		p = gc->dest->samples;
		n = gc->dest->w * gc->dest->h;
	}
	
	a = gc->argb[0];
	r = gc->argb[1];
	g = gc->argb[2];
	b = gc->argb[3];
	if (((unsigned)p & 3)) {
	while (n--)
	{
		p[0] = a;
		p[1] = r;
		p[2] = g;
		p[3] = b;
		p += 4;
	}
	}
	else
	{
		unsigned *pw = (unsigned *)p;
#if BYTE_ORDER == LITTLE_ENDIAN
		unsigned argb = a | (r << 8) | (g << 16) | (b << 24);
#else
		unsigned argb = (a << 24) | (r << 16) | (g << 8) | b;
#endif
		while (n--)
		{
			*pw++ = argb;
		}
	}

	return fz_okay;
}

/*
 * Path
 */

static fz_error *
renderpath(fz_renderer *gc, fz_pathnode *path, fz_matrix ctm)
{
	fz_error *error;
	float flatness;
	fz_irect gbox;
	fz_irect clip;
	float expansion = fz_matrixexpansion(ctm);

	flatness = 0.3 / expansion;
	if (flatness < 0.1)
		flatness = 0.1;

	fz_resetgel(gc->gel, gc->clip);

	if (path->paint == FZ_STROKE)
	{
		float lw = path->linewidth;
		/* Check for hairline */
		if (lw * expansion < 0.1) {
			lw = 1.0f / expansion;
		}
		if (path->dash)
			error = fz_dashpath(gc->gel, path, ctm, flatness, lw);
		else
			error = fz_strokepath(gc->gel, path, ctm, flatness, lw);
	}
	else
		error = fz_fillpath(gc->gel, path, ctm, flatness);
	if (error)
		return error;

	fz_sortgel(gc->gel);

	gbox = fz_boundgel(gc->gel);
	clip = fz_intersectirects(gc->clip, gbox);

	if (fz_isemptyrect(clip))
		return fz_okay;

DEBUG("path %s;\n", path->paint == FZ_STROKE ? "stroke" : "fill");

	if (gc->flag & FRGB)
	{
DEBUG(" path rgb %d %d %d %d, %d %d %d\n", gc->argb[0], gc->argb[1], gc->argb[2], gc->argb[3], gc->argb[4], gc->argb[5], gc->argb[6]);
		return fz_scanconvert(gc->gel, gc->ael, path->paint == FZ_EOFILL,
					clip, gc->over, gc->argb, 1);
	}
	else if (gc->flag & FOVER)
	{
		return fz_scanconvert(gc->gel, gc->ael, path->paint == FZ_EOFILL,
					clip, gc->over, nil, 1);
	}
	else
	{
		error = fz_newpixmapwithrect(&gc->dest, clip, 1);
		if (error)
			return error;
		fz_clearpixmap(gc->dest);
		return fz_scanconvert(gc->gel, gc->ael, path->paint == FZ_EOFILL,
					clip, gc->dest, nil, 0);
	}
}

/*
 * Text
 */

static void drawglyph(fz_renderer *gc, fz_pixmap *dst, fz_glyph *src, int xorig, int yorig)
{
	unsigned char *dp, *sp;
	int w, h;

	int dx0 = dst->x;
	int dy0 = dst->y;
	int dx1 = dst->x + dst->w;
	int dy1 = dst->y + dst->h;

	int x0 = xorig + src->x;
	int y0 = yorig + src->y;
	int x1 = x0 + src->w;
	int y1 = y0 + src->h;

	int sx0 = 0;
	int sy0 = 0;
	int sx1 = src->w;
	int sy1 = src->h;

	if (x1 <= dx0 || x0 >= dx1) return;
	if (y1 <= dy0 || y0 >= dy1) return;
	if (x0 < dx0) { sx0 += dx0 - x0; x0 = dx0; }
	if (y0 < dy0) { sy0 += dy0 - y0; y0 = dy0; }
	if (x1 > dx1) { sx1 += dx1 - x1; x1 = dx1; }
	if (y1 > dy1) { sy1 += dy1 - y1; y1 = dy1; }

	sp = src->samples + (sy0 * src->w + sx0);
	dp = dst->samples + ((y0 - dst->y) * dst->w + (x0 - dst->x)) * dst->n;

	w = sx1 - sx0;
	h = sy1 - sy0;

	switch (gc->flag)
	{
	case FNONE:
		assert(dst->n == 1);
		fz_text_1o1(sp, src->w, dp, dst->w, w, h);
		break;

	case FOVER:
		assert(dst->n == 1);
		fz_text_1o1(sp, src->w, dp, dst->w, w, h);
		break;

	case FOVER | FRGB:
		assert(dst->n == 4);
		fz_text_w4i1o4(gc->argb, sp, src->w, dp, dst->w * 4, w, h);
		break;

	default:
		assert(!"impossible flag in text span function");
	}
}

static fz_error *
rendertext(fz_renderer *gc, fz_textnode *text, fz_matrix ctm)
{
	fz_error *error;
	fz_irect tbox;
	fz_irect clip;
	fz_matrix tm, trm;
	fz_glyph glyph;
	int i, x, y, cid;

	tbox = fz_roundrect(fz_boundnode((fz_node*)text, ctm));
	clip = fz_intersectirects(gc->clip, tbox);

DEBUG("text %s n=%d [%g %g %g %g];\n",
text->font->name, text->len,
text->trm.a, text->trm.b, text->trm.c, text->trm.d);

	if (fz_isemptyrect(clip))
		return fz_okay;

	if (!(gc->flag & FOVER))
	{
		error = fz_newpixmapwithrect(&gc->dest, clip, 1);
		if (error)
			return error;
		fz_clearpixmap(gc->dest);
	}

	tm = text->trm;

	for (i = 0; i < text->len; i++)
	{
		cid = text->els[i].cid;
		tm.e = text->els[i].x;
		tm.f = text->els[i].y;
		trm = fz_concat(tm, ctm);
		x = fz_floor(trm.e);
		y = fz_floor(trm.f);
		trm.e = QUANT(trm.e - fz_floor(trm.e), HSUBPIX);
		trm.f = QUANT(trm.f - fz_floor(trm.f), VSUBPIX);

		error = fz_renderglyph(gc->cache, &glyph, text->font, cid, trm);
		if (error)
			return error;

		if (!(gc->flag & FOVER))
			drawglyph(gc, gc->dest, &glyph, x, y);
		else
			drawglyph(gc, gc->over, &glyph, x, y);
	}

	return fz_okay;
}

/*
 * Image
 */

static inline void
calcimagescale(fz_matrix ctm, int w, int h, int *odx, int *ody)
{
	float sx, sy;
	int dx, dy;

	sx = sqrt(ctm.a * ctm.a + ctm.b * ctm.b);
	dx = 1;
	while (((w+dx-1)/dx)/sx > 2.0 && (w+dx-1)/dx > 1)
		dx++;

	sy = sqrt(ctm.c * ctm.c + ctm.d * ctm.d);
	dy = 1;
	while (((h+dy-1)/dy)/sy > 2.0 && (h+dy-1)/dy > 1)
		dy++;

	*odx = dx;
	*ody = dy;
}

static fz_error *
renderimage(fz_renderer *gc, fz_imagenode *node, fz_matrix ctm)
{
	fz_error *error;
	fz_image *image = node->image;
	fz_irect bbox;
	fz_irect clip;
	int dx, dy;
	fz_pixmap *tile;
	fz_pixmap *temp;
	fz_matrix imgmat;
	fz_matrix invmat;
	int fa, fb, fc, fd;
	int u0, v0;
	int x0, y0;
	int w, h;
	int tileheight;

DEBUG("image %dx%d %d+%d %s\n{\n", image->w, image->h, image->n, image->a, image->cs?image->cs->name:"(nil)");

	bbox = fz_roundrect(fz_boundnode((fz_node*)node, ctm));
	clip = fz_intersectirects(gc->clip, bbox);

	if (fz_isemptyrect(clip))
		return fz_okay;
        if (image->w == 0 || image->h == 0)
                return fz_okay;

	if (image->n + image->a == 0)
		return fz_okay;

	calcimagescale(ctm, image->w, image->h, &dx, &dy);

	/* try to fit tile into a typical L2 cachce */
	tileheight = 512 * 1024 / (image->w * (image->n + image->a));
	/* tileheight must be an even multiple of dy, except for last band */
	tileheight = (tileheight + dy - 1) / dy * dy;

	if ((dx != 1 || dy != 1) && image->h > tileheight) {
		int y = 0;

		DEBUG("  load image tile size = %dx%d\n", image->w, tileheight);
		error = fz_newpixmap(&tile, 0, 0, image->w,
				     tileheight, image->n + 1);
		if (error)
			return error;

		error = fz_newscaledpixmap(&temp, image->w, image->h, image->n + 1, dx, dy);
		if (error)
			goto cleanup;

		do {
			if (y + tileheight > image->h)
				tileheight = image->h - y;
			tile->y = y;
			tile->h = tileheight;
			DEBUG("  tile xywh=%d %d %d %d sxsy=1/%d 1/%d\n",
			      0, y, image->w, tileheight, dx, dy);
			error = image->loadtile(image, tile);
			if (error)
				goto cleanup1;

			error = fz_scalepixmaptile(temp, 0, y, tile, dx, dy);
			if (error)
				goto cleanup1;

			y += tileheight;
		} while (y < image->h);

		fz_droppixmap(tile);
		tile = temp;
	}
	else {


DEBUG("  load image\n");
		error = fz_newpixmap(&tile, 0, 0, image->w, image->h, image->n + 1);
		if (error)
			return error;

		error = image->loadtile(image, tile);
		if (error)
			goto cleanup;

		if (dx != 1 || dy != 1)
		{
DEBUG("  scale image 1/%d 1/%d\n", dx, dy);
			error = fz_scalepixmap(&temp, tile, dx, dy);
			if (error)
				goto cleanup;
			fz_droppixmap(tile);
			tile = temp;
		}
	}

	if (image->cs && image->cs != gc->model)
	{
DEBUG("  convert from %s to %s\n", image->cs->name, gc->model->name);
		error = fz_newpixmap(&temp, tile->x, tile->y, tile->w, tile->h, gc->model->n + 1);
		if (error)