kolibrios/contrib/media/updf/pdf/pdf_shade.c

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#include "fitz.h"
#include "mupdf.h"
#define HUGENUM 32000 /* how far to extend axial/radial shadings */
#define FUNSEGS 32 /* size of sampled mesh for function-based shadings */
#define RADSEGS 32 /* how many segments to generate for radial meshes */
#define SUBDIV 3 /* how many levels to subdivide patches */
struct vertex
{
float x, y;
float c[FZ_MAX_COLORS];
};
static void
pdf_grow_mesh(fz_shade *shade, int amount)
{
if (shade->mesh_len + amount < shade->mesh_cap)
return;
if (shade->mesh_cap == 0)
shade->mesh_cap = 1024;
while (shade->mesh_len + amount > shade->mesh_cap)
shade->mesh_cap = (shade->mesh_cap * 3) / 2;
shade->mesh = fz_realloc(shade->mesh, shade->mesh_cap, sizeof(float));
}
static void
pdf_add_vertex(fz_shade *shade, struct vertex *v)
{
int ncomp = shade->use_function ? 1 : shade->colorspace->n;
int i;
pdf_grow_mesh(shade, 2 + ncomp);
shade->mesh[shade->mesh_len++] = v->x;
shade->mesh[shade->mesh_len++] = v->y;
for (i = 0; i < ncomp; i++)
shade->mesh[shade->mesh_len++] = v->c[i];
}
static void
pdf_add_triangle(fz_shade *shade,
struct vertex *v0,
struct vertex *v1,
struct vertex *v2)
{
pdf_add_vertex(shade, v0);
pdf_add_vertex(shade, v1);
pdf_add_vertex(shade, v2);
}
static void
pdf_add_quad(fz_shade *shade,
struct vertex *v0,
struct vertex *v1,
struct vertex *v2,
struct vertex *v3)
{
pdf_add_triangle(shade, v0, v1, v3);
pdf_add_triangle(shade, v1, v3, v2);
}
/* Subdivide and tesselate tensor-patches */
typedef struct pdf_tensor_patch_s pdf_tensor_patch;
struct pdf_tensor_patch_s
{
fz_point pole[4][4];
float color[4][FZ_MAX_COLORS];
};
static void
triangulate_patch(pdf_tensor_patch p, fz_shade *shade)
{
struct vertex v0, v1, v2, v3;
v0.x = p.pole[0][0].x;
v0.y = p.pole[0][0].y;
memcpy(v0.c, p.color[0], sizeof(v0.c));
v1.x = p.pole[0][3].x;
v1.y = p.pole[0][3].y;
memcpy(v1.c, p.color[1], sizeof(v1.c));
v2.x = p.pole[3][3].x;
v2.y = p.pole[3][3].y;
memcpy(v2.c, p.color[2], sizeof(v2.c));
v3.x = p.pole[3][0].x;
v3.y = p.pole[3][0].y;
memcpy(v3.c, p.color[3], sizeof(v3.c));
pdf_add_quad(shade, &v0, &v1, &v2, &v3);
}
static inline void midcolor(float *c, float *c1, float *c2)
{
int i;
for (i = 0; i < FZ_MAX_COLORS; i++)
c[i] = (c1[i] + c2[i]) * 0.5f;
}
static void
split_curve(fz_point *pole, fz_point *q0, fz_point *q1, int polestep)
{
/*
split bezier curve given by control points pole[0]..pole[3]
using de casteljau algo at midpoint and build two new
bezier curves q0[0]..q0[3] and q1[0]..q1[3]. all indices
should be multiplies by polestep == 1 for vertical bezier
curves in patch and == 4 for horizontal bezier curves due
to C's multi-dimensional matrix memory layout.
*/
float x12 = (pole[1 * polestep].x + pole[2 * polestep].x) * 0.5f;
float y12 = (pole[1 * polestep].y + pole[2 * polestep].y) * 0.5f;
q0[1 * polestep].x = (pole[0 * polestep].x + pole[1 * polestep].x) * 0.5f;
q0[1 * polestep].y = (pole[0 * polestep].y + pole[1 * polestep].y) * 0.5f;
q1[2 * polestep].x = (pole[2 * polestep].x + pole[3 * polestep].x) * 0.5f;
q1[2 * polestep].y = (pole[2 * polestep].y + pole[3 * polestep].y) * 0.5f;
q0[2 * polestep].x = (q0[1 * polestep].x + x12) * 0.5f;
q0[2 * polestep].y = (q0[1 * polestep].y + y12) * 0.5f;
q1[1 * polestep].x = (x12 + q1[2 * polestep].x) * 0.5f;
q1[1 * polestep].y = (y12 + q1[2 * polestep].y) * 0.5f;
q0[3 * polestep].x = (q0[2 * polestep].x + q1[1 * polestep].x) * 0.5f;
q0[3 * polestep].y = (q0[2 * polestep].y + q1[1 * polestep].y) * 0.5f;
q1[0 * polestep].x = (q0[2 * polestep].x + q1[1 * polestep].x) * 0.5f;
q1[0 * polestep].y = (q0[2 * polestep].y + q1[1 * polestep].y) * 0.5f;
q0[0 * polestep].x = pole[0 * polestep].x;
q0[0 * polestep].y = pole[0 * polestep].y;
q1[3 * polestep].x = pole[3 * polestep].x;
q1[3 * polestep].y = pole[3 * polestep].y;
}
static void
split_stripe(pdf_tensor_patch *p, pdf_tensor_patch *s0, pdf_tensor_patch *s1)
{
/*
split all horizontal bezier curves in patch,
creating two new patches with half the width.
*/
split_curve(&p->pole[0][0], &s0->pole[0][0], &s1->pole[0][0], 4);
split_curve(&p->pole[0][1], &s0->pole[0][1], &s1->pole[0][1], 4);
split_curve(&p->pole[0][2], &s0->pole[0][2], &s1->pole[0][2], 4);
split_curve(&p->pole[0][3], &s0->pole[0][3], &s1->pole[0][3], 4);
/* interpolate the colors for the two new patches. */
memcpy(s0->color[0], p->color[0], sizeof(s0->color[0]));
memcpy(s0->color[1], p->color[1], sizeof(s0->color[1]));
midcolor(s0->color[2], p->color[1], p->color[2]);
midcolor(s0->color[3], p->color[0], p->color[3]);
memcpy(s1->color[0], s0->color[3], sizeof(s1->color[0]));
memcpy(s1->color[1], s0->color[2], sizeof(s1->color[1]));
memcpy(s1->color[2], p->color[2], sizeof(s1->color[2]));
memcpy(s1->color[3], p->color[3], sizeof(s1->color[3]));
}
static void
draw_stripe(pdf_tensor_patch *p, fz_shade *shade, int depth)
{
pdf_tensor_patch s0, s1;
/* split patch into two half-height patches */
split_stripe(p, &s0, &s1);
depth--;
if (depth == 0)
{
/* if no more subdividing, draw two new patches... */
triangulate_patch(s0, shade);
triangulate_patch(s1, shade);
}
else
{
/* ...otherwise, continue subdividing. */
draw_stripe(&s0, shade, depth);
draw_stripe(&s1, shade, depth);
}
}
static void
split_patch(pdf_tensor_patch *p, pdf_tensor_patch *s0, pdf_tensor_patch *s1)
{
/*
split all vertical bezier curves in patch,
creating two new patches with half the height.
*/
split_curve(p->pole[0], s0->pole[0], s1->pole[0], 1);
split_curve(p->pole[1], s0->pole[1], s1->pole[1], 1);
split_curve(p->pole[2], s0->pole[2], s1->pole[2], 1);
split_curve(p->pole[3], s0->pole[3], s1->pole[3], 1);
/* interpolate the colors for the two new patches. */
memcpy(s0->color[0], p->color[0], sizeof(s0->color[0]));
midcolor(s0->color[1], p->color[0], p->color[1]);
midcolor(s0->color[2], p->color[2], p->color[3]);
memcpy(s0->color[3], p->color[3], sizeof(s0->color[3]));
memcpy(s1->color[0], s0->color[1], sizeof(s1->color[0]));
memcpy(s1->color[1], p->color[1], sizeof(s1->color[1]));
memcpy(s1->color[2], p->color[2], sizeof(s1->color[2]));
memcpy(s1->color[3], s0->color[2], sizeof(s1->color[3]));
}
static void
draw_patch(fz_shade *shade, pdf_tensor_patch *p, int depth, int origdepth)
{
pdf_tensor_patch s0, s1;
/* split patch into two half-width patches */
split_patch(p, &s0, &s1);
depth--;
if (depth == 0)
{
/* if no more subdividing, draw two new patches... */
draw_stripe(&s0, shade, origdepth);
draw_stripe(&s1, shade, origdepth);
}
else
{
/* ...otherwise, continue subdividing. */
draw_patch(shade, &s0, depth, origdepth);
draw_patch(shade, &s1, depth, origdepth);
}
}
static fz_point
pdf_compute_tensor_interior(
fz_point a, fz_point b, fz_point c, fz_point d,
fz_point e, fz_point f, fz_point g, fz_point h)
{
fz_point pt;
/* see equations at page 330 in pdf 1.7 */
pt.x = -4 * a.x;
pt.x += 6 * (b.x + c.x);
pt.x += -2 * (d.x + e.x);
pt.x += 3 * (f.x + g.x);
pt.x += -1 * h.x;
pt.x /= 9;
pt.y = -4 * a.y;
pt.y += 6 * (b.y + c.y);
pt.y += -2 * (d.y + e.y);
pt.y += 3 * (f.y + g.y);
pt.y += -1 * h.y;
pt.y /= 9;
return pt;
}
static void
pdf_make_tensor_patch(pdf_tensor_patch *p, int type, fz_point *pt)
{
if (type == 6)
{
/* see control point stream order at page 325 in pdf 1.7 */
p->pole[0][0] = pt[0];
p->pole[0][1] = pt[1];
p->pole[0][2] = pt[2];
p->pole[0][3] = pt[3];
p->pole[1][3] = pt[4];
p->pole[2][3] = pt[5];
p->pole[3][3] = pt[6];
p->pole[3][2] = pt[7];
p->pole[3][1] = pt[8];
p->pole[3][0] = pt[9];
p->pole[2][0] = pt[10];
p->pole[1][0] = pt[11];
/* see equations at page 330 in pdf 1.7 */
p->pole[1][1] = pdf_compute_tensor_interior(
p->pole[0][0], p->pole[0][1], p->pole[1][0], p->pole[0][3],
p->pole[3][0], p->pole[3][1], p->pole[1][3], p->pole[3][3]);
p->pole[1][2] = pdf_compute_tensor_interior(
p->pole[0][3], p->pole[0][2], p->pole[1][3], p->pole[0][0],
p->pole[3][3], p->pole[3][2], p->pole[1][0], p->pole[3][0]);
p->pole[2][1] = pdf_compute_tensor_interior(
p->pole[3][0], p->pole[3][1], p->pole[2][0], p->pole[3][3],
p->pole[0][0], p->pole[0][1], p->pole[2][3], p->pole[0][3]);
p->pole[2][2] = pdf_compute_tensor_interior(
p->pole[3][3], p->pole[3][2], p->pole[2][3], p->pole[3][0],
p->pole[0][3], p->pole[0][2], p->pole[2][0], p->pole[0][0]);
}
else if (type == 7)
{
/* see control point stream order at page 330 in pdf 1.7 */
p->pole[0][0] = pt[0];
p->pole[0][1] = pt[1];
p->pole[0][2] = pt[2];
p->pole[0][3] = pt[3];
p->pole[1][3] = pt[4];
p->pole[2][3] = pt[5];
p->pole[3][3] = pt[6];
p->pole[3][2] = pt[7];
p->pole[3][1] = pt[8];
p->pole[3][0] = pt[9];
p->pole[2][0] = pt[10];
p->pole[1][0] = pt[11];
p->pole[1][1] = pt[12];
p->pole[1][2] = pt[13];
p->pole[2][2] = pt[14];
p->pole[2][1] = pt[15];
}
}
/* Sample various functions into lookup tables */
static void
pdf_sample_composite_shade_function(fz_shade *shade, pdf_function *func, float t0, float t1)
{
int i;
float t;
for (i = 0; i < 256; i++)
{
t = t0 + (i / 255.0f) * (t1 - t0);
pdf_eval_function(func, &t, 1, shade->function[i], shade->colorspace->n);
shade->function[i][shade->colorspace->n] = 1;
}
}
static void
pdf_sample_component_shade_function(fz_shade *shade, int funcs, pdf_function **func, float t0, float t1)
{
int i, k;
float t;
for (i = 0; i < 256; i++)
{
t = t0 + (i / 255.0f) * (t1 - t0);
for (k = 0; k < funcs; k++)
pdf_eval_function(func[k], &t, 1, &shade->function[i][k], 1);
shade->function[i][k] = 1;
}
}
static void
pdf_sample_shade_function(fz_shade *shade, int funcs, pdf_function **func, float t0, float t1)
{
shade->use_function = 1;
if (funcs == 1)
pdf_sample_composite_shade_function(shade, func[0], t0, t1);
else
pdf_sample_component_shade_function(shade, funcs, func, t0, t1);
}
/* Type 1-3 -- Function-based, axial and radial shadings */
static void
pdf_load_function_based_shading(fz_shade *shade, pdf_xref *xref, fz_obj *dict, pdf_function *func)
{
fz_obj *obj;
float x0, y0, x1, y1;
fz_matrix matrix;
struct vertex v[4];
int xx, yy;
float x, y;
float xn, yn;
int i;
x0 = y0 = 0;
x1 = y1 = 1;
obj = fz_dict_gets(dict, "Domain");
if (fz_array_len(obj) == 4)
{
x0 = fz_to_real(fz_array_get(obj, 0));
x1 = fz_to_real(fz_array_get(obj, 1));
y0 = fz_to_real(fz_array_get(obj, 2));
y1 = fz_to_real(fz_array_get(obj, 3));
}
matrix = fz_identity;
obj = fz_dict_gets(dict, "Matrix");
if (fz_array_len(obj) == 6)
matrix = pdf_to_matrix(obj);
for (yy = 0; yy < FUNSEGS; yy++)
{
y = y0 + (y1 - y0) * yy / FUNSEGS;
yn = y0 + (y1 - y0) * (yy + 1) / FUNSEGS;
for (xx = 0; xx < FUNSEGS; xx++)
{
x = x0 + (x1 - x0) * xx / FUNSEGS;
xn = x0 + (x1 - x0) * (xx + 1) / FUNSEGS;
v[0].x = x; v[0].y = y;
v[1].x = xn; v[1].y = y;
v[2].x = xn; v[2].y = yn;
v[3].x = x; v[3].y = yn;
for (i = 0; i < 4; i++)
{
fz_point pt;
float fv[2];
fv[0] = v[i].x;
fv[1] = v[i].y;
pdf_eval_function(func, fv, 2, v[i].c, shade->colorspace->n);
pt.x = v[i].x;
pt.y = v[i].y;
pt = fz_transform_point(matrix, pt);
v[i].x = pt.x;
v[i].y = pt.y;
}
pdf_add_quad(shade, &v[0], &v[1], &v[2], &v[3]);
}
}
}
static void
pdf_load_axial_shading(fz_shade *shade, pdf_xref *xref, fz_obj *dict, int funcs, pdf_function **func)
{
fz_obj *obj;
float d0, d1;
int e0, e1;
float x0, y0, x1, y1;
struct vertex p1, p2;
obj = fz_dict_gets(dict, "Coords");
x0 = fz_to_real(fz_array_get(obj, 0));
y0 = fz_to_real(fz_array_get(obj, 1));
x1 = fz_to_real(fz_array_get(obj, 2));
y1 = fz_to_real(fz_array_get(obj, 3));
d0 = 0;
d1 = 1;
obj = fz_dict_gets(dict, "Domain");
if (fz_array_len(obj) == 2)
{
d0 = fz_to_real(fz_array_get(obj, 0));
d1 = fz_to_real(fz_array_get(obj, 1));
}
e0 = e1 = 0;
obj = fz_dict_gets(dict, "Extend");
if (fz_array_len(obj) == 2)
{
e0 = fz_to_bool(fz_array_get(obj, 0));
e1 = fz_to_bool(fz_array_get(obj, 1));
}
pdf_sample_shade_function(shade, funcs, func, d0, d1);
shade->type = FZ_LINEAR;
shade->extend[0] = e0;
shade->extend[1] = e1;
p1.x = x0;
p1.y = y0;
p1.c[0] = 0;
pdf_add_vertex(shade, &p1);
p2.x = x1;
p2.y = y1;
p2.c[0] = 0;
pdf_add_vertex(shade, &p2);
}
static void
pdf_load_radial_shading(fz_shade *shade, pdf_xref *xref, fz_obj *dict, int funcs, pdf_function **func)
{
fz_obj *obj;
float d0, d1;
int e0, e1;
float x0, y0, r0, x1, y1, r1;
struct vertex p1, p2;
obj = fz_dict_gets(dict, "Coords");
x0 = fz_to_real(fz_array_get(obj, 0));
y0 = fz_to_real(fz_array_get(obj, 1));
r0 = fz_to_real(fz_array_get(obj, 2));
x1 = fz_to_real(fz_array_get(obj, 3));
y1 = fz_to_real(fz_array_get(obj, 4));
r1 = fz_to_real(fz_array_get(obj, 5));
d0 = 0;
d1 = 1;
obj = fz_dict_gets(dict, "Domain");
if (fz_array_len(obj) == 2)
{
d0 = fz_to_real(fz_array_get(obj, 0));
d1 = fz_to_real(fz_array_get(obj, 1));
}
e0 = e1 = 0;
obj = fz_dict_gets(dict, "Extend");
if (fz_array_len(obj) == 2)
{
e0 = fz_to_bool(fz_array_get(obj, 0));
e1 = fz_to_bool(fz_array_get(obj, 1));
}
pdf_sample_shade_function(shade, funcs, func, d0, d1);
shade->type = FZ_RADIAL;
shade->extend[0] = e0;
shade->extend[1] = e1;
p1.x = x0;
p1.y = y0;
p1.c[0] = r0;
pdf_add_vertex(shade, &p1);
p2.x = x1;
p2.y = y1;
p2.c[0] = r1;
pdf_add_vertex(shade, &p2);
}
/* Type 4-7 -- Triangle and patch mesh shadings */
static inline float read_sample(fz_stream *stream, int bits, float min, float max)
{
/* we use pow(2,x) because (1<<x) would overflow the math on 32-bit samples */
float bitscale = 1 / (powf(2, bits) - 1);
return min + fz_read_bits(stream, bits) * (max - min) * bitscale;
}
struct mesh_params
{
int vprow;
int bpflag;
int bpcoord;
int bpcomp;
float x0, x1;
float y0, y1;
float c0[FZ_MAX_COLORS];
float c1[FZ_MAX_COLORS];
};
static void
pdf_load_mesh_params(pdf_xref *xref, fz_obj *dict, struct mesh_params *p)
{
fz_obj *obj;
int i, n;
p->x0 = p->y0 = 0;
p->x1 = p->y1 = 1;
for (i = 0; i < FZ_MAX_COLORS; i++)
{
p->c0[i] = 0;
p->c1[i] = 1;
}
p->vprow = fz_to_int(fz_dict_gets(dict, "VerticesPerRow"));
p->bpflag = fz_to_int(fz_dict_gets(dict, "BitsPerFlag"));
p->bpcoord = fz_to_int(fz_dict_gets(dict, "BitsPerCoordinate"));
p->bpcomp = fz_to_int(fz_dict_gets(dict, "BitsPerComponent"));
obj = fz_dict_gets(dict, "Decode");
if (fz_array_len(obj) >= 6)
{
n = (fz_array_len(obj) - 4) / 2;
p->x0 = fz_to_real(fz_array_get(obj, 0));
p->x1 = fz_to_real(fz_array_get(obj, 1));
p->y0 = fz_to_real(fz_array_get(obj, 2));
p->y1 = fz_to_real(fz_array_get(obj, 3));
for (i = 0; i < n; i++)
{
p->c0[i] = fz_to_real(fz_array_get(obj, 4 + i * 2));
p->c1[i] = fz_to_real(fz_array_get(obj, 5 + i * 2));
}
}
if (p->vprow < 2)
p->vprow = 2;
if (p->bpflag != 2 && p->bpflag != 4 && p->bpflag != 8)
p->bpflag = 8;
if (p->bpcoord != 1 && p->bpcoord != 2 && p->bpcoord != 4 &&
p->bpcoord != 8 && p->bpcoord != 12 && p->bpcoord != 16 &&
p->bpcoord != 24 && p->bpcoord != 32)
p->bpcoord = 8;
if (p->bpcomp != 1 && p->bpcomp != 2 && p->bpcomp != 4 &&
p->bpcomp != 8 && p->bpcomp != 12 && p->bpcomp != 16)
p->bpcomp = 8;
}
static void
pdf_load_type4_shade(fz_shade *shade, pdf_xref *xref, fz_obj *dict,
int funcs, pdf_function **func, fz_stream *stream)
{
struct mesh_params p;
struct vertex va, vb, vc, vd;
int ncomp;
int flag;
int i;
pdf_load_mesh_params(xref, dict, &p);
if (funcs > 0)
{
ncomp = 1;
pdf_sample_shade_function(shade, funcs, func, p.c0[0], p.c1[0]);
}
else
ncomp = shade->colorspace->n;
while (!fz_is_eof_bits(stream))
{
flag = fz_read_bits(stream, p.bpflag);
vd.x = read_sample(stream, p.bpcoord, p.x0, p.x1);
vd.y = read_sample(stream, p.bpcoord, p.y0, p.y1);
for (i = 0; i < ncomp; i++)
vd.c[i] = read_sample(stream, p.bpcomp, p.c0[i], p.c1[i]);
switch (flag)
{
case 0: /* start new triangle */
va = vd;
fz_read_bits(stream, p.bpflag);
vb.x = read_sample(stream, p.bpcoord, p.x0, p.x1);
vb.y = read_sample(stream, p.bpcoord, p.y0, p.y1);
for (i = 0; i < ncomp; i++)
vb.c[i] = read_sample(stream, p.bpcomp, p.c0[i], p.c1[i]);
fz_read_bits(stream, p.bpflag);
vc.x = read_sample(stream, p.bpcoord, p.x0, p.x1);
vc.y = read_sample(stream, p.bpcoord, p.y0, p.y1);
for (i = 0; i < ncomp; i++)
vc.c[i] = read_sample(stream, p.bpcomp, p.c0[i], p.c1[i]);
pdf_add_triangle(shade, &va, &vb, &vc);
break;
case 1: /* Vb, Vc, Vd */
va = vb;
vb = vc;
vc = vd;
pdf_add_triangle(shade, &va, &vb, &vc);
break;
case 2: /* Va, Vc, Vd */
vb = vc;
vc = vd;
pdf_add_triangle(shade, &va, &vb, &vc);
break;
}
}
}
static void
pdf_load_type5_shade(fz_shade *shade, pdf_xref *xref, fz_obj *dict,
int funcs, pdf_function **func, fz_stream *stream)
{
struct mesh_params p;
struct vertex *buf, *ref;
int first;
int ncomp;
int i, k;
pdf_load_mesh_params(xref, dict, &p);
if (funcs > 0)
{
ncomp = 1;
pdf_sample_shade_function(shade, funcs, func, p.c0[0], p.c1[0]);
}
else
ncomp = shade->colorspace->n;
ref = fz_calloc(p.vprow, sizeof(struct vertex));
buf = fz_calloc(p.vprow, sizeof(struct vertex));
first = 1;
while (!fz_is_eof_bits(stream))
{
for (i = 0; i < p.vprow; i++)
{
buf[i].x = read_sample(stream, p.bpcoord, p.x0, p.x1);
buf[i].y = read_sample(stream, p.bpcoord, p.y0, p.y1);
for (k = 0; k < ncomp; k++)
buf[i].c[k] = read_sample(stream, p.bpcomp, p.c0[k], p.c1[k]);
}
if (!first)
for (i = 0; i < p.vprow - 1; i++)
pdf_add_quad(shade,
&ref[i], &ref[i+1], &buf[i+1], &buf[i]);
memcpy(ref, buf, p.vprow * sizeof(struct vertex));
first = 0;
}
free(ref);
free(buf);
}
/* Type 6 & 7 -- Patch mesh shadings */
static void
pdf_load_type6_shade(fz_shade *shade, pdf_xref *xref, fz_obj *dict,
int funcs, pdf_function **func, fz_stream *stream)
{
struct mesh_params p;
int haspatch, hasprevpatch;
float prevc[4][FZ_MAX_COLORS];
fz_point prevp[12];
int ncomp;
int i, k;
pdf_load_mesh_params(xref, dict, &p);
if (funcs > 0)
{
ncomp = 1;
pdf_sample_shade_function(shade, funcs, func, p.c0[0], p.c1[0]);
}
else
ncomp = shade->colorspace->n;
hasprevpatch = 0;
while (!fz_is_eof_bits(stream))
{
float c[4][FZ_MAX_COLORS];
fz_point v[12];
int startcolor;
int startpt;
int flag;
flag = fz_read_bits(stream, p.bpflag);
if (flag == 0)
{
startpt = 0;
startcolor = 0;
}
else
{
startpt = 4;
startcolor = 2;
}
for (i = startpt; i < 12; i++)
{
v[i].x = read_sample(stream, p.bpcoord, p.x0, p.x1);
v[i].y = read_sample(stream, p.bpcoord, p.y0, p.y1);
}
for (i = startcolor; i < 4; i++)
{
for (k = 0; k < ncomp; k++)
c[i][k] = read_sample(stream, p.bpcomp, p.c0[k], p.c1[k]);
}
haspatch = 0;
if (flag == 0)
{
haspatch = 1;
}
else if (flag == 1 && hasprevpatch)
{
v[0] = prevp[3];
v[1] = prevp[4];
v[2] = prevp[5];
v[3] = prevp[6];
memcpy(c[0], prevc[1], ncomp * sizeof(float));
memcpy(c[1], prevc[2], ncomp * sizeof(float));
haspatch = 1;
}
else if (flag == 2 && hasprevpatch)
{
v[0] = prevp[6];
v[1] = prevp[7];
v[2] = prevp[8];
v[3] = prevp[9];
memcpy(c[0], prevc[2], ncomp * sizeof(float));
memcpy(c[1], prevc[3], ncomp * sizeof(float));
haspatch = 1;
}
else if (flag == 3 && hasprevpatch)
{
v[0] = prevp[ 9];
v[1] = prevp[10];
v[2] = prevp[11];
v[3] = prevp[ 0];
memcpy(c[0], prevc[3], ncomp * sizeof(float));
memcpy(c[1], prevc[0], ncomp * sizeof(float));
haspatch = 1;
}
if (haspatch)
{
pdf_tensor_patch patch;
pdf_make_tensor_patch(&patch, 6, v);
for (i = 0; i < 4; i++)
memcpy(patch.color[i], c[i], ncomp * sizeof(float));
draw_patch(shade, &patch, SUBDIV, SUBDIV);
for (i = 0; i < 12; i++)
prevp[i] = v[i];
for (i = 0; i < 4; i++)
memcpy(prevc[i], c[i], ncomp * sizeof(float));
hasprevpatch = 1;
}
}
}
static void
pdf_load_type7_shade(fz_shade *shade, pdf_xref *xref, fz_obj *dict,
int funcs, pdf_function **func, fz_stream *stream)
{
struct mesh_params p;
int haspatch, hasprevpatch;
float prevc[4][FZ_MAX_COLORS];
fz_point prevp[16];
int ncomp;
int i, k;
pdf_load_mesh_params(xref, dict, &p);
if (funcs > 0)
{
ncomp = 1;
pdf_sample_shade_function(shade, funcs, func, p.c0[0], p.c1[0]);
}
else
ncomp = shade->colorspace->n;
hasprevpatch = 0;
while (!fz_is_eof_bits(stream))
{
float c[4][FZ_MAX_COLORS];
fz_point v[16];
int startcolor;
int startpt;
int flag;
flag = fz_read_bits(stream, p.bpflag);
if (flag == 0)
{
startpt = 0;
startcolor = 0;
}
else
{
startpt = 4;
startcolor = 2;
}
for (i = startpt; i < 16; i++)
{
v[i].x = read_sample(stream, p.bpcoord, p.x0, p.x1);
v[i].y = read_sample(stream, p.bpcoord, p.y0, p.y1);
}
for (i = startcolor; i < 4; i++)
{
for (k = 0; k < ncomp; k++)
c[i][k] = read_sample(stream, p.bpcomp, p.c0[k], p.c1[k]);
}
haspatch = 0;
if (flag == 0)
{
haspatch = 1;
}
else if (flag == 1 && hasprevpatch)
{
v[0] = prevp[3];
v[1] = prevp[4];
v[2] = prevp[5];
v[3] = prevp[6];
memcpy(c[0], prevc[1], ncomp * sizeof(float));
memcpy(c[1], prevc[2], ncomp * sizeof(float));
haspatch = 1;
}
else if (flag == 2 && hasprevpatch)
{
v[0] = prevp[6];
v[1] = prevp[7];
v[2] = prevp[8];
v[3] = prevp[9];
memcpy(c[0], prevc[2], ncomp * sizeof(float));
memcpy(c[1], prevc[3], ncomp * sizeof(float));
haspatch = 1;
}
else if (flag == 3 && hasprevpatch)
{
v[0] = prevp[ 9];
v[1] = prevp[10];
v[2] = prevp[11];
v[3] = prevp[ 0];
memcpy(c[0], prevc[3], ncomp * sizeof(float));
memcpy(c[1], prevc[0], ncomp * sizeof(float));
haspatch = 1;
}
if (haspatch)
{
pdf_tensor_patch patch;
pdf_make_tensor_patch(&patch, 7, v);
for (i = 0; i < 4; i++)
memcpy(patch.color[i], c[i], ncomp * sizeof(float));
draw_patch(shade, &patch, SUBDIV, SUBDIV);
for (i = 0; i < 16; i++)
prevp[i] = v[i];
for (i = 0; i < 4; i++)
memcpy(prevc[i], c[i], FZ_MAX_COLORS * sizeof(float));
hasprevpatch = 1;
}
}
}
/* Load all of the shading dictionary parameters, then switch on the shading type. */
static fz_error
pdf_load_shading_dict(fz_shade **shadep, pdf_xref *xref, fz_obj *dict, fz_matrix transform)
{
fz_error error;
fz_shade *shade;
pdf_function *func[FZ_MAX_COLORS] = { NULL };
fz_stream *stream = NULL;
fz_obj *obj;
int funcs;
int type;
int i;
shade = fz_malloc(sizeof(fz_shade));
shade->refs = 1;
shade->type = FZ_MESH;
shade->use_background = 0;
shade->use_function = 0;
shade->matrix = transform;
shade->bbox = fz_infinite_rect;
shade->extend[0] = 0;
shade->extend[1] = 0;
shade->mesh_len = 0;
shade->mesh_cap = 0;
shade->mesh = NULL;
shade->colorspace = NULL;
funcs = 0;
obj = fz_dict_gets(dict, "ShadingType");
type = fz_to_int(obj);
obj = fz_dict_gets(dict, "ColorSpace");
if (!obj)
{
fz_drop_shade(shade);
return fz_throw("shading colorspace is missing");
}
error = pdf_load_colorspace(&shade->colorspace, xref, obj);
if (error)
{
fz_drop_shade(shade);
return fz_rethrow(error, "cannot load colorspace (%d %d R)", fz_to_num(obj), fz_to_gen(obj));
}
obj = fz_dict_gets(dict, "Background");
if (obj)
{
shade->use_background = 1;
for (i = 0; i < shade->colorspace->n; i++)
shade->background[i] = fz_to_real(fz_array_get(obj, i));
}
obj = fz_dict_gets(dict, "BBox");
if (fz_is_array(obj))
{
shade->bbox = pdf_to_rect(obj);
}
obj = fz_dict_gets(dict, "Function");
if (fz_is_dict(obj))
{
funcs = 1;
error = pdf_load_function(&func[0], xref, obj);
if (error)
{
error = fz_rethrow(error, "cannot load shading function (%d %d R)", fz_to_num(obj), fz_to_gen(obj));
goto cleanup;
}
}
else if (fz_is_array(obj))
{
funcs = fz_array_len(obj);
if (funcs != 1 && funcs != shade->colorspace->n)
{
error = fz_throw("incorrect number of shading functions");
goto cleanup;
}
for (i = 0; i < funcs; i++)
{
error = pdf_load_function(&func[i], xref, fz_array_get(obj, i));
if (error)
{
error = fz_rethrow(error, "cannot load shading function (%d %d R)", fz_to_num(obj), fz_to_gen(obj));
goto cleanup;
}
}
}
if (type >= 4 && type <= 7)
{
error = pdf_open_stream(&stream, xref, fz_to_num(dict), fz_to_gen(dict));
if (error)
{
error = fz_rethrow(error, "cannot open shading stream (%d %d R)", fz_to_num(dict), fz_to_gen(dict));
goto cleanup;
}
}
switch (type)
{
case 1: pdf_load_function_based_shading(shade, xref, dict, func[0]); break;
case 2: pdf_load_axial_shading(shade, xref, dict, funcs, func); break;
case 3: pdf_load_radial_shading(shade, xref, dict, funcs, func); break;
case 4: pdf_load_type4_shade(shade, xref, dict, funcs, func, stream); break;
case 5: pdf_load_type5_shade(shade, xref, dict, funcs, func, stream); break;
case 6: pdf_load_type6_shade(shade, xref, dict, funcs, func, stream); break;
case 7: pdf_load_type7_shade(shade, xref, dict, funcs, func, stream); break;
default:
error = fz_throw("unknown shading type: %d", type);
goto cleanup;
}
if (stream)
fz_close(stream);
for (i = 0; i < funcs; i++)
if (func[i])
pdf_drop_function(func[i]);
*shadep = shade;
return fz_okay;
cleanup:
if (stream)
fz_close(stream);
for (i = 0; i < funcs; i++)
if (func[i])
pdf_drop_function(func[i]);
fz_drop_shade(shade);
return fz_rethrow(error, "cannot load shading type %d (%d %d R)", type, fz_to_num(dict), fz_to_gen(dict));
}
fz_error
pdf_load_shading(fz_shade **shadep, pdf_xref *xref, fz_obj *dict)
{
fz_error error;
fz_matrix mat;
fz_obj *obj;
if ((*shadep = pdf_find_item(xref->store, fz_drop_shade, dict)))
{
fz_keep_shade(*shadep);
return fz_okay;
}
/* Type 2 pattern dictionary */
if (fz_dict_gets(dict, "PatternType"))
{
obj = fz_dict_gets(dict, "Matrix");
if (obj)
mat = pdf_to_matrix(obj);
else
mat = fz_identity;
obj = fz_dict_gets(dict, "ExtGState");
if (obj)
{
if (fz_dict_gets(obj, "CA") || fz_dict_gets(obj, "ca"))
{
fz_warn("shading with alpha not supported");
}
}
obj = fz_dict_gets(dict, "Shading");
if (!obj)
return fz_throw("syntaxerror: missing shading dictionary");
error = pdf_load_shading_dict(shadep, xref, obj, mat);
if (error)
return fz_rethrow(error, "cannot load shading dictionary (%d %d R)", fz_to_num(obj), fz_to_gen(obj));
}
/* Naked shading dictionary */
else
{
error = pdf_load_shading_dict(shadep, xref, dict, fz_identity);
if (error)
return fz_rethrow(error, "cannot load shading dictionary (%d %d R)", fz_to_num(dict), fz_to_gen(dict));
}
pdf_store_item(xref->store, fz_keep_shade, fz_drop_shade, dict, *shadep);
return fz_okay;
}