eBookReaderSwitch/mupdf/source/fitz/list-device.c

#include "mupdf/fitz.h"

#include <assert.h>
#include <string.h>

typedef struct fz_display_node_s fz_display_node;
typedef struct fz_list_device_s fz_list_device;

#define STACK_SIZE 96

typedef enum fz_display_command_e
{
	FZ_CMD_FILL_PATH,
	FZ_CMD_STROKE_PATH,
	FZ_CMD_CLIP_PATH,
	FZ_CMD_CLIP_STROKE_PATH,
	FZ_CMD_FILL_TEXT,
	FZ_CMD_STROKE_TEXT,
	FZ_CMD_CLIP_TEXT,
	FZ_CMD_CLIP_STROKE_TEXT,
	FZ_CMD_IGNORE_TEXT,
	FZ_CMD_FILL_SHADE,
	FZ_CMD_FILL_IMAGE,
	FZ_CMD_FILL_IMAGE_MASK,
	FZ_CMD_CLIP_IMAGE_MASK,
	FZ_CMD_POP_CLIP,
	FZ_CMD_BEGIN_MASK,
	FZ_CMD_END_MASK,
	FZ_CMD_BEGIN_GROUP,
	FZ_CMD_END_GROUP,
	FZ_CMD_BEGIN_TILE,
	FZ_CMD_END_TILE,
	FZ_CMD_RENDER_FLAGS,
	FZ_CMD_DEFAULT_COLORSPACES,
	FZ_CMD_BEGIN_LAYER,
	FZ_CMD_END_LAYER
} fz_display_command;

/* The display list is a list of nodes.
 * Each node is a structure consisting of a bitfield (that packs into a
 * 32 bit word).
 * The different fields in the bitfield identify what information is
 * present in the node.
 *
 *	cmd:	What type of node this is.
 *
 *	size:	The number of sizeof(fz_display_node) bytes that this node's
 *		data occupies. (i.e. &node[node->size] = the next node in the
 *		chain; 0 for end of list).
 *
 *	rect:	0 for unchanged, 1 for present.
 *
 *	path:	0 for unchanged, 1 for present.
 *
 *	cs:	0 for unchanged
 *		1 for devicegray (color defaults to 0)
 *		2 for devicegray (color defaults to 1)
 *		3 for devicergb (color defaults to 0,0,0)
 *		4 for devicergb (color defaults to 1,1,1)
 *		5 for devicecmyk (color defaults to 0,0,0,0)
 *		6 for devicecmyk (color defaults to 0,0,0,1)
 *		7 for present (color defaults to 0)
 *
 *	color:	0 for unchanged color, 1 for present.
 *
 *	alpha:	0 for unchanged, 1 for solid, 2 for transparent, 3
 *		for alpha value present.
 *
 *	ctm:	0 for unchanged,
 *		1 for change ad
 *		2 for change bc
 *		4 for change ef.
 *
 *	stroke:	0 for unchanged, 1 for present.
 *
 *	flags:	Flags (node specific meanings)
 *
 * Nodes are packed in the order:
 * header, rect, colorspace, color, alpha, ctm, stroke_state, path, private data.
 */
struct fz_display_node_s
{
	unsigned int cmd    : 5;
	unsigned int size   : 9;
	unsigned int rect   : 1;
	unsigned int path   : 1;
	unsigned int cs     : 3;
	unsigned int color  : 1;
	unsigned int alpha  : 2;
	unsigned int ctm    : 3;
	unsigned int stroke : 1;
	unsigned int flags  : 6;
};

enum {
	CS_UNCHANGED = 0,
	CS_GRAY_0    = 1,
	CS_GRAY_1    = 2,
	CS_RGB_0     = 3,
	CS_RGB_1     = 4,
	CS_CMYK_0    = 5,
	CS_CMYK_1    = 6,
	CS_OTHER_0   = 7,

	ALPHA_UNCHANGED = 0,
	ALPHA_1         = 1,
	ALPHA_0         = 2,
	ALPHA_PRESENT   = 3,

	CTM_UNCHANGED = 0,
	CTM_CHANGE_AD = 1,
	CTM_CHANGE_BC = 2,
	CTM_CHANGE_EF = 4,

	MAX_NODE_SIZE = (1<<9)-sizeof(fz_display_node)
};

struct fz_display_list_s
{
	fz_storable storable;
	fz_display_node *list;
	fz_rect mediabox;
	size_t max;
	size_t len;
};

struct fz_list_device_s
{
	fz_device super;

	fz_display_list *list;

	fz_path *path;
	float alpha;
	fz_matrix ctm;
	fz_stroke_state *stroke;
	fz_colorspace *colorspace;
	fz_color_params *color_params;
	float color[FZ_MAX_COLORS];
	fz_rect rect;

	int top;
	struct {
		fz_rect *update;
		fz_rect rect;
	} stack[STACK_SIZE];
	int tiled;
};

enum { ISOLATED = 1, KNOCKOUT = 2 };
enum { OPM = 1, OP = 2, BP = 3, RI = 4};

#define SIZE_IN_NODES(t) \
	((t + sizeof(fz_display_node) - 1) / sizeof(fz_display_node))

static void
fz_append_display_node(
	fz_context *ctx,
	fz_device *dev,
	fz_display_command cmd,
	int flags,
	const fz_rect *rect,
	const fz_path *path,
	const float *color,
	fz_colorspace *colorspace,
	const float *alpha,
	const fz_matrix *ctm,
	const fz_stroke_state *stroke,
	const void *private_data,
	int private_data_len)
{
	fz_display_node node = { 0 };
	fz_display_node *node_ptr;
	fz_list_device *writer = (fz_list_device *)dev;
	fz_display_list *list = writer->list;
	int size;
	int rect_off = 0;
	int path_off = 0;
	int color_off = 0;
	int colorspace_off = 0;
	int alpha_off = 0;
	int ctm_off = 0;
	int stroke_off = 0;
	int rect_for_updates = 0;
	int private_off = 0;
	fz_path *my_path = NULL;
	fz_stroke_state *my_stroke = NULL;
	fz_rect local_rect;
	int path_size = 0;

	switch (cmd)
	{
	case FZ_CMD_CLIP_PATH:
	case FZ_CMD_CLIP_STROKE_PATH:
	case FZ_CMD_CLIP_TEXT:
	case FZ_CMD_CLIP_STROKE_TEXT:
	case FZ_CMD_CLIP_IMAGE_MASK:
		if (writer->top < STACK_SIZE)
		{
			rect_for_updates = 1;
			writer->stack[writer->top].rect = fz_empty_rect;
		}
		writer->top++;
		break;
	case FZ_CMD_END_MASK:
		if (writer->top < STACK_SIZE)
		{
			writer->stack[writer->top].update = NULL;
			writer->stack[writer->top].rect = fz_empty_rect;
		}
		writer->top++;
		break;
	case FZ_CMD_BEGIN_TILE:
		writer->tiled++;
		if (writer->top > 0 && writer->top <= STACK_SIZE)
		{
			writer->stack[writer->top-1].rect = fz_infinite_rect;
		}
		break;
	case FZ_CMD_END_TILE:
		writer->tiled--;
		break;
	case FZ_CMD_END_GROUP:
		break;
	case FZ_CMD_POP_CLIP:
		if (writer->top > STACK_SIZE)
		{
			writer->top--;
			rect = &fz_infinite_rect;
		}
		else if (writer->top > 0)
		{
			fz_rect *update;
			writer->top--;
			update = writer->stack[writer->top].update;
			if (writer->tiled == 0)
			{
				if (update)
				{
					*update = fz_intersect_rect(*update, writer->stack[writer->top].rect);
					local_rect = *update;
					rect = &local_rect;
				}
				else
					rect = &writer->stack[writer->top].rect;
			}
			else
				rect = &fz_infinite_rect;
		}
		/* fallthrough */
	default:
		if (writer->top > 0 && writer->tiled == 0 && writer->top <= STACK_SIZE && rect)
			writer->stack[writer->top-1].rect = fz_union_rect(writer->stack[writer->top-1].rect, *rect);
		break;
	}

	size = 1; /* 1 for the fz_display_node */
	node.cmd = cmd;

	/* Figure out what we need to write, and the offsets at which we will
	 * write it. */
	if (rect_for_updates || (rect != NULL && (writer->rect.x0 != rect->x0 || writer->rect.y0 != rect->y0 || writer->rect.x1 != rect->x1 || writer->rect.y1 != rect->y1)))
	{
		node.rect = 1;
		rect_off = size;
		size += SIZE_IN_NODES(sizeof(fz_rect));
	}
	if (color || colorspace)
	{
		if (colorspace != writer->colorspace)
		{
			assert(color);
			if (colorspace == fz_device_gray(ctx))
			{
				if (color[0] == 0.0f)
					node.cs = CS_GRAY_0, color = NULL;
				else
				{
					node.cs = CS_GRAY_1;
					if (color[0] == 1.0f)
						color = NULL;
				}
			}
			else if (colorspace == fz_device_rgb(ctx))
			{
				if (color[0] == 0.0f && color[1] == 0.0f && color[2] == 0.0f)
					node.cs = CS_RGB_0, color = NULL;
				else
				{
					node.cs = CS_RGB_1;
					if (color[0] == 1.0f && color[1] == 1.0f && color[2] == 1.0f)
						color = NULL;
				}
			}
			else if (colorspace == fz_device_cmyk(ctx))
			{
				node.cs = CS_CMYK_0;
				if (color[0] == 0.0f && color[1] == 0.0f && color[2] == 0.0f)
				{
					if (color[3] == 0.0f)
						color = NULL;
					else
					{
						node.cs = CS_CMYK_1;
						if (color[3] == 1.0f)
							color = NULL;
					}
				}
			}
			else
			{
				int i;
				int n = fz_colorspace_n(ctx, colorspace);

				colorspace_off = size;
				size += SIZE_IN_NODES(sizeof(fz_colorspace *));
				node.cs = CS_OTHER_0;
				for (i = 0; i < n; i++)
					if (color[i] != 0.0f)
						break;
				if (i == n)
					color = NULL;
				memset(writer->color, 0, sizeof(float)*n);
			}
		}
		else
		{
			/* Colorspace is unchanged, but color may have changed
			 * to something best coded as a colorspace change */
			if (colorspace == fz_device_gray(ctx))
			{
				if (writer->color[0] != color[0])
				{
					if (color[0] == 0.0f)
					{
						node.cs = CS_GRAY_0;
						color = NULL;
					}
					else if (color[0] == 1.0f)
					{
						node.cs = CS_GRAY_1;
						color = NULL;
					}
				}
			}
			else if (colorspace == fz_device_rgb(ctx))
			{
				if (writer->color[0] != color[0] || writer->color[1] != color[1] || writer->color[2] != color[2])
				{
					if (color[0] == 0.0f && color[1] == 0.0f && color[2] == 0.0f)
					{
						node.cs = CS_RGB_0;
						color = NULL;
					}
					else if (color[0] == 1.0f && color[1] == 1.0f && color[2] == 1.0f)
					{
						node.cs = CS_RGB_1;
						color = NULL;
					}
				}
			}
			else if (colorspace == fz_device_cmyk(ctx))
			{
				if (writer->color[0] != color[0] || writer->color[1] != color[1] || writer->color[2] != color[2] || writer->color[3] != color[3])
				{
					if (color[0] == 0.0f && color[1] == 0.0f && color[2] == 0.0f)
					{
						if (color[3] == 0.0f)
						{
							node.cs = CS_CMYK_0;
							color = NULL;
						}
						else if (color[3] == 1.0f)
						{
							node.cs = CS_CMYK_1;
							color = NULL;
						}
					}
				}
			}
			else
			{
				int i;
				int n = fz_colorspace_n(ctx, colorspace);
				for (i=0; i < n; i++)
					if (color[i] != 0.0f)
						break;
				if (i == n)
				{
					node.cs = CS_OTHER_0;
					colorspace_off = size;
					size += SIZE_IN_NODES(sizeof(fz_colorspace *));
					color = NULL;
				}
			}
		}
	}
	if (color)
	{
		int i, n;
		const float *wc = &writer->color[0];

		assert(colorspace != NULL);
		n = fz_colorspace_n(ctx, colorspace);
		i = 0;
		/* Only check colors if the colorspace is unchanged. If the
		 * colorspace *has* changed and the colors are implicit then
		 * this will have been caught above. */
		if (colorspace == writer->colorspace)
			for (; i < n; i++)
				if (color[i] != wc[i])
					break;

		if (i != n)
		{
			node.color = 1;
			color_off = size;
			size += n * SIZE_IN_NODES(sizeof(float));
		}
	}
	if (alpha && (*alpha != writer->alpha))
	{
		if (*alpha >= 1.0f)
			node.alpha = ALPHA_1;
		else if (*alpha <= 0.0f)
			node.alpha = ALPHA_0;
		else
		{
			alpha_off = size;
			size += SIZE_IN_NODES(sizeof(float));
			node.alpha = ALPHA_PRESENT;
		}
	}
	if (ctm && (ctm->a != writer->ctm.a || ctm->b != writer->ctm.b || ctm->c != writer->ctm.c || ctm->d != writer->ctm.d || ctm->e != writer->ctm.e || ctm->f != writer->ctm.f))
	{
		int ctm_flags;

		ctm_off = size;
		ctm_flags = CTM_UNCHANGED;
		if (ctm->a != writer->ctm.a || ctm->d != writer->ctm.d)
			ctm_flags = CTM_CHANGE_AD, size += SIZE_IN_NODES(2*sizeof(float));
		if (ctm->b != writer->ctm.b || ctm->c != writer->ctm.c)
			ctm_flags |= CTM_CHANGE_BC, size += SIZE_IN_NODES(2*sizeof(float));
		if (ctm->e != writer->ctm.e || ctm->f != writer->ctm.f)
			ctm_flags |= CTM_CHANGE_EF, size += SIZE_IN_NODES(2*sizeof(float));
		node.ctm = ctm_flags;
	}
	if (stroke && (writer->stroke == NULL || stroke != writer->stroke))
	{
		stroke_off = size;
		size += SIZE_IN_NODES(sizeof(fz_stroke_state *));
		node.stroke = 1;
	}
	if (path && (writer->path == NULL || path != writer->path))
	{
		size_t max = SIZE_IN_NODES(MAX_NODE_SIZE) - size - SIZE_IN_NODES(private_data_len);
		path_size = SIZE_IN_NODES(fz_pack_path(ctx, NULL, max, path));
		node.path = 1;
		path_off = size;

		size += path_size;
	}
	if (private_data != NULL)
	{
		size_t max = SIZE_IN_NODES(MAX_NODE_SIZE) - size;
		if (SIZE_IN_NODES(private_data_len) > max)
			fz_throw(ctx, FZ_ERROR_GENERIC, "Private data too large to pack into display list node");
		private_off = size;
		size += SIZE_IN_NODES(private_data_len);
	}

	while (list->len + size > list->max)
	{
		size_t newsize = list->max * 2;
		fz_display_node *old = list->list;
		ptrdiff_t diff;
		int i, n;

		if (newsize < 256)
			newsize = 256;
		list->list = fz_realloc_array(ctx, list->list, newsize, fz_display_node);
		list->max = newsize;
		diff = (char *)(list->list) - (char *)old;
		n = (writer->top < STACK_SIZE ? writer->top : STACK_SIZE);
		for (i = 0; i < n; i++)
		{
			if (writer->stack[i].update != NULL)
				writer->stack[i].update = (fz_rect *)(((char *)writer->stack[i].update) + diff);
		}
		if (writer->path)
			writer->path = (fz_path *)(((char *)writer->path) + diff);
	}

	/* Write the node to the list */
	node.size = size;
	node.flags = flags;
	assert(size < (1<<9));
	node_ptr = &list->list[list->len];
	*node_ptr = node;

	/* Path is the most frequent one, so try to avoid the try/catch in
	 * this case */
	if (path_off)
	{
		my_path = (void *)(&node_ptr[path_off]);
		(void)fz_pack_path(ctx, (void *)my_path, path_size * sizeof(fz_display_node), path);
	}

	if (stroke_off)
	{
		fz_try(ctx)
		{
			my_stroke = fz_keep_stroke_state(ctx, stroke);
		}
		fz_catch(ctx)
		{
			fz_drop_path(ctx, my_path);
			fz_rethrow(ctx);
		}
	}

	if (rect_off)
	{
		fz_rect *out_rect = (fz_rect *)(void *)(&node_ptr[rect_off]);
		writer->rect = *rect;
		*out_rect = *rect;
		if (rect_for_updates)
			writer->stack[writer->top-1].update = out_rect;
	}
	if (path_off)
	{
		fz_drop_path(ctx, writer->path);
		writer->path = fz_keep_path(ctx, my_path); /* Can never fail */
	}
	if (node.cs)
	{
		fz_drop_colorspace(ctx, writer->colorspace);
		switch(node.cs)
		{
		case CS_GRAY_0:
			writer->colorspace = fz_keep_colorspace(ctx, fz_device_gray(ctx));
			writer->color[0] = 0;
			break;
		case CS_GRAY_1:
			writer->colorspace = fz_keep_colorspace(ctx, fz_device_gray(ctx));
			writer->color[0] = 1;
			break;
		case CS_RGB_0:
			writer->color[0] = 0;
			writer->color[1] = 0;
			writer->color[2] = 0;
			writer->colorspace = fz_keep_colorspace(ctx, fz_device_rgb(ctx));
			break;
		case CS_RGB_1:
			writer->color[0] = 1;
			writer->color[1] = 1;
			writer->color[2] = 1;
			writer->colorspace = fz_keep_colorspace(ctx, fz_device_rgb(ctx));
			break;
		case CS_CMYK_0:
			writer->color[0] = 0;
			writer->color[1] = 0;
			writer->color[2] = 0;
			writer->color[3] = 0;
			writer->colorspace = fz_keep_colorspace(ctx, fz_device_cmyk(ctx));
			break;
		case CS_CMYK_1:
			writer->color[0] = 0;
			writer->color[1] = 0;
			writer->color[2] = 0;
			writer->color[3] = 1;
			writer->colorspace = fz_keep_colorspace(ctx, fz_device_cmyk(ctx));
			break;
		default:
		{
			fz_colorspace **out_colorspace = (fz_colorspace **)(void *)(&node_ptr[colorspace_off]);
			int i, n;
			n = fz_colorspace_n(ctx, colorspace);
			*out_colorspace = fz_keep_colorspace(ctx, colorspace);

			writer->colorspace = fz_keep_colorspace(ctx, colorspace);
			for (i = 0; i < n; i++)
				writer->color[i] = 0;
			break;
		}
		}
	}
	if (color_off)
	{
		int n = fz_colorspace_n(ctx, colorspace);
		float *out_color = (float *)(void *)(&node_ptr[color_off]);
		memcpy(writer->color, color, n * sizeof(float));
		memcpy(out_color, color, n * sizeof(float));
	}
	if (node.alpha)
	{
		writer->alpha = *alpha;
		if (alpha_off)
		{
			float *out_alpha = (float *)(void *)(&node_ptr[alpha_off]);
			*out_alpha = *alpha;
		}
	}
	if (ctm_off)
	{
		float *out_ctm = (float *)(void *)(&node_ptr[ctm_off]);
		if (node.ctm & CTM_CHANGE_AD)
		{
			writer->ctm.a = *out_ctm++ = ctm->a;
			writer->ctm.d = *out_ctm++ = ctm->d;
		}
		if (node.ctm & CTM_CHANGE_BC)
		{
			writer->ctm.b = *out_ctm++ = ctm->b;
			writer->ctm.c = *out_ctm++ = ctm->c;
		}
		if (node.ctm & CTM_CHANGE_EF)
		{
			writer->ctm.e = *out_ctm++ = ctm->e;
			writer->ctm.f = *out_ctm = ctm->f;
		}
	}
	if (stroke_off)
	{
		fz_stroke_state **out_stroke = (fz_stroke_state **)(void *)(&node_ptr[stroke_off]);
		*out_stroke = my_stroke;
		fz_drop_stroke_state(ctx, writer->stroke);
		/* Can never fail as my_stroke was kept above */
		writer->stroke = fz_keep_stroke_state(ctx, my_stroke);
	}
	if (private_off)
	{
		char *out_private = (char *)(void *)(&node_ptr[private_off]);
		memcpy(out_private, private_data, private_data_len);
	}
	list->len += size;
}

/* Pack ri, op, opm, bp into flags upper bits, even/odd in lower bit */
static int
fz_pack_color_params(fz_color_params color_params)
{
	int flags = 0;
	flags |= color_params.ri << RI; /* 2 bits */
	flags |= color_params.bp << BP;
	flags |= color_params.op << OP;
	flags |= color_params.opm << OPM;
	return flags;
}

/* unpack ri, op, opm, bp from flags, even/odd in lower bit */
static void
fz_unpack_color_params(fz_color_params *color_params, int flags)
{
	color_params->ri = (flags >> RI) & 3;
	color_params->bp = (flags >> BP) & 1;
	color_params->op = (flags >> OP) & 1;
	color_params->opm = (flags >> OPM) & 1;
}

static void
fz_list_fill_path(fz_context *ctx, fz_device *dev, const fz_path *path, int even_odd, fz_matrix ctm,
	fz_colorspace *colorspace, const float *color, float alpha, fz_color_params color_params)
{
	fz_rect rect = fz_bound_path(ctx, path, NULL, ctm);
	fz_append_display_node(
		ctx,
		dev,
		FZ_CMD_FILL_PATH,
		even_odd | fz_pack_color_params(color_params), /* flags */
		&rect,
		path, /* path */
		color,
		colorspace,
		&alpha, /* alpha */
		&ctm,
		NULL, /* stroke_state */
		NULL, /* private_data */
		0); /* private_data_len */
}

static void
fz_list_stroke_path(fz_context *ctx, fz_device *dev, const fz_path *path, const fz_stroke_state *stroke,
	fz_matrix ctm, fz_colorspace *colorspace, const float *color, float alpha, fz_color_params color_params)
{
	fz_rect rect = fz_bound_path(ctx, path, stroke, ctm);
	fz_append_display_node(
		ctx,
		dev,
		FZ_CMD_STROKE_PATH,
		fz_pack_color_params(color_params), /* flags */
		&rect,
		path, /* path */
		color,
		colorspace,
		&alpha, /* alpha */
		&ctm, /* ctm */
		stroke,
		NULL, /* private_data */
		0); /* private_data_len */
}

static void
fz_list_clip_path(fz_context *ctx, fz_device *dev, const fz_path *path, int even_odd, fz_matrix ctm, fz_rect scissor)
{
	fz_rect rect = fz_bound_path(ctx, path, NULL, ctm);
	rect = fz_intersect_rect(rect, scissor);
	fz_append_display_node(
		ctx,
		dev,
		FZ_CMD_CLIP_PATH,
		even_odd, /* flags */
		&rect,
		path, /* path */
		NULL, /* color */
		NULL, /* colorspace */
		NULL, /* alpha */
		&ctm, /* ctm */
		NULL, /* stroke */
		NULL, /* private_data */
		0); /* private_data_len */
}

static void
fz_list_clip_stroke_path(fz_context *ctx, fz_device *dev, const fz_path *path, const fz_stroke_state *stroke, fz_matrix ctm, fz_rect scissor)
{
	fz_rect rect = fz_bound_path(ctx, path, stroke, ctm);
	rect = fz_intersect_rect(rect, scissor);
	fz_append_display_node(
		ctx,
		dev,
		FZ_CMD_CLIP_STROKE_PATH,
		0, /* flags */
		&rect,
		path, /* path */
		NULL, /* color */
		NULL, /* colorspace */
		NULL, /* alpha */
		&ctm, /* ctm */
		stroke, /* stroke */
		NULL, /* private_data */
		0); /* private_data_len */
}

static void
fz_list_fill_text(fz_context *ctx, fz_device *dev, const fz_text *text, fz_matrix ctm,
	fz_colorspace *colorspace, const float *color, float alpha, fz_color_params color_params)
{
	fz_text *cloned_text = fz_keep_text(ctx, text);
	fz_try(ctx)
	{
		fz_rect rect = fz_bound_text(ctx, text, NULL, ctm);
		fz_append_display_node(
			ctx,
			dev,
			FZ_CMD_FILL_TEXT,
			fz_pack_color_params(color_params), /* flags */
			&rect,
			NULL, /* path */
			color, /* color */
			colorspace, /* colorspace */
			&alpha, /* alpha */
			&ctm, /* ctm */
			NULL, /* stroke */
			&cloned_text, /* private_data */
			sizeof(cloned_text)); /* private_data_len */
	}
	fz_catch(ctx)
	{
		fz_drop_text(ctx, cloned_text);
		fz_rethrow(ctx);
	}
}

static void
fz_list_stroke_text(fz_context *ctx, fz_device *dev, const fz_text *text, const fz_stroke_state *stroke, fz_matrix ctm,
	fz_colorspace *colorspace, const float *color, float alpha, fz_color_params color_params)
{
	fz_text *cloned_text = fz_keep_text(ctx, text);
	fz_try(ctx)
	{
		fz_rect rect = fz_bound_text(ctx, text, stroke, ctm);
		fz_append_display_node(
			ctx,
			dev,
			FZ_CMD_STROKE_TEXT,
			fz_pack_color_params(color_params), /* flags */
			&rect,
			NULL, /* path */
			color, /* color */
			colorspace, /* colorspace */
			&alpha, /* alpha */
			&ctm, /* ctm */
			stroke,
			&cloned_text, /* private_data */
			sizeof(cloned_text)); /* private_data_len */
	}
	fz_catch(ctx)
	{
		fz_drop_text(ctx, cloned_text);
		fz_rethrow(ctx);
	}
}

static void
fz_list_clip_text(fz_context *ctx, fz_device *dev, const fz_text *text, fz_matrix ctm, fz_rect scissor)
{
	fz_text *cloned_text = fz_keep_text(ctx, text);
	fz_try(ctx)
	{
		fz_rect rect = fz_bound_text(ctx, text, NULL, ctm);
		rect = fz_intersect_rect(rect, scissor);
		fz_append_display_node(
			ctx,
			dev,
			FZ_CMD_CLIP_TEXT,
			0, /* flags */
			&rect,
			NULL, /* path */
			NULL, /* color */
			NULL, /* colorspace */
			NULL, /* alpha */
			&ctm, /* ctm */
			NULL, /* stroke */
			&cloned_text, /* private_data */
			sizeof(cloned_text)); /* private_data_len */
	}
	fz_catch(ctx)
	{
		fz_drop_text(ctx, cloned_text);
		fz_rethrow(ctx);
	}
}

static void
fz_list_clip_stroke_text(fz_context *ctx, fz_device *dev, const fz_text *text, const fz_stroke_state *stroke, fz_matrix ctm, fz_rect scissor)
{
	fz_text *cloned_text = fz_keep_text(ctx, text);
	fz_try(ctx)
	{
		fz_rect rect = fz_bound_text(ctx, text, stroke, ctm);
		rect = fz_intersect_rect(rect, scissor);
		fz_append_display_node(
			ctx,
			dev,
			FZ_CMD_CLIP_STROKE_TEXT,
			0, /* flags */
			&rect,
			NULL, /* path */
			NULL, /* color */
			NULL, /* colorspace */
			NULL, /* alpha */
			&ctm, /* ctm */
			stroke, /* stroke */
			&cloned_text, /* private_data */
			sizeof(cloned_text)); /* private_data_len */
	}
	fz_catch(ctx)
	{
		fz_drop_text(ctx, cloned_text);
		fz_rethrow(ctx);
	}
}

static void
fz_list_ignore_text(fz_context *ctx, fz_device *dev, const fz_text *text, fz_matrix ctm)
{
	fz_text *cloned_text = fz_keep_text(ctx, text);
	fz_try(ctx)
	{
		fz_rect rect = fz_bound_text(ctx, text, NULL, ctm);
		fz_append_display_node(
			ctx,
			dev,
			FZ_CMD_IGNORE_TEXT,
			0, /* flags */
			&rect,
			NULL, /* path */
			NULL, /* color */
			NULL, /* colorspace */
			NULL, /* alpha */
			&ctm, /* ctm */
			NULL, /* stroke */
			&cloned_text, /* private_data */
			sizeof(cloned_text)); /* private_data_len */
	}
	fz_catch(ctx)
	{
		fz_drop_text(ctx, cloned_text);
		fz_rethrow(ctx);
	}
}

static void
fz_list_pop_clip(fz_context *ctx, fz_device *dev)
{
	fz_append_display_node(
		ctx,
		dev,
		FZ_CMD_POP_CLIP,
		0, /* flags */
		NULL, /* rect */
		NULL, /* path */
		NULL, /* color */
		NULL, /* colorspace */
		NULL, /* alpha */
		NULL, /* ctm */
		NULL, /* stroke */
		NULL, /* private_data */
		0); /* private_data_len */
}

static void
fz_list_fill_shade(fz_context *ctx, fz_device *dev, fz_shade *shade, fz_matrix ctm, float alpha, fz_color_params color_params)
{
	fz_shade *shade2 = fz_keep_shade(ctx, shade);
	fz_try(ctx)
	{
		fz_rect rect = fz_bound_shade(ctx, shade, ctm);
		fz_append_display_node(
			ctx,
			dev,
			FZ_CMD_FILL_SHADE,
			fz_pack_color_params(color_params), /* flags */
			&rect,
			NULL, /* path */
			NULL, /* color */
			NULL, /* colorspace */
			&alpha, /* alpha */
			&ctm, /* ctm */
			NULL, /* stroke */
			&shade2, /* private_data */
			sizeof(shade2)); /* private_data_len */
	}
	fz_catch(ctx)
	{
		fz_drop_shade(ctx, shade2);
		fz_rethrow(ctx);
	}
}

static void
fz_list_fill_image(fz_context *ctx, fz_device *dev, fz_image *image, fz_matrix ctm, float alpha, fz_color_params color_params)
{
	fz_image *image2 = fz_keep_image(ctx, image);
	fz_try(ctx)
	{
		fz_rect rect = fz_transform_rect(fz_unit_rect, ctm);
		fz_append_display_node(
			ctx,
			dev,
			FZ_CMD_FILL_IMAGE,
			fz_pack_color_params(color_params), /* flags */
			&rect,
			NULL, /* path */
			NULL, /* color */
			NULL, /* colorspace */
			&alpha, /* alpha */
			&ctm, /* ctm */
			NULL, /* stroke */
			&image2, /* private_data */
			sizeof(image2)); /* private_data_len */
	}
	fz_catch(ctx)
	{
		fz_drop_image(ctx, image2);
		fz_rethrow(ctx);
	}
}

static void
fz_list_fill_image_mask(fz_context *ctx, fz_device *dev, fz_image *image, fz_matrix ctm,
	fz_colorspace *colorspace, const float *color, float alpha, fz_color_params color_params)
{
	fz_image *image2 = fz_keep_image(ctx, image);

	fz_try(ctx)
	{
		fz_rect rect = fz_transform_rect(fz_unit_rect, ctm);
		fz_append_display_node(
			ctx,
			dev,
			FZ_CMD_FILL_IMAGE_MASK,
			fz_pack_color_params(color_params), /* flags */
			&rect,
			NULL, /* path */
			color,
			colorspace,
			&alpha, /* alpha */
			&ctm, /* ctm */
			NULL, /* stroke */
			&image2, /* private_data */
			sizeof(image2)); /* private_data_len */
	}
	fz_catch(ctx)
	{
		fz_drop_image(ctx, image2);
		fz_rethrow(ctx);
	}
}

static void
fz_list_clip_image_mask(fz_context *ctx, fz_device *dev, fz_image *image, fz_matrix ctm, fz_rect scissor)
{
	fz_image *image2 = fz_keep_image(ctx, image);
	fz_try(ctx)
	{
		fz_rect rect = fz_transform_rect(fz_unit_rect, ctm);
		rect = fz_intersect_rect(rect, scissor);
		fz_append_display_node(
			ctx,
			dev,
			FZ_CMD_CLIP_IMAGE_MASK,
			0, /* flags */
			&rect,
			NULL, /* path */
			NULL, /* color */
			NULL, /* colorspace */
			NULL, /* alpha */
			&ctm, /* ctm */
			NULL, /* stroke */
			&image2, /* private_data */
			sizeof(image2)); /* private_data_len */
	}
	fz_catch(ctx)
	{
		fz_drop_image(ctx, image2);
		fz_rethrow(ctx);
	}
}

static void
fz_list_begin_mask(fz_context *ctx, fz_device *dev, fz_rect rect, int luminosity, fz_colorspace *colorspace, const float *color, fz_color_params color_params)
{
	fz_append_display_node(
		ctx,
		dev,
		FZ_CMD_BEGIN_MASK,
		(!!luminosity) | fz_pack_color_params(color_params), /* flags */
		&rect,
		NULL, /* path */
		color,
		colorspace,
		NULL, /* alpha */
		NULL, /* ctm */
		NULL, /* stroke */
		NULL, /* private_data */
		0); /* private_data_len */
}

static void
fz_list_end_mask(fz_context *ctx, fz_device *dev)
{
	fz_append_display_node(
		ctx,
		dev,
		FZ_CMD_END_MASK,
		0, /* flags */
		NULL, /* rect */
		NULL, /* path */
		NULL, /* color */
		NULL, /* colorspace */
		NULL, /* alpha */
		NULL, /* ctm */
		NULL, /* stroke */
		NULL, /* private_data */
		0); /* private_data_len */
}

static void
fz_list_begin_group(fz_context *ctx, fz_device *dev, fz_rect rect, fz_colorspace *colorspace, int isolated, int knockout, int blendmode, float alpha)
{
	int flags;

	colorspace = fz_keep_colorspace(ctx, colorspace);

	flags = (blendmode<<2);
	if (isolated)
		flags |= ISOLATED;
	if (knockout)
		flags |= KNOCKOUT;

	fz_try(ctx)
	{
		fz_append_display_node(
			ctx,
			dev,
			FZ_CMD_BEGIN_GROUP,
			flags,
			&rect,
			NULL, /* path */
			NULL, /* color */
			NULL, /* colorspace */
			&alpha, /* alpha */
			NULL, /* ctm */
			NULL, /* stroke */
			&colorspace, /* private_data */
			sizeof(colorspace)); /* private_data_len */
	}
	fz_catch(ctx)
	{
		fz_drop_colorspace(ctx, colorspace);
		fz_rethrow(ctx);
	}
}

static void
fz_list_end_group(fz_context *ctx, fz_device *dev)
{
	fz_append_display_node(
		ctx,
		dev,
		FZ_CMD_END_GROUP,
		0, /* flags */
		NULL, /* rect */
		NULL, /* path */
		NULL, /* color */
		NULL, /* colorspace */
		NULL, /* alpha */
		NULL, /* ctm */
		NULL, /* stroke */
		NULL, /* private_data */
		0); /* private_data_len */
}

typedef struct fz_list_tile_data_s fz_list_tile_data;

struct fz_list_tile_data_s
{
	float xstep;
	float ystep;
	fz_rect view;
	int id;
};

static int
fz_list_begin_tile(fz_context *ctx, fz_device *dev, fz_rect area, fz_rect view, float xstep, float ystep, fz_matrix ctm, int id)
{
	fz_list_tile_data tile;

	tile.xstep = xstep;
	tile.ystep = ystep;
	tile.view = view;
	tile.id = id;
	fz_append_display_node(
		ctx,
		dev,
		FZ_CMD_BEGIN_TILE,
		0, /* flags */
		&area,
		NULL, /* path */
		NULL, /* color */
		NULL, /* colorspace */
		NULL, /* alpha */
		&ctm, /* ctm */
		NULL, /* stroke */
		&tile, /* private_data */
		sizeof(tile)); /* private_data_len */

	return 0;
}

static void
fz_list_end_tile(fz_context *ctx, fz_device *dev)
{
	fz_append_display_node(
		ctx,
		dev,
		FZ_CMD_END_TILE,
		0, /* flags */
		NULL,
		NULL, /* path */
		NULL, /* color */
		NULL, /* colorspace */
		NULL, /* alpha */
		NULL, /* ctm */
		NULL, /* stroke */
		NULL, /* private_data */
		0); /* private_data_len */
}

static void
fz_list_render_flags(fz_context *ctx, fz_device *dev, int set, int clear)
{
	int flags;

	/* Pack the options down */
	if (set == FZ_DEVFLAG_GRIDFIT_AS_TILED && clear == 0)
		flags = 1;
	else if (set == 0 && clear == FZ_DEVFLAG_GRIDFIT_AS_TILED)
		flags = 0;
	else
	{
		assert("Unsupported flags combination" == NULL);
		return;
	}
	fz_append_display_node(
		ctx,
		dev,
		FZ_CMD_RENDER_FLAGS,
		flags, /* flags */
		NULL,
		NULL, /* path */
		NULL, /* color */
		NULL, /* colorspace */
		NULL, /* alpha */
		NULL, /* ctm */
		NULL, /* stroke */
		NULL, /* private_data */
		0); /* private_data_len */
}

static void
fz_list_set_default_colorspaces(fz_context *ctx, fz_device *dev, fz_default_colorspaces *default_cs)
{
	fz_default_colorspaces *default_cs2 = fz_keep_default_colorspaces(ctx, default_cs);

	fz_try(ctx)
	{
		fz_append_display_node(
			ctx,
			dev,
			FZ_CMD_DEFAULT_COLORSPACES,
			0, /* flags */
			NULL,
			NULL, /* path */
			NULL, /* color */
			NULL, /* colorspace */
			NULL, /* alpha */
			NULL, /* ctm */
			NULL, /* stroke */
			&default_cs2, /* private_data */
			sizeof(default_cs2)); /* private_data_len */
	}
	fz_catch(ctx)
	{
		fz_drop_default_colorspaces(ctx, default_cs2);
		fz_rethrow(ctx);
	}
}

static void
fz_list_begin_layer(fz_context *ctx, fz_device *dev, const char *layer_name)
{
	fz_append_display_node(
		ctx,
		dev,
		FZ_CMD_BEGIN_LAYER,
		0, /* flags */
		NULL,
		NULL, /* path */
		NULL, /* color */
		NULL, /* colorspace */
		NULL, /* alpha */
		NULL,
		NULL, /* stroke */
		layer_name, /* private_data */
		1+strlen(layer_name)); /* private_data_len */
}

static void
fz_list_end_layer(fz_context *ctx, fz_device *dev)
{
	fz_append_display_node(
		ctx,
		dev,
		FZ_CMD_END_LAYER,
		0, /* flags */
		NULL,
		NULL, /* path */
		NULL, /* color */
		NULL, /* colorspace */
		NULL, /* alpha */
		NULL, /* ctm */
		NULL, /* stroke */
		NULL, /* private_data */
		0); /* private_data_len */
}

static void
fz_list_drop_device(fz_context *ctx, fz_device *dev)
{
	fz_list_device *writer = (fz_list_device *)dev;

	fz_drop_colorspace(ctx, writer->colorspace);
	fz_drop_stroke_state(ctx, writer->stroke);
	fz_drop_path(ctx, writer->path);
}

/*
	Create a rendering device for a display list.

	When the device is rendering a page it will populate the
	display list with drawing commands (text, images, etc.). The
	display list can later be reused to render a page many times
	without having to re-interpret the page from the document file
	for each rendering. Once the device is no longer needed, free
	it with fz_drop_device.

	list: A display list that the list device takes ownership of.
*/
fz_device *
fz_new_list_device(fz_context *ctx, fz_display_list *list)
{
	fz_list_device *dev;

	dev = fz_new_derived_device(ctx, fz_list_device);

	dev->super.fill_path = fz_list_fill_path;
	dev->super.stroke_path = fz_list_stroke_path;
	dev->super.clip_path = fz_list_clip_path;
	dev->super.clip_stroke_path = fz_list_clip_stroke_path;

	dev->super.fill_text = fz_list_fill_text;
	dev->super.stroke_text = fz_list_stroke_text;
	dev->super.clip_text = fz_list_clip_text;
	dev->super.clip_stroke_text = fz_list_clip_stroke_text;
	dev->super.ignore_text = fz_list_ignore_text;

	dev->super.fill_shade = fz_list_fill_shade;
	dev->super.fill_image = fz_list_fill_image;
	dev->super.fill_image_mask = fz_list_fill_image_mask;
	dev->super.clip_image_mask = fz_list_clip_image_mask;

	dev->super.pop_clip = fz_list_pop_clip;

	dev->super.begin_mask = fz_list_begin_mask;
	dev->super.end_mask = fz_list_end_mask;
	dev->super.begin_group = fz_list_begin_group;
	dev->super.end_group = fz_list_end_group;

	dev->super.begin_tile = fz_list_begin_tile;
	dev->super.end_tile = fz_list_end_tile;

	dev->super.render_flags = fz_list_render_flags;
	dev->super.set_default_colorspaces = fz_list_set_default_colorspaces;

	dev->super.begin_layer = fz_list_begin_layer;
	dev->super.end_layer = fz_list_end_layer;

	dev->super.drop_device = fz_list_drop_device;

	dev->list = list;
	dev->path = NULL;
	dev->alpha = 1.0f;
	dev->ctm = fz_identity;
	dev->stroke = NULL;
	dev->colorspace = fz_keep_colorspace(ctx, fz_device_gray(ctx));
	memset(dev->color, 0, sizeof(float)*FZ_MAX_COLORS);
	dev->top = 0;
	dev->tiled = 0;

	return &dev->super;
}

static void
fz_drop_display_list_imp(fz_context *ctx, fz_storable *list_)
{
	fz_display_list *list = (fz_display_list *)list_;
	fz_display_node *node = list->list;
	fz_display_node *node_end = list->list + list->len;
	int cs_n = 1;
	fz_colorspace *cs;

	while (node != node_end)
	{
		fz_display_node n = *node;
		fz_display_node *next = node + n.size;

		node++;
		if (n.rect)
		{
			node += SIZE_IN_NODES(sizeof(fz_rect));
		}
		switch (n.cs)
		{
		default:
		case CS_UNCHANGED:
			break;
		case CS_GRAY_0:
		case CS_GRAY_1:
			cs_n = 1;
			break;
		case CS_RGB_0:
		case CS_RGB_1:
			cs_n = 3;
			break;
		case CS_CMYK_0:
		case CS_CMYK_1:
			cs_n = 4;
			break;
		case CS_OTHER_0:
			cs = *(fz_colorspace **)node;
			cs_n = fz_colorspace_n(ctx, cs);
			fz_drop_colorspace(ctx, cs);
			node += SIZE_IN_NODES(sizeof(fz_colorspace *));
			break;
		}
		if (n.color)
		{
			node += SIZE_IN_NODES(cs_n * sizeof(float));
		}
		if (n.alpha == ALPHA_PRESENT)
		{
			node += SIZE_IN_NODES(sizeof(float));
		}
		if (n.ctm & CTM_CHANGE_AD)
			node += SIZE_IN_NODES(2*sizeof(float));
		if (n.ctm & CTM_CHANGE_BC)
			node += SIZE_IN_NODES(2*sizeof(float));
		if (n.ctm & CTM_CHANGE_EF)
			node += SIZE_IN_NODES(2*sizeof(float));
		if (n.stroke)
		{
			fz_drop_stroke_state(ctx, *(fz_stroke_state **)node);
			node += SIZE_IN_NODES(sizeof(fz_stroke_state *));
		}
		if (n.path)
		{
			int path_size = fz_packed_path_size((fz_path *)node);
			fz_drop_path(ctx, (fz_path *)node);
			node += SIZE_IN_NODES(path_size);
		}
		switch(n.cmd)
		{
		case FZ_CMD_FILL_TEXT:
		case FZ_CMD_STROKE_TEXT:
		case FZ_CMD_CLIP_TEXT:
		case FZ_CMD_CLIP_STROKE_TEXT:
		case FZ_CMD_IGNORE_TEXT:
			fz_drop_text(ctx, *(fz_text **)node);
			break;
		case FZ_CMD_FILL_SHADE:
			fz_drop_shade(ctx, *(fz_shade **)node);
			break;
		case FZ_CMD_FILL_IMAGE:
		case FZ_CMD_FILL_IMAGE_MASK:
		case FZ_CMD_CLIP_IMAGE_MASK:
			fz_drop_image(ctx, *(fz_image **)node);
			break;
		case FZ_CMD_BEGIN_GROUP:
			fz_drop_colorspace(ctx, *(fz_colorspace **)node);
			break;
		case FZ_CMD_DEFAULT_COLORSPACES:
			fz_drop_default_colorspaces(ctx, *(fz_default_colorspaces **)node);
			break;
		}
		node = next;
	}
	fz_free(ctx, list->list);
	fz_free(ctx, list);
}

/*
	Create an empty display list.

	A display list contains drawing commands (text, images, etc.).
	Use fz_new_list_device for populating the list.

	mediabox: Bounds of the page (in points) represented by the display list.
*/
fz_display_list *
fz_new_display_list(fz_context *ctx, fz_rect mediabox)
{
	fz_display_list *list = fz_malloc_struct(ctx, fz_display_list);
	FZ_INIT_STORABLE(list, 1, fz_drop_display_list_imp);
	list->list = NULL;
	list->mediabox = mediabox;
	list->max = 0;
	list->len = 0;
	return list;
}

fz_display_list *
fz_keep_display_list(fz_context *ctx, fz_display_list *list)
{
	return fz_keep_storable(ctx, &list->storable);
}

void
fz_drop_display_list(fz_context *ctx, fz_display_list *list)
{
	fz_defer_reap_start(ctx);
	fz_drop_storable(ctx, &list->storable);
	fz_defer_reap_end(ctx);
}

/*
	Return the bounding box of the page recorded in a display list.
*/
fz_rect
fz_bound_display_list(fz_context *ctx, fz_display_list *list)
{
	return list->mediabox;
}

/*
	Check for a display list being empty

	list: The list to check.

	Returns true if empty, false otherwise.
*/
int fz_display_list_is_empty(fz_context *ctx, const fz_display_list *list)
{
	return !list || list->len == 0;
}

/*
	(Re)-run a display list through a device.

	list: A display list, created by fz_new_display_list and
	populated with objects from a page by running fz_run_page on a
	device obtained from fz_new_list_device.

	ctm: Transform to apply to display list contents. May include
	for example scaling and rotation, see fz_scale, fz_rotate and
	fz_concat. Set to fz_identity if no transformation is desired.

	scissor: Only the part of the contents of the display list
	visible within this area will be considered when the list is
	run through the device. This does not imply for tile objects
	contained in the display list.

	cookie: Communication mechanism between caller and library
	running the page. Intended for multi-threaded applications,
	while single-threaded applications set cookie to NULL. The
	caller may abort an ongoing page run. Cookie also communicates
	progress information back to the caller. The fields inside
	cookie are continually updated while the page is being run.
*/
void
fz_run_display_list(fz_context *ctx, fz_display_list *list, fz_device *dev, fz_matrix top_ctm, fz_rect scissor, fz_cookie *cookie)
{
	fz_display_node *node;
	fz_display_node *node_end;
	fz_display_node *next_node;
	int clipped = 0;
	int tiled = 0;
	int progress = 0;

	/* Current graphics state as unpacked from list */
	fz_path *path = NULL;
	float alpha = 1.0f;
	fz_matrix ctm = fz_identity;
	fz_stroke_state *stroke = NULL;
	float color[FZ_MAX_COLORS] = { 0 };
	fz_colorspace *colorspace = fz_keep_colorspace(ctx, fz_device_gray(ctx));
	fz_color_params color_params;
	fz_rect rect = { 0 };

	/* Transformed versions of graphic state entries */
	fz_rect trans_rect;
	fz_matrix trans_ctm;
	int tile_skip_depth = 0;

	if (cookie)
	{
		cookie->progress_max = list->len;
		cookie->progress = 0;
	}

	color_params = fz_default_color_params;

	node = list->list;
	node_end = &list->list[list->len];
	for (; node != node_end ; node = next_node)
	{
		int empty;
		fz_display_node n = *node;

		next_node = node + n.size;

		/* Check the cookie for aborting */
		if (cookie)
		{
			if (cookie->abort)
				break;
			cookie->progress = progress;
			progress += n.size;
		}

		node++;
		if (n.rect)
		{
			rect = *(fz_rect *)node;
			node += SIZE_IN_NODES(sizeof(fz_rect));
		}
		if (n.cs)
		{
			int i, en;

			fz_drop_colorspace(ctx, colorspace);
			switch (n.cs)
			{
			default:
			case CS_GRAY_0:
				colorspace = fz_keep_colorspace(ctx, fz_device_gray(ctx));
				color[0] = 0.0f;
				break;
			case CS_GRAY_1:
				colorspace = fz_keep_colorspace(ctx, fz_device_gray(ctx));
				color[0] = 1.0f;
				break;
			case CS_RGB_0:
				colorspace = fz_keep_colorspace(ctx, fz_device_rgb(ctx));
				color[0] = 0.0f;
				color[1] = 0.0f;
				color[2] = 0.0f;
				break;
			case CS_RGB_1:
				colorspace = fz_keep_colorspace(ctx, fz_device_rgb(ctx));
				color[0] = 1.0f;
				color[1] = 1.0f;
				color[2] = 1.0f;
				break;
			case CS_CMYK_0:
				colorspace = fz_keep_colorspace(ctx, fz_device_cmyk(ctx));
				color[0] = 0.0f;
				color[1] = 0.0f;
				color[2] = 0.0f;
				color[3] = 0.0f;
				break;
			case CS_CMYK_1:
				colorspace = fz_keep_colorspace(ctx, fz_device_cmyk(ctx));
				color[0] = 0.0f;
				color[1] = 0.0f;
				color[2] = 0.0f;
				color[3] = 1.0f;
				break;
			case CS_OTHER_0:
				colorspace = fz_keep_colorspace(ctx, *(fz_colorspace **)(node));
				node += SIZE_IN_NODES(sizeof(fz_colorspace *));
				en = fz_colorspace_n(ctx, colorspace);
				for (i = 0; i < en; i++)
					color[i] = 0.0f;
				break;
			}
		}
		if (n.color)
		{
			int nc = fz_colorspace_n(ctx, colorspace);
			memcpy(color, (float *)node, nc * sizeof(float));
			node += SIZE_IN_NODES(nc * sizeof(float));
		}
		if (n.alpha)
		{
			switch(n.alpha)
			{
			default:
			case ALPHA_0:
				alpha = 0.0f;
				break;
			case ALPHA_1:
				alpha = 1.0f;
				break;
			case ALPHA_PRESENT:
				alpha = *(float *)node;
				node += SIZE_IN_NODES(sizeof(float));
				break;
			}
		}
		if (n.ctm != 0)
		{
			float *packed_ctm = (float *)node;
			if (n.ctm & CTM_CHANGE_AD)
			{
				ctm.a = *packed_ctm++;
				ctm.d = *packed_ctm++;
				node += SIZE_IN_NODES(2*sizeof(float));
			}
			if (n.ctm & CTM_CHANGE_BC)
			{
				ctm.b = *packed_ctm++;
				ctm.c = *packed_ctm++;
				node += SIZE_IN_NODES(2*sizeof(float));
			}
			if (n.ctm & CTM_CHANGE_EF)
			{
				ctm.e = *packed_ctm++;
				ctm.f = *packed_ctm;
				node += SIZE_IN_NODES(2*sizeof(float));
			}
		}
		if (n.stroke)
		{
			fz_drop_stroke_state(ctx, stroke);
			stroke = fz_keep_stroke_state(ctx, *(fz_stroke_state **)node);
			node += SIZE_IN_NODES(sizeof(fz_stroke_state *));
		}
		if (n.path)
		{
			fz_drop_path(ctx, path);
			path = fz_keep_path(ctx, (fz_path *)node);
			node += SIZE_IN_NODES(fz_packed_path_size(path));
		}

		if (tile_skip_depth > 0)
		{
			if (n.cmd == FZ_CMD_BEGIN_TILE)
				tile_skip_depth++;
			else if (n.cmd == FZ_CMD_END_TILE)
				tile_skip_depth--;
			if (tile_skip_depth > 0)
				continue;
		}

		trans_rect = fz_transform_rect(rect, top_ctm);

		/* cull objects to draw using a quick visibility test */

		if (tiled ||
			n.cmd == FZ_CMD_BEGIN_TILE || n.cmd == FZ_CMD_END_TILE ||
			n.cmd == FZ_CMD_RENDER_FLAGS || n.cmd == FZ_CMD_DEFAULT_COLORSPACES ||
			n.cmd == FZ_CMD_BEGIN_LAYER || n.cmd == FZ_CMD_END_LAYER)
		{
			empty = 0;
		}
		else
		{
			empty = fz_is_empty_rect(fz_intersect_rect(trans_rect, scissor));
		}

		if (clipped || empty)
		{
			switch (n.cmd)
			{
			case FZ_CMD_CLIP_PATH:
			case FZ_CMD_CLIP_STROKE_PATH:
			case FZ_CMD_CLIP_TEXT:
			case FZ_CMD_CLIP_STROKE_TEXT:
			case FZ_CMD_CLIP_IMAGE_MASK:
			case FZ_CMD_BEGIN_MASK:
			case FZ_CMD_BEGIN_GROUP:
				clipped++;
				continue;
			case FZ_CMD_POP_CLIP:
			case FZ_CMD_END_GROUP:
				if (!clipped)
					goto visible;
				clipped--;
				continue;
			case FZ_CMD_END_MASK:
				if (!clipped)
					goto visible;
				continue;
			default:
				continue;
			}
		}

visible:
		trans_ctm = fz_concat(ctm, top_ctm);

		fz_try(ctx)
		{
			switch (n.cmd)
			{
			case FZ_CMD_FILL_PATH:
				fz_unpack_color_params(&color_params, n.flags);
				fz_fill_path(ctx, dev, path, n.flags & 1, trans_ctm, colorspace, color, alpha, color_params);
				break;
			case FZ_CMD_STROKE_PATH:
				fz_unpack_color_params(&color_params, n.flags);
				fz_stroke_path(ctx, dev, path, stroke, trans_ctm, colorspace, color, alpha, color_params);
				break;
			case FZ_CMD_CLIP_PATH:
				fz_clip_path(ctx, dev, path, n.flags, trans_ctm, trans_rect);
				break;
			case FZ_CMD_CLIP_STROKE_PATH:
				fz_clip_stroke_path(ctx, dev, path, stroke, trans_ctm, trans_rect);
				break;
			case FZ_CMD_FILL_TEXT:
				fz_unpack_color_params(&color_params, n.flags);
				fz_fill_text(ctx, dev, *(fz_text **)node, trans_ctm, colorspace, color, alpha, color_params);
				break;
			case FZ_CMD_STROKE_TEXT:
				fz_unpack_color_params(&color_params, n.flags);
				fz_stroke_text(ctx, dev, *(fz_text **)node, stroke, trans_ctm, colorspace, color, alpha, color_params);
				break;
			case FZ_CMD_CLIP_TEXT:
				fz_clip_text(ctx, dev, *(fz_text **)node, trans_ctm, trans_rect);
				break;
			case FZ_CMD_CLIP_STROKE_TEXT:
				fz_clip_stroke_text(ctx, dev, *(fz_text **)node, stroke, trans_ctm, trans_rect);
				break;
			case FZ_CMD_IGNORE_TEXT:
				fz_ignore_text(ctx, dev, *(fz_text **)node, trans_ctm);
				break;
			case FZ_CMD_FILL_SHADE:
				fz_unpack_color_params(&color_params, n.flags);
				fz_fill_shade(ctx, dev, *(fz_shade **)node, trans_ctm, alpha, color_params);
				break;
			case FZ_CMD_FILL_IMAGE:
				fz_unpack_color_params(&color_params, n.flags);
				fz_fill_image(ctx, dev, *(fz_image **)node, trans_ctm, alpha, color_params);
				break;
			case FZ_CMD_FILL_IMAGE_MASK:
				fz_unpack_color_params(&color_params, n.flags);
				fz_fill_image_mask(ctx, dev, *(fz_image **)node, trans_ctm, colorspace, color, alpha, color_params);
				break;
			case FZ_CMD_CLIP_IMAGE_MASK:
				fz_clip_image_mask(ctx, dev, *(fz_image **)node, trans_ctm, trans_rect);
				break;
			case FZ_CMD_POP_CLIP:
				fz_pop_clip(ctx, dev);
				break;
			case FZ_CMD_BEGIN_MASK:
				fz_unpack_color_params(&color_params, n.flags);
				fz_begin_mask(ctx, dev, trans_rect, n.flags & 1, colorspace, color, color_params);
				break;
			case FZ_CMD_END_MASK:
				fz_end_mask(ctx, dev);
				break;
			case FZ_CMD_BEGIN_GROUP:
				fz_begin_group(ctx, dev, trans_rect, *(fz_colorspace **)node, (n.flags & ISOLATED) != 0, (n.flags & KNOCKOUT) != 0, (n.flags>>2), alpha);
				break;
			case FZ_CMD_END_GROUP:
				fz_end_group(ctx, dev);
				break;
			case FZ_CMD_BEGIN_TILE:
			{
				int cached;
				fz_list_tile_data *data = (fz_list_tile_data *)node;
				fz_rect tile_rect;
				tiled++;
				tile_rect = data->view;
				cached = fz_begin_tile_id(ctx, dev, rect, tile_rect, data->xstep, data->ystep, trans_ctm, data->id);
				if (cached)
					tile_skip_depth = 1;
				break;
			}
			case FZ_CMD_END_TILE:
				tiled--;
				fz_end_tile(ctx, dev);
				break;
			case FZ_CMD_RENDER_FLAGS:
				if (n.flags == 0)
					fz_render_flags(ctx, dev, 0, FZ_DEVFLAG_GRIDFIT_AS_TILED);
				else if (n.flags == 1)
					fz_render_flags(ctx, dev, FZ_DEVFLAG_GRIDFIT_AS_TILED, 0);
				break;
			case FZ_CMD_DEFAULT_COLORSPACES:
				fz_set_default_colorspaces(ctx, dev, *(fz_default_colorspaces **)node);
				break;
			case FZ_CMD_BEGIN_LAYER:
				fz_begin_layer(ctx, dev, (const char *)node);
				break;
			case FZ_CMD_END_LAYER:
				fz_end_layer(ctx, dev);
				break;
			}
		}
		fz_catch(ctx)
		{
			/* Swallow the error */
			if (cookie)
				cookie->errors++;
			if (fz_caught(ctx) == FZ_ERROR_ABORT)
				break;
			fz_warn(ctx, "Ignoring error during interpretation");
		}
	}
	fz_drop_colorspace(ctx, colorspace);
	fz_drop_stroke_state(ctx, stroke);
	fz_drop_path(ctx, path);
	if (cookie)
		cookie->progress = progress;
}