plan9fox/sys/include/memdraw.h
cinap_lenrek 71dbddef16 draw: fix drawing of replicated source image on memlayer with a clip rectangle
when a replicated source image with a clipr with clipr.min > Pt(0, 0),
drawclip() would properly translate the src->clipr on the dstr
but then clamp the source rectangle back on src->r.

while traversing down multiple layers, this would cause the translation to
be applied multiple times to the dst rectangle giving the wrong image result.

this change adds a new drawclipnorepl() function that avoids the clamping
of source and mask rectangles to src->r and mask->r. this is then used in
libmemlayer.

the final memimagedraw() call will call drawclip() which will do the final
claming.

a testcase is provided:

#include <u.h>
#include <libc.h>
#include <draw.h>

Image *blue;
Image *red;

void
main(int, char *argv[])
{
	Image *i;

	if(initdraw(nil, nil, argv[0]) < 0)
		sysfatal("initdraw: %r");
	i = allocimage(display, screen->r, screen->chan, 1, DWhite);

	red = allocimage(display, Rect(0,0,1,1), screen->chan, 1, DRed);
	blue = allocimage(display, Rect(0,0,1,1), screen->chan, 1, DPaleblue);
	replclipr(red, 1, Rect(10, 10, 110, 110));
	replclipr(blue, 1, Rect(11, 11, 111, 111));

	/* draw on non-layer, works correctly */
	draw(i, i->r, red, nil, ZP);
	draw(i, i->r, blue, nil, ZP);
	draw(screen, screen->r, i, nil, i->r.min);
	flushimage(display, 1);

	/* draw on (screen) layer is too far to the right */
	draw(screen, screen->r, red, nil, ZP);
	draw(screen, screen->r, blue, nil, ZP);
	flushimage(display, 1);

	for(;;){
		sleep(1000);
	}
}
2013-12-09 03:35:01 +01:00

195 lines
5.6 KiB
C

#pragma src "/sys/src/libmemdraw"
#pragma lib "libmemdraw.a"
typedef struct Memimage Memimage;
typedef struct Memdata Memdata;
typedef struct Memsubfont Memsubfont;
typedef struct Memlayer Memlayer;
typedef struct Memcmap Memcmap;
typedef struct Memdrawparam Memdrawparam;
#pragma incomplete Memlayer
/*
* Memdata is allocated from main pool, but .data from the image pool.
* Memdata is allocated separately to permit patching its pointer after
* compaction when windows share the image data.
* The first word of data is a back pointer to the Memdata, to find
* The word to patch.
*/
struct Memdata
{
ulong *base; /* allocated data pointer */
uchar *bdata; /* pointer to first byte of actual data; word-aligned */
int ref; /* number of Memimages using this data */
void* imref;
int allocd; /* is this malloc'd? */
};
enum {
Frepl = 1<<0, /* is replicated */
Fsimple = 1<<1, /* is 1x1 */
Fgrey = 1<<2, /* is grey */
Falpha = 1<<3, /* has explicit alpha */
Fcmap = 1<<4, /* has cmap channel */
Fbytes = 1<<5, /* has only 8-bit channels */
};
struct Memimage
{
Rectangle r; /* rectangle in data area, local coords */
Rectangle clipr; /* clipping region */
int depth; /* number of bits of storage per pixel */
int nchan; /* number of channels */
ulong chan; /* channel descriptions */
Memcmap *cmap;
Memdata *data; /* pointer to data; shared by windows in this image */
int zero; /* data->bdata+zero==&byte containing (0,0) */
ulong width; /* width in words of a single scan line */
Memlayer *layer; /* nil if not a layer*/
ulong flags;
int shift[NChan];
int mask[NChan];
int nbits[NChan];
};
struct Memcmap
{
uchar cmap2rgb[3*256];
uchar rgb2cmap[16*16*16];
};
/*
* Subfonts
*
* given char c, Subfont *f, Fontchar *i, and Point p, one says
* i = f->info+c;
* draw(b, Rect(p.x+i->left, p.y+i->top,
* p.x+i->left+((i+1)->x-i->x), p.y+i->bottom),
* color, f->bits, Pt(i->x, i->top));
* p.x += i->width;
* to draw characters in the specified color (itself a Memimage) in Memimage b.
*/
struct Memsubfont
{
char *name;
short n; /* number of chars in font */
uchar height; /* height of bitmap */
char ascent; /* top of bitmap to baseline */
Fontchar *info; /* n+1 character descriptors */
Memimage *bits; /* of font */
};
/*
* Encapsulated parameters and information for sub-draw routines.
*/
enum {
Simplesrc=1<<0,
Simplemask=1<<1,
Replsrc=1<<2,
Replmask=1<<3,
Fullmask=1<<4,
};
struct Memdrawparam
{
Memimage *dst;
Rectangle r;
Memimage *src;
Rectangle sr;
Memimage *mask;
Rectangle mr;
int op;
ulong state;
ulong mval; /* if Simplemask, the mask pixel in mask format */
ulong mrgba; /* mval in rgba */
ulong sval; /* if Simplesrc, the source pixel in src format */
ulong srgba; /* sval in rgba */
ulong sdval; /* sval in dst format */
};
/*
* Memimage management
*/
extern Memimage* allocmemimage(Rectangle, ulong);
extern Memimage* allocmemimaged(Rectangle, ulong, Memdata*);
extern Memimage* readmemimage(int);
extern Memimage* creadmemimage(int);
extern int writememimage(int, Memimage*);
extern void freememimage(Memimage*);
extern int loadmemimage(Memimage*, Rectangle, uchar*, int);
extern int cloadmemimage(Memimage*, Rectangle, uchar*, int);
extern int unloadmemimage(Memimage*, Rectangle, uchar*, int);
extern ulong* wordaddr(Memimage*, Point);
extern uchar* byteaddr(Memimage*, Point);
extern int drawclipnorepl(Memimage*, Rectangle*, Memimage*, Point*, Memimage*, Point*, Rectangle*, Rectangle*);
extern int drawclip(Memimage*, Rectangle*, Memimage*, Point*, Memimage*, Point*, Rectangle*, Rectangle*);
extern void memfillcolor(Memimage*, ulong);
extern int memsetchan(Memimage*, ulong);
/*
* Graphics
*/
extern void memdraw(Memimage*, Rectangle, Memimage*, Point, Memimage*, Point, int);
extern void memline(Memimage*, Point, Point, int, int, int, Memimage*, Point, int);
extern void mempoly(Memimage*, Point*, int, int, int, int, Memimage*, Point, int);
extern void memfillpoly(Memimage*, Point*, int, int, Memimage*, Point, int);
extern void _memfillpolysc(Memimage*, Point*, int, int, Memimage*, Point, int, int, int, int);
extern void memimagedraw(Memimage*, Rectangle, Memimage*, Point, Memimage*, Point, int);
extern int hwdraw(Memdrawparam*);
extern void memimageline(Memimage*, Point, Point, int, int, int, Memimage*, Point, int);
extern void _memimageline(Memimage*, Point, Point, int, int, int, Memimage*, Point, Rectangle, int);
extern Point memimagestring(Memimage*, Point, Memimage*, Point, Memsubfont*, char*);
extern void memellipse(Memimage*, Point, int, int, int, Memimage*, Point, int);
extern void memarc(Memimage*, Point, int, int, int, Memimage*, Point, int, int, int);
extern Rectangle memlinebbox(Point, Point, int, int, int);
extern int memlineendsize(int);
extern void _memmkcmap(void);
extern int memimageinit(void);
/*
* Subfont management
*/
extern Memsubfont* allocmemsubfont(char*, int, int, int, Fontchar*, Memimage*);
extern Memsubfont* openmemsubfont(char*);
extern void freememsubfont(Memsubfont*);
extern Point memsubfontwidth(Memsubfont*, char*);
extern Memsubfont* getmemdefont(void);
/*
* Predefined
*/
extern Memimage* memwhite;
extern Memimage* memblack;
extern Memimage* memopaque;
extern Memimage* memtransparent;
extern Memcmap *memdefcmap;
/*
* Kernel interface
*/
void memimagemove(void*, void*);
/*
* Kernel cruft
*/
extern void rdb(void);
extern int iprint(char*, ...);
#pragma varargck argpos iprint 1
extern int drawdebug;
/*
* doprint interface: numbconv bit strings
*/
#pragma varargck type "llb" vlong
#pragma varargck type "llb" uvlong
#pragma varargck type "lb" long
#pragma varargck type "lb" ulong
#pragma varargck type "b" int
#pragma varargck type "b" uint