upiwin/src/devctxt.c

172 lines
3.9 KiB
C
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#include <string.h>
#include "gfxtype.h"
#include "gfxobj.h"
#include "devctxt.h"
inline static BYTE line_clip_outcode(INT32 x, INT32 y, INT32 xmin, INT32 ymin, INT32 xmax, INT32 ymax)
{
BYTE rc = 0;
if (y < ymin)
rc |= 0x8;
else if (y >= ymax)
rc |= 0x4;
if (x < xmin)
rc |= 0x1;
else if (x >= xmax)
rc |= 0x2;
return rc;
}
static BOOL line_clip(PINT32 output, INT32 x1, INT32 y1, INT32 x2, INT32 y2, INT32 xmin, INT32 ymin, INT32 xmax, INT32 ymax)
{
BYTE outcode1, outcode2, tmpb;
INT32 tmp;
/* Cohen-Sutherland line-clipping algorithm (see Foley & Van Dam, pp. 145-149) */
for (;;)
{
outcode1 = line_clip_outcode(x1, y1, xmin, ymin, xmax, ymax);
outcode2 = line_clip_outcode(x2, y2, xmin, ymin, xmax, ymax);
if ((outcode1 & outcode2) != 0)
return FALSE; /* trivial rejection */
else if ((outcode1 == 0) && (outcode2 == 0))
break; /* trivial acceptance */
if (outcode1 == 0)
{
tmp = x1;
x1 = x2;
x2 = tmp;
tmp = y1;
y1 = y2;
y2 = tmp;
tmpb = outcode1;
outcode1 = outcode2;
outcode2 = tmp;
}
if (outcode1 & 0x8)
{
x1 += (x2 - x1) * (ymin - y1) / (y2 - y1);
y1 = ymin;
}
else if (outcode1 & 0x4)
{
x1 += (x2 - x1) * (ymax - y1) / (y2 - y1);
y1 = ymax;
}
else if (outcode1 & 0x2)
{
y1 += (y2 - y1) * (xmax - x1) / (x2 - x1);
x1 = xmax;
}
else if (outcode1 & 0x1)
{
y1 += (y2 - y1) * (xmin - x1) / (x2 - x1);
x1 = xmin;
}
}
output[0] = x1;
output[1] = y1;
output[2] = x2;
output[3] = y2;
return TRUE;
}
static BOOL internal_line(PDCTXT pdctxt, INT32 x1, INT32 y1, INT32 x2, INT32 y2)
{
INT32 buffer[4];
if (line_clip(buffer, x1 << 16, y1 << 16, x2 << 16, y2 << 16, pdctxt->cliprect.left << 16, pdctxt->cliprect.top << 16,
pdctxt->cliprect.right << 16, pdctxt->cliprect.bottom << 16))
return (*pdctxt->funcs->line)(pdctxt->privdata, buffer[0] >> 16, buffer[1] >> 16, buffer[2] >> 16, buffer[3] >> 16, pdctxt->color, pdctxt->rop2);
return TRUE;
}
PDCTXT _DC_Allocate(PDCFUNTABLE funcs, PVOID privdata)
{
PDCTXT rc = (PDCTXT)malloc(sizeof(DCTXT));
if (!rc)
return NULL;
memset(rc, 0, sizeof(DCTXT));
_Go_init(&(rc->hdr), DCTXT_SIG_WORD, sizeof(DCTXT));
rc->funcs = funcs;
rc->privdata = privdata;
rc->rop2 = R2_COPYPEN;
return rc;
}
void _DC_FinalizeCommon(PDCTXT pdctxt)
{
/* nothing here yet */
}
COLORREF DC_SetPixel(PDCTXT pdctxt, INT32 x, INT32 y, COLORREF color)
{
if (!G_coords_in_rect(&(pdctxt->cliprect), x, y))
return (COLORREF)(-1);
return (*(pdctxt->funcs->set_pixel))(pdctxt->privdata, xm, y, colorref, pdctxt->rop2);
}
BOOL DC_LineTo(PDCTXT pdctxt, INT32 x, INT32 y)
{
BOOL rc = internal_line(pdctxt, pdctxt->pos.x, pdctxt->pos.y, x, y);
if (rc)
{
pdctxt->pos.x = x;
pdctxt->pos.y = y;
}
return rc;
}
BOOL DC_MoveTo(PDCTXT pdctxt, INT32 x, INT32 y, PPOINT oldpt)
{
if (oldpt)
memcpy(oldpt, &(pdctxt->pos), sizeof(POINT));
pdctxt->pos.x = x;
pdctxt->pos.y = y;
return TRUE;
}
BOOL DC_Rectangle(PDCTXT pdctxt, INT32 left, INT32 top, INT32 right, INT32 bottom)
{
internal_line(pdctxt, left, top, right - 1, top);
internal_line(pdctxt, left, top + 1, left, bottom - 2);
internal_line(pdctxt, right - 1, top + 1, right - 1, bottom - 2);
internal_line(pdctxt, left, bottom - 1, right - 1, bottom - 1);
return TRUE;
}
UINT32 DC_GetROP2(PDCTXT pdctxt)
{
return pdctxt->rop2;
}
UINT32 DC_SetROP2(PDCTXT pdctxt, UINT32 rop)
{
UINT32 rc = pdctxt->rop2;
pdctxt->rop2 = rop;
return rc;
}
COLORREF DC_GetTextColor(PDCTXT pdctxt)
{
return pdctxt->color;
}
COLORREF DC_SetTextColor(PDCTXT pdctxt, COLORREF cr)
{
COLORREF rc = pdctxt->color;
pdctxt->color = cr;
return rc;
}
BOOL DC_GetClipRect(PDCTXT pdctxt, PRECT prect)
{
memcpy(prect, &(pdctxt->cliprect), sizeof(RECT));
return TRUE;
}
BOOL DC_SetClipRect(PDCTXT pdctxt, PRECT prect)
{
memcpy(&(pdctxt->cliprect), prect, sizeof(RECT));
return TRUE;
}