Mercurial > hg > dmlib
annotate dmline.c @ 96:6bf5220fa47e
Urgh .. use memset to silence some bogus GCC warnings about using
potentially uninitialized values, while that will not actually be possible.
In any case, it is annoying.
| author | Matti Hamalainen <ccr@tnsp.org> |
|---|---|
| date | Tue, 02 Oct 2012 18:52:28 +0300 |
| parents | 997e26f17946 |
| children | 92cc5e1fa180 |
| rev | line source |
|---|---|
| 0 | 1 /* |
| 2 * DMLib | |
| 3 * -- Arbitrary line drawing functions | |
| 4 * Programmed and designed by Matti 'ccr' Hamalainen | |
| 5 * (C) Copyright 2011 Tecnic Software productions (TNSP) | |
| 6 */ | |
| 7 #include "dmlib.h" | |
| 8 | |
| 9 | |
| 10 /* Clip line coordinates. Return value: | |
| 11 * = 0 : No clipping needed. | |
| 12 * > 0 : Clipped. Line partially inside the clipping area. | |
| 13 * < 0 : Line completely outside the clipping area. | |
| 14 */ | |
| 15 int dmClipLineCoords(int *x0, int *y0, int *x1, int *y1, SDL_Surface *screen) | |
| 16 { | |
| 17 #if 0 | |
| 18 const int clipX0 = screen->clip_rect.x, | |
| 19 clipY0 = screen->clip_rect.y; | |
| 20 const int clipX1 = clipX0 + screen->clip_rect.w - 1, | |
| 21 clipY1 = clipY0 + screen->clip_rect.h - 1; | |
| 22 const int dx = *x1 - *x0, | |
| 23 dy = *y1 - *y0; | |
| 24 DMFixedPoint k, kdx, kdy; | |
| 25 | |
| 26 // Is line completely outside the clipping area? | |
| 27 if ((*x0 < clipX0 && *x1 < clipX0) || (*x0 > clipX1 && *x1 > clipX1) || | |
| 28 (*y0 < clipY0 && *y1 < clipY0) || (*y0 > clipY1 && *y1 > clipY1)) | |
| 29 return -1; | |
| 30 | |
| 31 FP_SETHL(kdx, dx); | |
| 32 FP_SETHL(kdy, dy); | |
| 33 #endif | |
| 34 | |
| 35 return 0; | |
| 36 } | |
| 37 | |
| 38 | |
| 39 int dmTestLineCoords(int x0, int y0, int x1, int y1, SDL_Surface *screen) | |
| 40 { | |
| 41 return dmClipLineCoords(&x0, &y0, &x1, &y1, screen); | |
| 42 } | |
| 43 | |
| 44 | |
| 45 #include "dmlinefunc.h" | |
| 46 | |
| 47 static const DMDrawLineFunc dmDrawLineTable[DMD_NMODES][DMD_NBITDEPTHS] = | |
| 48 { | |
| 49 /* DMD_NONE */ { dmDrawLine8 , dmDrawLine32 }, | |
|
22
997e26f17946
Initial fixes for getting the line drawing functions "working".
Matti Hamalainen <ccr@tnsp.org>
parents:
0
diff
changeset
|
50 #if 0 |
| 0 | 51 /* DMD_TRANSPARENT */ { dmDrawLine8Transparent , dmDrawLine32Transparent }, |
| 52 /* DMD_SATURATE */ { dmDrawLine8Saturate , dmDrawLine32Saturate }, | |
|
22
997e26f17946
Initial fixes for getting the line drawing functions "working".
Matti Hamalainen <ccr@tnsp.org>
parents:
0
diff
changeset
|
53 |
| 0 | 54 /* DMD_NONE + AA */ { NULL, NULL }, |
| 55 /* DMD_TRANSP + AA */ { NULL, NULL }, | |
| 56 /* DMD_SATURATE + AA */ { dmDrawLine8AASaturate , dmDrawLine32AASaturate }, | |
|
22
997e26f17946
Initial fixes for getting the line drawing functions "working".
Matti Hamalainen <ccr@tnsp.org>
parents:
0
diff
changeset
|
57 #endif |
| 0 | 58 }; |
| 59 | |
|
22
997e26f17946
Initial fixes for getting the line drawing functions "working".
Matti Hamalainen <ccr@tnsp.org>
parents:
0
diff
changeset
|
60 static const int ndmDrawLineTable = sizeof(dmDrawLineTable) / sizeof(dmDrawLineTable[0]); |
|
997e26f17946
Initial fixes for getting the line drawing functions "working".
Matti Hamalainen <ccr@tnsp.org>
parents:
0
diff
changeset
|
61 |
| 0 | 62 |
| 63 DMDrawLineFunc dmGetDrawLineFunc(SDL_PixelFormat *dst, int mode) | |
| 64 { | |
| 65 int index; | |
|
22
997e26f17946
Initial fixes for getting the line drawing functions "working".
Matti Hamalainen <ccr@tnsp.org>
parents:
0
diff
changeset
|
66 if (dst == NULL || mode < 0 || mode >= ndmDrawLineTable) |
| 0 | 67 return NULL; |
| 68 | |
|
22
997e26f17946
Initial fixes for getting the line drawing functions "working".
Matti Hamalainen <ccr@tnsp.org>
parents:
0
diff
changeset
|
69 if ((index = dmBitsPerPixel2Index(dst->BitsPerPixel)) < 0) |
| 0 | 70 return NULL; |
| 71 | |
|
22
997e26f17946
Initial fixes for getting the line drawing functions "working".
Matti Hamalainen <ccr@tnsp.org>
parents:
0
diff
changeset
|
72 return dmDrawLineTable[mode][index]; |
| 0 | 73 } |
| 74 | |
| 75 | |
| 76 int dmDrawLineAny(SDL_Surface *screen, int x0, int y0, int x1, int y1, const Uint32 col, int mode) | |
| 77 { | |
| 78 DMDrawLineFunc bfunc = dmGetDrawLineFunc(screen->format, mode); | |
| 79 | |
| 80 if (bfunc == NULL) | |
| 81 return -15; | |
| 82 | |
| 83 return bfunc(screen, x0, y0, x1, y1, col); | |
| 84 } |