2 THE COMPUTER CODE CONTAINED HEREIN IS THE SOLE PROPERTY OF PARALLAX
3 SOFTWARE CORPORATION ("PARALLAX"). PARALLAX, IN DISTRIBUTING THE CODE TO
4 END-USERS, AND SUBJECT TO ALL OF THE TERMS AND CONDITIONS HEREIN, GRANTS A
5 ROYALTY-FREE, PERPETUAL LICENSE TO SUCH END-USERS FOR USE BY SUCH END-USERS
6 IN USING, DISPLAYING, AND CREATING DERIVATIVE WORKS THEREOF, SO LONG AS
7 SUCH USE, DISPLAY OR CREATION IS FOR NON-COMMERCIAL, ROYALTY OR REVENUE
8 FREE PURPOSES. IN NO EVENT SHALL THE END-USER USE THE COMPUTER CODE
9 CONTAINED HEREIN FOR REVENUE-BEARING PURPOSES. THE END-USER UNDERSTANDS
10 AND AGREES TO THE TERMS HEREIN AND ACCEPTS THE SAME BY USE OF THIS FILE.
11 COPYRIGHT 1993-1998 PARALLAX SOFTWARE CORPORATION. ALL RIGHTS RESERVED.
15 * Routines for scaling a bitmap.
34 #define TRANSPARENCY_COLOR 255;
40 static int Transparency_color = TRANSPARENCY_COLOR;
42 void rls_stretch_scanline( char * source, char * dest, int XDelta, int YDelta );
43 void rls_stretch_scanline_setup( int XDelta, int YDelta );
44 void scale_bitmap_asm(grs_bitmap *source_bmp, grs_bitmap *dest_bmp, int x0, int y0, int x1, int y1, fix u0, fix v0, fix u1, fix v1 );
45 void scale_bitmap_asm_rle(grs_bitmap *source_bmp, grs_bitmap *dest_bmp, int x0, int y0, int x1, int y1, fix u0, fix v0, fix u1, fix v1 );
46 void scale_bitmap_cc_asm(grs_bitmap *source_bmp, grs_bitmap *dest_bmp, int x0, int y0, int x1, int y1, fix u0, fix v0, fix u1, fix v1 );
47 void scale_bitmap_cc_asm_rle(grs_bitmap *source_bmp, grs_bitmap *dest_bmp, int x0, int y0, int x1, int y1, fix u0, fix v0, fix u1, fix v1 );
49 void scale_row_c( ubyte * sbits, ubyte * dbits, int width, fix u, fix du )
54 for ( i=0; i<width; i++ ) {
57 if ( c != Transparency_color )
65 #define FIND_SCALED_NUM(x,x0,x1,y0,y1) (fixmuldiv((x)-(x0),(y1)-(y0),(x1)-(x0))+(y0))
67 // Scales bitmap, bp, into vertbuf[0] to vertbuf[1]
68 void scale_bitmap(grs_bitmap *bp, grs_point *vertbuf ,int orientation)
70 grs_bitmap * dbp = &grd_curcanv->cv_bitmap;
73 fix clipped_x0, clipped_y0, clipped_x1, clipped_y1;
74 fix clipped_u0, clipped_v0, clipped_u1, clipped_v1;
75 fix xmin, xmax, ymin, ymax;
76 int dx0, dy0, dx1, dy1;
78 // Set initial variables....
80 x0 = vertbuf[0].x; y0 = vertbuf[0].y;
81 x1 = vertbuf[2].x; y1 = vertbuf[2].y;
84 xmax = i2f(dbp->bm_w)-fl2f(.5); ymax = i2f(dbp->bm_h)-fl2f(.5);
86 u0 = i2f(0); v0 = i2f(0);
87 u1 = i2f(bp->bm_w-1); v1 = i2f(bp->bm_h-1);
89 // Check for obviously offscreen bitmaps...
90 if ( (y1<=y0) || (x1<=x0) ) return;
91 if ( (x1<0 ) || (x0>=xmax) ) return;
92 if ( (y1<0 ) || (y0>=ymax) ) return;
94 clipped_u0 = u0; clipped_v0 = v0;
95 clipped_u1 = u1; clipped_v1 = v1;
97 clipped_x0 = x0; clipped_y0 = y0;
98 clipped_x1 = x1; clipped_y1 = y1;
100 // Clip the left, moving u0 right as necessary
102 clipped_u0 = FIND_SCALED_NUM(xmin,x0,x1,u0,u1);
106 // Clip the right, moving u1 left as necessary
108 clipped_u1 = FIND_SCALED_NUM(xmax,x0,x1,u0,u1);
112 // Clip the top, moving v0 down as necessary
114 clipped_v0 = FIND_SCALED_NUM(ymin,y0,y1,v0,v1);
118 // Clip the bottom, moving v1 up as necessary
120 clipped_v1 = FIND_SCALED_NUM(ymax,y0,y1,v0,v1);
124 dx0 = f2i(clipped_x0); dx1 = f2i(clipped_x1);
125 dy0 = f2i(clipped_y0); dy1 = f2i(clipped_y1);
127 if (dx1<=dx0) return;
128 if (dy1<=dy0) return;
132 Assert( dx1<dbp->bm_w );
133 Assert( dy1<dbp->bm_h );
134 Assert( f2i(u0)<=f2i(u1) );
135 Assert( f2i(v0)<=f2i(v1) );
136 Assert( f2i(u0)>=0 );
137 Assert( f2i(v0)>=0 );
138 Assert( u1<i2f(bp->bm_w) );
139 Assert( v1<i2f(bp->bm_h) );
141 //mprintf( 0, "(%.2f,%.2f) to (%.2f,%.2f) using (%.2f,%.2f) to (%.2f,%.2f)\n", f2fl(clipped_x0), f2fl(clipped_y0), f2fl(clipped_x1), f2fl(clipped_y1), f2fl(clipped_u0), f2fl(clipped_v0), f2fl(clipped_u1), f2fl(clipped_v1) );
143 dtemp = f2i(clipped_u1)-f2i(clipped_u0);
145 if ( bp->bm_flags & BM_FLAG_RLE ) {
146 if ( (dtemp < (f2i(clipped_x1)-f2i(clipped_x0))) && (dtemp>0) )
147 scale_bitmap_cc_asm_rle(bp, dbp, dx0, dy0, dx1, dy1, clipped_u0, clipped_v0, clipped_u1, clipped_v1 );
149 scale_bitmap_asm_rle(bp, dbp, dx0, dy0, dx1, dy1, clipped_u0, clipped_v0, clipped_u1, clipped_v1 );
151 if ( (dtemp < (f2i(clipped_x1)-f2i(clipped_x0))) && (dtemp>0) )
152 scale_bitmap_cc_asm(bp, dbp, dx0, dy0, dx1, dy1, clipped_u0, clipped_v0, clipped_u1, clipped_v1 );
154 scale_bitmap_asm(bp, dbp, dx0, dy0, dx1, dy1, clipped_u0, clipped_v0, clipped_u1, clipped_v1 );
159 void scale_bitmap_c(grs_bitmap *source_bmp, grs_bitmap *dest_bmp, int x0, int y0, int x1, int y1, fix u0, fix v0, fix u1, fix v1 )
163 ubyte * sbits, * dbits;
165 du = (u1-u0) / (x1-x0);
166 dv = (v1-v0) / (y1-y0);
170 for (y=y0; y<=y1; y++ ) {
171 sbits = &source_bmp->bm_data[source_bmp->bm_rowsize*f2i(v)];
172 dbits = &dest_bmp->bm_data[dest_bmp->bm_rowsize*y+x0];
175 for (x=x0; x<=x1; x++ ) {
176 *dbits++ = sbits[ u >> 16 ];
182 void scale_bitmap_asm(grs_bitmap *source_bmp, grs_bitmap *dest_bmp, int x0, int y0, int x1, int y1, fix u0, fix v0, fix u1, fix v1 )
187 du = (u1-u0) / (x1-x0);
188 dv = (v1-v0) / (y1-y0);
192 for (y=y0; y<=y1; y++ ) {
193 scale_row_asm_transparent( &source_bmp->bm_data[source_bmp->bm_rowsize*f2i(v)], &dest_bmp->bm_data[dest_bmp->bm_rowsize*y+x0], x1-x0+1, u0, du );
198 ubyte scale_rle_data[640];
200 void decode_row( grs_bitmap * bmp, int y )
202 int i, offset=4+bmp->bm_h;
205 offset += bmp->bm_data[4+i];
206 gr_rle_decode( &bmp->bm_data[offset], scale_rle_data );
209 void scale_bitmap_asm_rle(grs_bitmap *source_bmp, grs_bitmap *dest_bmp, int x0, int y0, int x1, int y1, fix u0, fix v0, fix u1, fix v1 )
214 du = (u1-u0) / (x1-x0);
215 dv = (v1-v0) / (y1-y0);
219 for (y=y0; y<=y1; y++ ) {
220 if ( f2i(v) != last_row ) {
222 decode_row( source_bmp, last_row );
224 scale_row_asm_transparent( scale_rle_data, &dest_bmp->bm_data[dest_bmp->bm_rowsize*y+x0], x1-x0+1, u0, du );
230 void scale_bitmap_cc_asm(grs_bitmap *source_bmp, grs_bitmap *dest_bmp, int x0, int y0, int x1, int y1, fix u0, fix v0, fix u1, fix v1 )
235 dv = (v1-v0) / (y1-y0);
237 rls_stretch_scanline_setup( (int)(x1-x0), f2i(u1)-f2i(u0) );
238 if ( scale_ydelta_minus_1 < 1 ) return;
239 rls_do_cc_setup_asm();
243 for (y=y0; y<=y1; y++ ) {
244 scale_source_ptr = &source_bmp->bm_data[source_bmp->bm_rowsize*f2i(v)+f2i(u0)];
245 scale_dest_ptr = &dest_bmp->bm_data[dest_bmp->bm_rowsize*y+x0];
246 scale_do_cc_scanline();
251 void scale_bitmap_cc_asm_rle(grs_bitmap *source_bmp, grs_bitmap *dest_bmp, int x0, int y0, int x1, int y1, fix u0, fix v0, fix u1, fix v1 )
254 int y, last_row = -1;
256 dv = (v1-v0) / (y1-y0);
258 rls_stretch_scanline_setup( (int)(x1-x0), f2i(u1)-f2i(u0) );
259 if ( scale_ydelta_minus_1 < 1 ) return;
260 rls_do_cc_setup_asm();
264 for (y=y0; y<=y1; y++ ) {
265 if ( f2i(v) != last_row ) {
267 decode_row( source_bmp, last_row );
269 //scale_source_ptr = &source_bmp->bm_data[source_bmp->bm_rowsize*f2i(v)+f2i(u0)];
270 scale_source_ptr = &scale_rle_data[f2i(u0)];
271 scale_dest_ptr = &dest_bmp->bm_data[dest_bmp->bm_rowsize*y+x0];
272 scale_do_cc_scanline();
279 // Run-length slice bitmap scan line stretcher
281 void DrawHorizontalRun(char *ScreenPtr, int RunLength, int Color)
285 for (i=0; i<RunLength; i++)
286 *ScreenPtr++ = Color;
289 void rls_stretch_scanline( char * source, char * dest, int XDelta, int YDelta )
291 int AdjUp, AdjDown, ErrorTerm;
292 int WholeStep, InitialPixelCount, FinalPixelCount, i, RunLength;
295 /* Minimum # of pixels in a run in this line */
296 WholeStep = XDelta / YDelta;
298 /* Error term adjust each time Y steps by 1; used to tell when one
299 extra pixel should be drawn as part of a run, to account for
300 fractional steps along the X axis per 1-pixel steps along Y */
301 AdjUp = (XDelta % YDelta) * 2;
303 /* Error term adjust when the error term turns over, used to factor
304 out the X step made at that time */
305 AdjDown = YDelta * 2;
307 /* Initial error term; reflects an initial step of 0.5 along the Y
309 ErrorTerm = (XDelta % YDelta) - (YDelta * 2);
311 /* The initial and last runs are partial, because Y advances only 0.5
312 for these runs, rather than 1. Divide one full run, plus the
313 initial pixel, between the initial and last runs */
314 InitialPixelCount = (WholeStep / 2) + 1;
315 FinalPixelCount = InitialPixelCount;
317 /* If the basic run length is even and there's no fractional
318 advance, we have one pixel that could go to either the initial
319 or last partial run, which we'll arbitrarily allocate to the
321 if ((AdjUp == 0) && ((WholeStep & 0x01) == 0))
325 /* If there're an odd number of pixels per run, we have 1 pixel that can't
326 be allocated to either the initial or last partial run, so we'll add 0.5
327 to error term so this pixel will be handled by the normal full-run loop */
328 if ((WholeStep & 0x01) != 0)
332 /* Draw the first, partial run of pixels */
333 //if ( *source != Transparency_color )
334 rep_stosb(dest, InitialPixelCount, *source );
335 dest += InitialPixelCount;
338 /* Draw all full runs */
339 for (i=0; i<(YDelta-1); i++)
341 RunLength = WholeStep; /* run is at least this long */
343 /* Advance the error term and add an extra pixel if the error term so indicates */
344 if ((ErrorTerm += AdjUp) > 0)
347 ErrorTerm -= AdjDown; /* reset the error term */
349 /* Draw this scan line's run */
351 //if ( *source != Transparency_color )
352 rep_stosb(dest, RunLength, *source );
358 /* Draw the final run of pixels */
359 //if ( *source != Transparency_color )
360 rep_stosb(dest, FinalPixelCount, *source );
368 void rls_stretch_scanline_setup( int XDelta, int YDelta )
370 scale_trans_color = Transparency_color & 0xFF;
371 scale_ydelta_minus_1 = YDelta - 1;
374 /* Minimum # of pixels in a run in this line */
375 scale_whole_step = XDelta / YDelta;
377 /* Error term adjust each time Y steps by 1; used to tell when one
378 extra pixel should be drawn as part of a run, to account for
379 fractional steps along the X axis per 1-pixel steps along Y */
380 scale_adj_up = (XDelta % YDelta) * 2;
382 /* Error term adjust when the error term turns over, used to factor
383 out the X step made at that time */
384 scale_adj_down = YDelta * 2;
386 /* Initial error term; reflects an initial step of 0.5 along the Y
388 scale_error_term = (XDelta % YDelta) - (YDelta * 2);
390 /* The initial and last runs are partial, because Y advances only 0.5
391 for these runs, rather than 1. Divide one full run, plus the
392 initial pixel, between the initial and last runs */
393 scale_initial_pixel_count = (scale_whole_step / 2) + 1;
394 scale_final_pixel_count = scale_initial_pixel_count;
396 /* If the basic run length is even and there's no fractional
397 advance, we have one pixel that could go to either the initial
398 or last partial run, which we'll arbitrarily allocate to the
400 if ((scale_adj_up == 0) && ((scale_whole_step & 0x01) == 0))
402 scale_initial_pixel_count--;
404 /* If there're an odd number of pixels per run, we have 1 pixel that can't
405 be allocated to either the initial or last partial run, so we'll add 0.5
406 to error term so this pixel will be handled by the normal full-run loop */
407 if ((scale_whole_step & 0x01) != 0)
409 scale_error_term += YDelta;