Pete`s Messageboard Forum - OGL2 shaders - 2xSaI GLSL shader

Needs a pixel shader 3.0 capable graphics card (ie. Gf 6600 or better, radeon x1300 or better). Same counts for the SuperEagle and Super2xSaI GLSL shaders posted on this board (by myself).

Some advice. Theese shaders are preety (and) slow ones, so i would use them only for double scaling (usualy in 640x480).

- 01.5.2007: 6-8% speedup.
- 09.5.2007: another 20% speedup (+5% afternoon

vertex file:

Code:
1:
2:
3:
4:
5:
6:
7:
8:
9:
10:
11:
12:
13:
14:
15:
16:
17:
18:
19:
20:
21:
22:
23:
24:
25:
26:
27:
28:
29:
30:
31:
32:
33:
34:
35:
36:
37:
38:
39:
40:
41:
42:
43:
44:
45:
46:
47:
48:
49:
50:
51:
52:
53:
54:
55:
56:
57:
58:
59:
60:
61:
62:
63:
64:
65:
66:
67:
68:
69:
70:
71:
72:
73:
74:
75:
76:
77:
78:
79:
80:
81:
82:
83:
84:
85:
86:
87:
88:
89:
90:
91:
92:
93:
94:
95:
96:
97:
98:
99:
100:
101:
102:
103:
104:
105:
106:
107:
108:
109:
110:
111:
112:
113:
114:
115:
116:
117:
118:
119:
120:
121:
122:
123:
124:
125:
126:
127:
128:
129:
130:
131:
132:
133:
134:
135:
136:
137:
138:
139:
140:
141:
142:
143:
144:



/*
2xSaI GLSL shader

- Copyright (C) 2007 guest(r) - guest.r@gmail.com

- License: GNU-GPL


The 2xSaI algorithm

- Copyright (c) 1999-2001 by Derek Liauw Kie Fa.

*/


const vec3 dt = vec3(65536.0,256.0,1.0);



float GET_RESULT(float A, float B, float C, float D)
{
return (sign(abs(A-C)+abs(A-D)) - sign(abs(B-C)+abs(B-D)));
}


float reduce(vec3 color)
{
return dot(color,dt);
}


uniform vec4 OGL2Size;
uniform vec4 OGL2InvSize;
uniform sampler2D OGL2Texture;

void main()
{

// Calculating texel coordinates

vec2 OGL2Pos = gl_TexCoord[0].xy*OGL2Size.xy;
vec2 fp = fract(OGL2Pos);
vec2 g1 = vec2( OGL2InvSize.x,OGL2InvSize.y);
vec2 g2 = vec2(-OGL2InvSize.x,OGL2InvSize.y);

if (fp.x >= 0.50 && fp.y < 0.50) g2*=-1.0;

vec2 pC4 = floor(OGL2Pos)/OGL2Size.xy;
vec2 pC8 = pC4 + g1;
vec2 pC0 = pC4 - g1;

vec2 p04 = pC4 - 0.5*g1;
vec2 pC3 = p04 + 0.5*g2;
vec2 pC1 = pC3 - g2;
vec2 pC5 = pC1 + g1;
vec2 pC7 = pC3 + g1;


// Reading the texels

vec3 C0 = texture2D(OGL2Texture,pC0 ).xyz;
vec3 C1 = texture2D(OGL2Texture,pC1 ).xyz;
vec3 C2 = texture2D(OGL2Texture,pC4-g2).xyz;
vec3 C3 = texture2D(OGL2Texture,pC3 ).xyz;
vec3 C4 = texture2D(OGL2Texture,pC4 ).xyz;
vec3 C5 = texture2D(OGL2Texture,pC5 ).xyz;
vec3 D4 = texture2D(OGL2Texture,pC8-g2).xyz;
vec3 C6 = texture2D(OGL2Texture,pC4+g2).xyz;
vec3 C7 = texture2D(OGL2Texture,pC7 ).xyz;
vec3 C8 = texture2D(OGL2Texture,pC8 ).xyz;
vec3 D5 = texture2D(OGL2Texture,pC5+g1).xyz;
vec3 D0 = texture2D(OGL2Texture,pC7+g2).xyz;
vec3 D1 = texture2D(OGL2Texture,pC8+g2).xyz;
vec3 D2 = texture2D(OGL2Texture,pC7+g1).xyz;
vec3 p10,p11;

float c0 = reduce(C0);float c1 = reduce(C1);
float c2 = reduce(C2);float c3 = reduce(C3);
float c4 = reduce(C4);float c5 = reduce(C5);
float c6 = reduce(C6);float c7 = reduce(C7);
float c8 = reduce(C8);float d0 = reduce(D0);
float d1 = reduce(D1);float d2 = reduce(D2);
float d4 = reduce(D4);float d5 = reduce(D5);


/* SaI code */
/* Copied from the Dosbox source code */
/* Copyright (C) 2002-2007 The DOSBox Team */
/* License: GNU-GPL */
/* Adapted by guest(r) on 20.4 and 9.5. 2007 */

if (c4 == c8) {
if (c5 != c7) {
if (((c4 == c3)&&(c7 == d2))\|\|((c4 == c5)&&(c4 == c6)&&(c3 != c7)&&(c7 == d0))) {
p10 = C4;
} else {
p10 = 0.5*(C4+C7);
}
p11 = C4;
} else {
if (c4 == c5) {
p10 = C4;
p11 = C4;
} else {
float r;
r = GET_RESULT(c4,c5,c3,c1);
r -= GET_RESULT(c5,c4,d4,c2);
r -= GET_RESULT(c5,c4,c6,d1);
r += GET_RESULT(c4,c5,d5,d2);
if (r > 0.0) p11 = C4;
else if (r < 0.0) p11 = C5;
else p11 = 0.25*(C4+C5+C7+C8);
p10 = 0.5*(C4+C7);
}
}
} else
if (c5 == c7) {
if (((c7 == c6)&&(c4 == c2))\|\|((c7 == c3)&&(c7 == c8)&&(c4 != c6)&&(c4 == c0))) {
p10 = C7;
} else {
p10 = 0.5*(C4+C7);
}
p11 = C5;
} else {
p11 = 0.25*(C4+C5+C7+C8);

if ((c4 == c5)&&(c4 == c6)&&(c3 != c7)&&(c7 == d0)) {
p10 = C4;
} else if ((c7 == c3)&&(c7 == c8)&&(c4 != c6)&&(c4 == c0)) {
p10 = C7;
} else {
p10 = 0.5*(C4+C7);
}
}

// Distributing the final products

if (fp.x >= 0.5 && fp.y >= 0.5) gl_FragColor.xyz = p11; else
if (fp.x < 0.5 && fp.y < 0.5) gl_FragColor.xyz = C4; else
gl_FragColor.xyz = p10;
}

Code:
1:
2:
3:
4:
5:
6:
7:
8:
9:
10:
11:
12:
13:
14:
15:
16:
17:
18:
19:
20:
21:
22:
23:
24:
25:
26:
27:
28:
29:
30:
31:
32:
33:
34:
35:
36:
37:
38:
39:
40:
41:
42:
43:
44:
45:
46:
47:
48:
49:
50:
51:
52:
53:
54:
55:
56:
57:
58:
59:
60:
61:
62:
63:
64:
65:
66:
67:
68:
69:
70:
71:
72:
73:
74:
75:
76:
77:
78:
79:
80:
81:
82:
83:
84:
85:
86:
87:
88:
89:
90:
91:
92:
93:
94:
95:
96:
97:
98:
99:
100:
101:
102:
103:
104:
105:
106:
107:
108:
109:
110:
111:
112:
113:
114:
115:
116:
117:
118:
119:
120:
121:
122:
123:
124:
125:
126:
127:
128:
129:
130:
131:
132:
133:
134:
135:
136:
137:
138:
139:
140:
141:
142:
143:
144:
145:
146:
147:
148:
149:
150:
151:
152:
153:
154:
155:
156:
157:
158:
159:
160:
161:
162:
163:
164:
165:
166:
167:
168:
169:
170:
171:
172:
173:
174:
175:
176:
177:
178:
179:
180:
181:
182:
183:
184:
185:
186:
187:
188:
189:
190:
191:
192:
193:
194:
195:
196:
197:
198:
199:
200:
201:
202:
203:
204:
205:
206:
207:
208:
209:
210:
211:
212:
213:
214:
215:
216:
217:
218:
219:
220:
221:
222:
223:
224:
225:
226:
227:
228:
229:
230:
231:
232:
233:
234:
235:
236:
237:
238:
239:
240:
241:
242:
243:
244:
245:
246:
247:
248:
249:
250:
251:
252:
253:
254:
255:
256:
257:
258:
259:
260:
261:
262:
263:
264:
265:
266:
267:
268:
269:
270:
271:
272:
273:
274:
275:
276:
277:
278:
279:
280:
281:
282:
283:
284:
285:
286:
287:
288:
289:
290:
291:
292:
293:
294:
295:
296:
297:
298:
299:
300:
301:
302:
303:
304:
305:
306:
307:
308:
309:
310:
311:
312:
313:
314:
315:
316:
317:
318:
319:
320:
321:
322:
323:
324:
325:
326:
327:
328:
329:
330:
331:
332:
333:
334:
335:
336:
337:
338:
339:
340:
341:
342:



GNU GENERAL PUBLIC LICENSE
Version 2, June 1991

Copyright (C) 1989, 1991 Free Software Foundation, Inc.
675 Mass Ave, Cambridge, MA 02139, USA
Everyone is permitted to copy and distribute verbatim copies
of this license document, but changing it is not allowed.

Preamble

The licenses for most software are designed to take away your
freedom to share and change it. By contrast, the GNU General Public
License is intended to guarantee your freedom to share and change free
software--to make sure the software is free for all its users. This
General Public License applies to most of the Free Software
Foundation's software and to any other program whose authors commit to
using it. (Some other Free Software Foundation software is covered by
the GNU Library General Public License instead.) You can apply it to
your programs, too.

When we speak of free software, we are referring to freedom, not
price. Our General Public Licenses are designed to make sure that you
have the freedom to distribute copies of free software (and charge for
this service if you wish), that you receive source code or can get it
if you want it, that you can change the software or use pieces of it
in new free programs; and that you know you can do these things.

To protect your rights, we need to make restrictions that forbid
anyone to deny you these rights or to ask you to surrender the rights.
These restrictions translate to certain responsibilities for you if you
distribute copies of the software, or if you modify it.

For example, if you distribute copies of such a program, whether
gratis or for a fee, you must give the recipients all the rights that
you have. You must make sure that they, too, receive or can get the
source code. And you must show them these terms so they know their
rights.

We protect your rights with two steps: (1) copyright the software, and
(2) offer you this license which gives you legal permission to copy,
distribute and/or modify the software.

Also, for each author's protection and ours, we want to make certain
that everyone understands that there is no warranty for this free
software. If the software is modified by someone else and passed on, we
want its recipients to know that what they have is not the original, so
that any problems introduced by others will not reflect on the original
authors' reputations.

Finally, any free program is threatened constantly by software
patents. We wish to avoid the danger that redistributors of a free
program will individually obtain patent licenses, in effect making the
program proprietary. To prevent this, we have made it clear that any
patent must be licensed for everyone's free use or not licensed at all.

The precise terms and conditions for copying, distribution and
modification follow.

GNU GENERAL PUBLIC LICENSE
TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION

0. This License applies to any program or other work which contains
a notice placed by the copyright holder saying it may be distributed
under the terms of this General Public License. The "Program", below,
refers to any such program or work, and a "work based on the Program"
means either the Program or any derivative work under copyright law:
that is to say, a work containing the Program or a portion of it,
either verbatim or with modifications and/or translated into another
language. (Hereinafter, translation is included without limitation in
the term "modification".) Each licensee is addressed as "you".

Activities other than copying, distribution and modification are not
covered by this License; they are outside its scope. The act of
running the Program is not restricted, and the output from the Program
is covered only if its contents constitute a work based on the
Program (independent of having been made by running the Program).
Whether that is true depends on what the Program does.

1. You may copy and distribute verbatim copies of the Program's
source code as you receive it, in any medium, provided that you
conspicuously and appropriately publish on each copy an appropriate
copyright notice and disclaimer of warranty; keep intact all the
notices that refer to this License and to the absence of any warranty;
and give any other recipients of the Program a copy of this License
along with the Program.

You may charge a fee for the physical act of transferring a copy, and
you may at your option offer warranty protection in exchange for a fee.

2. You may modify your copy or copies of the Program or any portion
of it, thus forming a work based on the Program, and copy and
distribute such modifications or work under the terms of Section 1
above, provided that you also meet all of these conditions:

a) You must cause the modified files to carry prominent notices
stating that you changed the files and the date of any change.

b) You must cause any work that you distribute or publish, that in
whole or in part contains or is derived from the Program or any
part thereof, to be licensed as a whole at no charge to all third
parties under the terms of this License.

c) If the modified program normally reads commands interactively
when run, you must cause it, when started running for such
interactive use in the most ordinary way, to print or display an
announcement including an appropriate copyright notice and a
notice that there is no warranty (or else, saying that you provide
a warranty) and that users may redistribute the program under
these conditions, and telling the user how to view a copy of this
License. (Exception: if the Program itself is interactive but
does not normally print such an announcement, your work based on
the Program is not required to print an announcement.)

These requirements apply to the modified work as a whole. If
identifiable sections of that work are not derived from the Program,
and can be reasonably considered independent and separate works in
themselves, then this License, and its terms, do not apply to those
sections when you distribute them as separate works. But when you
distribute the same sections as part of a whole which is a work based
on the Program, the distribution of the whole must be on the terms of
this License, whose permissions for other licensees extend to the
entire whole, and thus to each and every part regardless of who wrote it.

Thus, it is not the intent of this section to claim rights or contest
your rights to work written entirely by you; rather, the intent is to
exercise the right to control the distribution of derivative or
collective works based on the Program.

In addition, mere aggregation of another work not based on the Program
with the Program (or with a work based on the Program) on a volume of
a storage or distribution medium does not bring the other work under
the scope of this License.

3. You may copy and distribute the Program (or a work based on it,
under Section 2) in object code or executable form under the terms of
Sections 1 and 2 above provided that you also do one of the following:

a) Accompany it with the complete corresponding machine-readable
source code, which must be distributed under the terms of Sections
1 and 2 above on a medium customarily used for software interchange; or,

b) Accompany it with a written offer, valid for at least three
years, to give any third party, for a charge no more than your
cost of physically performing source distribution, a complete
machine-readable copy of th

Pete´s Messageboard... No ISO/BIOS requests!

2xSaI GLSL shader