2 * Mesa 3-D graphics library
5 * Copyright (C) 1999-2005 Brian Paul All Rights Reserved.
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the "Software"),
9 * to deal in the Software without restriction, including without limitation
10 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
11 * and/or sell copies of the Software, and to permit persons to whom the
12 * Software is furnished to do so, subject to the following conditions:
14 * The above copyright notice and this permission notice shall be included
15 * in all copies or substantial portions of the Software.
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
18 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
21 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
22 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
25 /* Vertices are just an array of floats, with all the attributes
26 * packed. We currently assume a layout like:
28 * attr[0][0..3] - window position
29 * attr[1..n][0..3] - remaining attributes.
31 * Attributes are assumed to be 4 floats wide but are packed so that
32 * all the enabled attributes run contiguously.
37 #include "sp_context.h"
38 #include "sp_headers.h"
42 const struct setup_coefficient
*coef
; /**< will point to quad->coef */
44 GLfloat attr
[FRAG_ATTRIB_MAX
][4][QUAD_SIZE
];
49 * Compute quad's attributes values, as constants (GL_FLAT shading).
51 static INLINE
void cinterp( struct exec_machine
*exec
,
57 for (j
= 0; j
< QUAD_SIZE
; j
++) {
58 exec
->attr
[attrib
][i
][j
] = exec
->coef
[attrib
].a0
[i
];
64 * Compute quad's attribute values by linear interpolation.
68 * INPUT[attr] = MAD COEF_A0[attr], COEF_DADX[attr], INPUT_WPOS.xxxx
69 * INPUT[attr] = MAD INPUT[attr], COEF_DADY[attr], INPUT_WPOS.yyyy
71 static INLINE
void linterp( struct exec_machine
*exec
,
77 for (j
= 0; j
< QUAD_SIZE
; j
++) {
78 const GLfloat x
= exec
->attr
[FRAG_ATTRIB_WPOS
][0][j
];
79 const GLfloat y
= exec
->attr
[FRAG_ATTRIB_WPOS
][1][j
];
80 exec
->attr
[attrib
][i
][j
] = (exec
->coef
[attrib
].a0
[i
] +
81 exec
->coef
[attrib
].dadx
[i
] * x
+
82 exec
->coef
[attrib
].dady
[i
] * y
);
88 * Compute quad's attribute values by linear interpolation with
89 * perspective correction.
93 * INPUT[attr] = MAD COEF_A0[attr], COEF_DADX[attr], INPUT_WPOS.xxxx
94 * INPUT[attr] = MAD INPUT[attr], COEF_DADY[attr], INPUT_WPOS.yyyy
95 * INPUT[attr] = MUL INPUT[attr], INPUT_WPOS.wwww
97 * (Or should that be 1/w ???)
99 static INLINE
void pinterp( struct exec_machine
*exec
,
105 for (j
= 0; j
< QUAD_SIZE
; j
++) {
106 const GLfloat x
= exec
->attr
[FRAG_ATTRIB_WPOS
][0][j
];
107 const GLfloat y
= exec
->attr
[FRAG_ATTRIB_WPOS
][1][j
];
108 const GLfloat invW
= exec
->attr
[FRAG_ATTRIB_WPOS
][3][j
];
109 exec
->attr
[attrib
][i
][j
] = ((exec
->coef
[attrib
].a0
[i
] +
110 exec
->coef
[attrib
].dadx
[i
] * x
+
111 exec
->coef
[attrib
].dady
[i
] * y
) * invW
);
117 /* This should be done by the fragment shader execution unit (code
118 * generated from the decl instructions). Do it here for now.
121 shade_quad( struct quad_stage
*qs
, struct quad_header
*quad
)
123 struct softpipe_context
*softpipe
= qs
->softpipe
;
124 struct exec_machine exec
;
125 GLfloat fx
= quad
->x0
;
126 GLfloat fy
= quad
->y0
;
128 GLboolean need_z
= softpipe
->depth_test
.enabled
; /* XXX hack */
130 exec
.coef
= quad
->coef
;
134 exec
.attr
[FRAG_ATTRIB_WPOS
][0][0] = fx
;
135 exec
.attr
[FRAG_ATTRIB_WPOS
][0][1] = fx
+ 1.0;
136 exec
.attr
[FRAG_ATTRIB_WPOS
][0][2] = fx
;
137 exec
.attr
[FRAG_ATTRIB_WPOS
][0][3] = fx
+ 1.0;
139 exec
.attr
[FRAG_ATTRIB_WPOS
][1][0] = fy
;
140 exec
.attr
[FRAG_ATTRIB_WPOS
][1][1] = fy
;
141 exec
.attr
[FRAG_ATTRIB_WPOS
][1][2] = fy
+ 1.0;
142 exec
.attr
[FRAG_ATTRIB_WPOS
][1][3] = fy
+ 1.0;
144 /* Z and W are done by linear interpolation:
145 * XXX we'll probably have to use integers for Z
147 if (/*softpipe->*/need_z
) {
148 linterp(&exec
, 0, 2); /* attr[0].z */
151 if (softpipe
->need_w
) {
152 linterp(&exec
, 0, 3); /* attr[0].w */
153 // invert(&exec, 0, 3);
156 /* Interpolate all the remaining attributes. This will get pushed
157 * into the fragment program's responsibilities at some point.
159 for (i
= 1; i
< quad
->nr_attrs
; i
++) {
161 for (j
= 0; j
< NUM_CHANNELS
; j
++)
162 linterp(&exec
, i
, j
);
164 switch (quad
->interp
[i
]) {
165 case INTERP_CONSTANT
:
166 for (j
= 0; j
< NUM_CHANNELS
; j
++)
167 cinterp(&exec
, i
, j
);
171 for (j
= 0; j
< NUM_CHANNELS
; j
++)
172 linterp(&exec
, i
, j
);
175 case INTERP_PERSPECTIVE
:
176 for (j
= 0; j
< NUM_CHANNELS
; j
++)
177 pinterp(&exec
, i
, j
);
184 softpipe
->run_fs( tri
->fp
, quad
, &tri
->outputs
);
187 GLuint attr
= softpipe
->fp_attr_to_slot
[FRAG_ATTRIB_COL0
];
190 memcpy(quad
->outputs
.color
,
192 sizeof(quad
->outputs
.color
));
195 quad
->outputs
.depth
[0] = exec
.attr
[0][2][0];
196 quad
->outputs
.depth
[1] = exec
.attr
[0][2][1];
197 quad
->outputs
.depth
[2] = exec
.attr
[0][2][2];
198 quad
->outputs
.depth
[3] = exec
.attr
[0][2][3];
203 /* shader may cull fragments */
205 qs
->next
->run(qs
->next
, quad
);
210 struct quad_stage
*sp_quad_shade_stage( struct softpipe_context
*softpipe
)
212 struct quad_stage
*stage
= CALLOC_STRUCT(quad_stage
);
214 stage
->softpipe
= softpipe
;
215 stage
->run
= shade_quad
;