2 Copyright (C) Intel Corp. 2006. All Rights Reserved.
3 Intel funded Tungsten Graphics (http://www.tungstengraphics.com) to
4 develop this 3D driver.
6 Permission is hereby granted, free of charge, to any person obtaining
7 a copy of this software and associated documentation files (the
8 "Software"), to deal in the Software without restriction, including
9 without limitation the rights to use, copy, modify, merge, publish,
10 distribute, sublicense, and/or sell copies of the Software, and to
11 permit persons to whom the Software is furnished to do so, subject to
12 the following conditions:
14 The above copyright notice and this permission notice (including the
15 next paragraph) shall be included in all copies or substantial
16 portions of the Software.
18 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
19 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
21 IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
22 LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
23 OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
24 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
26 **********************************************************************/
29 * Keith Whitwell <keith@tungstengraphics.com>
32 #include "main/glheader.h"
33 #include "main/macros.h"
34 #include "main/enums.h"
35 #include "program/program.h"
37 #include "intel_batchbuffer.h"
39 #include "brw_defines.h"
40 #include "brw_context.h"
46 static void brw_clip_line_alloc_regs( struct brw_clip_compile
*c
)
48 struct intel_context
*intel
= &c
->func
.brw
->intel
;
51 /* Register usage is static, precompute here:
53 c
->reg
.R0
= retype(brw_vec8_grf(i
, 0), BRW_REGISTER_TYPE_UD
); i
++;
55 if (c
->key
.nr_userclip
) {
56 c
->reg
.fixed_planes
= brw_vec4_grf(i
, 0);
57 i
+= (6 + c
->key
.nr_userclip
+ 1) / 2;
59 c
->prog_data
.curb_read_length
= (6 + c
->key
.nr_userclip
+ 1) / 2;
62 c
->prog_data
.curb_read_length
= 0;
65 /* Payload vertices plus space for more generated vertices:
67 for (j
= 0; j
< 4; j
++) {
68 c
->reg
.vertex
[j
] = brw_vec4_grf(i
, 0);
72 c
->reg
.t
= brw_vec1_grf(i
, 0);
73 c
->reg
.t0
= brw_vec1_grf(i
, 1);
74 c
->reg
.t1
= brw_vec1_grf(i
, 2);
75 c
->reg
.planemask
= retype(brw_vec1_grf(i
, 3), BRW_REGISTER_TYPE_UD
);
76 c
->reg
.plane_equation
= brw_vec4_grf(i
, 4);
79 c
->reg
.dp0
= brw_vec1_grf(i
, 0); /* fixme - dp4 will clobber r.1,2,3 */
80 c
->reg
.dp1
= brw_vec1_grf(i
, 4);
83 if (!c
->key
.nr_userclip
) {
84 c
->reg
.fixed_planes
= brw_vec8_grf(i
, 0);
88 if (intel
->needs_ff_sync
) {
89 c
->reg
.ff_sync
= retype(brw_vec1_grf(i
, 0), BRW_REGISTER_TYPE_UD
);
96 c
->prog_data
.urb_read_length
= c
->nr_regs
; /* ? */
97 c
->prog_data
.total_grf
= i
;
102 /* Line clipping, more or less following the following algorithm:
104 * for (p=0;p<MAX_PLANES;p++) {
105 * if (clipmask & (1 << p)) {
106 * GLfloat dp0 = DOTPROD( vtx0, plane[p] );
107 * GLfloat dp1 = DOTPROD( vtx1, plane[p] );
109 * if (IS_NEGATIVE(dp1)) {
110 * GLfloat t = dp1 / (dp1 - dp0);
111 * if (t > t1) t1 = t;
113 * GLfloat t = dp0 / (dp0 - dp1);
114 * if (t > t0) t0 = t;
117 * if (t0 + t1 >= 1.0)
122 * interp( ctx, newvtx0, vtx0, vtx1, t0 );
123 * interp( ctx, newvtx1, vtx1, vtx0, t1 );
126 static void clip_and_emit_line( struct brw_clip_compile
*c
)
128 struct brw_compile
*p
= &c
->func
;
129 struct brw_context
*brw
= p
->brw
;
130 struct brw_indirect vtx0
= brw_indirect(0, 0);
131 struct brw_indirect vtx1
= brw_indirect(1, 0);
132 struct brw_indirect newvtx0
= brw_indirect(2, 0);
133 struct brw_indirect newvtx1
= brw_indirect(3, 0);
134 struct brw_indirect plane_ptr
= brw_indirect(4, 0);
135 struct brw_instruction
*plane_loop
;
136 struct brw_reg v1_null_ud
= retype(vec1(brw_null_reg()), BRW_REGISTER_TYPE_UD
);
138 brw_MOV(p
, get_addr_reg(vtx0
), brw_address(c
->reg
.vertex
[0]));
139 brw_MOV(p
, get_addr_reg(vtx1
), brw_address(c
->reg
.vertex
[1]));
140 brw_MOV(p
, get_addr_reg(newvtx0
), brw_address(c
->reg
.vertex
[2]));
141 brw_MOV(p
, get_addr_reg(newvtx1
), brw_address(c
->reg
.vertex
[3]));
142 brw_MOV(p
, get_addr_reg(plane_ptr
), brw_clip_plane0_address(c
));
144 /* Note: init t0, t1 together:
146 brw_MOV(p
, vec2(c
->reg
.t0
), brw_imm_f(0));
148 brw_clip_init_planes(c
);
149 brw_clip_init_clipmask(c
);
151 /* -ve rhw workaround */
152 if (brw
->has_negative_rhw_bug
) {
153 brw_set_conditionalmod(p
, BRW_CONDITIONAL_NZ
);
154 brw_AND(p
, brw_null_reg(), get_element_ud(c
->reg
.R0
, 2),
156 brw_OR(p
, c
->reg
.planemask
, c
->reg
.planemask
, brw_imm_ud(0x3f));
159 brw_set_predicate_control(p
, BRW_PREDICATE_NONE
);
161 plane_loop
= brw_DO(p
, BRW_EXECUTE_1
);
163 /* if (planemask & 1)
165 brw_set_conditionalmod(p
, BRW_CONDITIONAL_NZ
);
166 brw_AND(p
, v1_null_ud
, c
->reg
.planemask
, brw_imm_ud(1));
168 brw_IF(p
, BRW_EXECUTE_1
);
170 if (c
->key
.nr_userclip
)
171 brw_MOV(p
, c
->reg
.plane_equation
, deref_4f(plane_ptr
, 0));
173 brw_MOV(p
, c
->reg
.plane_equation
, deref_4b(plane_ptr
, 0));
175 /* dp = DP4(vtx->position, plane)
177 brw_DP4(p
, vec4(c
->reg
.dp0
), deref_4f(vtx0
, c
->offset
[VERT_RESULT_HPOS
]), c
->reg
.plane_equation
);
179 /* if (IS_NEGATIVE(dp1))
181 brw_set_conditionalmod(p
, BRW_CONDITIONAL_L
);
182 brw_DP4(p
, vec4(c
->reg
.dp1
), deref_4f(vtx1
, c
->offset
[VERT_RESULT_HPOS
]), c
->reg
.plane_equation
);
183 brw_IF(p
, BRW_EXECUTE_1
);
186 * Both can be negative on GM965/G965 due to RHW workaround
187 * if so, this object should be rejected.
189 if (brw
->has_negative_rhw_bug
) {
190 brw_CMP(p
, vec1(brw_null_reg()), BRW_CONDITIONAL_LE
, c
->reg
.dp0
, brw_imm_f(0.0));
191 brw_IF(p
, BRW_EXECUTE_1
);
193 brw_clip_kill_thread(c
);
198 brw_ADD(p
, c
->reg
.t
, c
->reg
.dp1
, negate(c
->reg
.dp0
));
199 brw_math_invert(p
, c
->reg
.t
, c
->reg
.t
);
200 brw_MUL(p
, c
->reg
.t
, c
->reg
.t
, c
->reg
.dp1
);
202 brw_CMP(p
, vec1(brw_null_reg()), BRW_CONDITIONAL_G
, c
->reg
.t
, c
->reg
.t1
);
203 brw_MOV(p
, c
->reg
.t1
, c
->reg
.t
);
204 brw_set_predicate_control(p
, BRW_PREDICATE_NONE
);
208 /* Coming back in. We know that both cannot be negative
209 * because the line would have been culled in that case.
212 /* If both are positive, do nothing */
213 /* Only on GM965/G965 */
214 if (brw
->has_negative_rhw_bug
) {
215 brw_CMP(p
, vec1(brw_null_reg()), BRW_CONDITIONAL_L
, c
->reg
.dp0
, brw_imm_f(0.0));
216 brw_IF(p
, BRW_EXECUTE_1
);
220 brw_ADD(p
, c
->reg
.t
, c
->reg
.dp0
, negate(c
->reg
.dp1
));
221 brw_math_invert(p
, c
->reg
.t
, c
->reg
.t
);
222 brw_MUL(p
, c
->reg
.t
, c
->reg
.t
, c
->reg
.dp0
);
224 brw_CMP(p
, vec1(brw_null_reg()), BRW_CONDITIONAL_G
, c
->reg
.t
, c
->reg
.t0
);
225 brw_MOV(p
, c
->reg
.t0
, c
->reg
.t
);
226 brw_set_predicate_control(p
, BRW_PREDICATE_NONE
);
229 if (brw
->has_negative_rhw_bug
) {
239 brw_ADD(p
, get_addr_reg(plane_ptr
), get_addr_reg(plane_ptr
), brw_clip_plane_stride(c
));
241 /* while (planemask>>=1) != 0
243 brw_set_conditionalmod(p
, BRW_CONDITIONAL_NZ
);
244 brw_SHR(p
, c
->reg
.planemask
, c
->reg
.planemask
, brw_imm_ud(1));
246 brw_WHILE(p
, plane_loop
);
248 brw_ADD(p
, c
->reg
.t
, c
->reg
.t0
, c
->reg
.t1
);
249 brw_CMP(p
, vec1(brw_null_reg()), BRW_CONDITIONAL_L
, c
->reg
.t
, brw_imm_f(1.0));
250 brw_IF(p
, BRW_EXECUTE_1
);
252 brw_clip_interp_vertex(c
, newvtx0
, vtx0
, vtx1
, c
->reg
.t0
, GL_FALSE
);
253 brw_clip_interp_vertex(c
, newvtx1
, vtx1
, vtx0
, c
->reg
.t1
, GL_FALSE
);
255 brw_clip_emit_vue(c
, newvtx0
, 1, 0, (_3DPRIM_LINESTRIP
<< 2) | R02_PRIM_START
);
256 brw_clip_emit_vue(c
, newvtx1
, 0, 1, (_3DPRIM_LINESTRIP
<< 2) | R02_PRIM_END
);
259 brw_clip_kill_thread(c
);
264 void brw_emit_line_clip( struct brw_clip_compile
*c
)
266 brw_clip_line_alloc_regs(c
);
267 brw_clip_init_ff_sync(c
);
269 if (c
->key
.do_flat_shading
) {
271 brw_clip_copy_colors(c
, 1, 0);
273 brw_clip_copy_colors(c
, 0, 1);
276 clip_and_emit_line(c
);