2 * Mesa 3-D graphics library
5 * Copyright (C) 1999-2007 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 #include "main/glheader.h"
26 #include "main/colormac.h"
27 #include "main/context.h"
28 #include "main/texstate.h"
29 #include "shader/prog_instruction.h"
31 #include "s_fragprog.h"
36 * Fetch a texel with given lod.
37 * Called via machine->FetchTexelLod()
40 fetch_texel_lod( GLcontext
*ctx
, const GLfloat texcoord
[4], GLfloat lambda
,
41 GLuint unit
, GLfloat color
[4] )
44 SWcontext
*swrast
= SWRAST_CONTEXT(ctx
);
45 const struct gl_texture_object
*texObj
= ctx
->Texture
.Unit
[unit
]._Current
;
48 lambda
= CLAMP(lambda
, texObj
->MinLod
, texObj
->MaxLod
);
50 /* XXX use a float-valued TextureSample routine here!!! */
51 swrast
->TextureSample
[unit
](ctx
, texObj
, 1, (const GLfloat (*)[4]) texcoord
,
53 color
[0] = CHAN_TO_FLOAT(rgba
[0]);
54 color
[1] = CHAN_TO_FLOAT(rgba
[1]);
55 color
[2] = CHAN_TO_FLOAT(rgba
[2]);
56 color
[3] = CHAN_TO_FLOAT(rgba
[3]);
61 * Fetch a texel with the given partial derivatives to compute a level
62 * of detail in the mipmap.
63 * Called via machine->FetchTexelDeriv()
66 fetch_texel_deriv( GLcontext
*ctx
, const GLfloat texcoord
[4],
67 const GLfloat texdx
[4], const GLfloat texdy
[4],
68 GLfloat lodBias
, GLuint unit
, GLfloat color
[4] )
70 SWcontext
*swrast
= SWRAST_CONTEXT(ctx
);
71 const struct gl_texture_object
*texObj
= ctx
->Texture
.Unit
[unit
]._Current
;
76 const struct gl_texture_image
*texImg
= texObj
->Image
[0][texObj
->BaseLevel
];
77 const GLfloat texW
= (GLfloat
) texImg
->WidthScale
;
78 const GLfloat texH
= (GLfloat
) texImg
->HeightScale
;
80 lambda
= _swrast_compute_lambda(texdx
[0], texdy
[0], /* ds/dx, ds/dy */
81 texdx
[1], texdy
[1], /* dt/dx, dt/dy */
82 texdx
[3], texdy
[2], /* dq/dx, dq/dy */
84 texcoord
[0], texcoord
[1], texcoord
[3],
85 1.0F
/ texcoord
[3]) + lodBias
;
87 lambda
= CLAMP(lambda
, texObj
->MinLod
, texObj
->MaxLod
);
90 swrast
->TextureSample
[unit
](ctx
, texObj
, 1, (const GLfloat (*)[4]) texcoord
,
92 color
[0] = CHAN_TO_FLOAT(rgba
[0]);
93 color
[1] = CHAN_TO_FLOAT(rgba
[1]);
94 color
[2] = CHAN_TO_FLOAT(rgba
[2]);
95 color
[3] = CHAN_TO_FLOAT(rgba
[3]);
100 * Initialize the virtual fragment program machine state prior to running
101 * fragment program on a fragment. This involves initializing the input
102 * registers, condition codes, etc.
103 * \param machine the virtual machine state to init
104 * \param program the fragment program we're about to run
105 * \param span the span of pixels we'll operate on
106 * \param col which element (column) of the span we'll operate on
109 init_machine(GLcontext
*ctx
, struct gl_program_machine
*machine
,
110 const struct gl_fragment_program
*program
,
111 const SWspan
*span
, GLuint col
)
113 if (program
->Base
.Target
== GL_FRAGMENT_PROGRAM_NV
) {
114 /* Clear temporary registers (undefined for ARB_f_p) */
115 _mesa_bzero(machine
->Temporaries
,
116 MAX_PROGRAM_TEMPS
* 4 * sizeof(GLfloat
));
119 /* Setup pointer to input attributes */
120 machine
->Attribs
= span
->array
->attribs
;
122 machine
->DerivX
= (GLfloat (*)[4]) span
->attrStepX
;
123 machine
->DerivY
= (GLfloat (*)[4]) span
->attrStepY
;
124 machine
->NumDeriv
= FRAG_ATTRIB_MAX
;
126 machine
->Samplers
= program
->Base
.SamplerUnits
;
128 /* if running a GLSL program (not ARB_fragment_program) */
129 if (ctx
->Shader
.CurrentProgram
) {
130 /* Store front/back facing value in register FOGC.Y */
131 machine
->Attribs
[FRAG_ATTRIB_FOGC
][col
][1] = 1.0 - span
->facing
;
132 /* Note FOGC.ZW is gl_PointCoord if drawing a sprite */
135 machine
->CurElement
= col
;
137 /* init condition codes */
138 machine
->CondCodes
[0] = COND_EQ
;
139 machine
->CondCodes
[1] = COND_EQ
;
140 machine
->CondCodes
[2] = COND_EQ
;
141 machine
->CondCodes
[3] = COND_EQ
;
143 /* init call stack */
144 machine
->StackDepth
= 0;
146 machine
->FetchTexelLod
= fetch_texel_lod
;
147 machine
->FetchTexelDeriv
= fetch_texel_deriv
;
152 * Run fragment program on the pixels in span from 'start' to 'end' - 1.
155 run_program(GLcontext
*ctx
, SWspan
*span
, GLuint start
, GLuint end
)
157 SWcontext
*swrast
= SWRAST_CONTEXT(ctx
);
158 const struct gl_fragment_program
*program
= ctx
->FragmentProgram
._Current
;
159 const GLbitfield outputsWritten
= program
->Base
.OutputsWritten
;
160 struct gl_program_machine
*machine
= &swrast
->FragProgMachine
;
163 for (i
= start
; i
< end
; i
++) {
164 if (span
->array
->mask
[i
]) {
165 init_machine(ctx
, machine
, program
, span
, i
);
167 if (_mesa_execute_program(ctx
, &program
->Base
, machine
)) {
169 /* Store result color */
170 if (outputsWritten
& (1 << FRAG_RESULT_COLR
)) {
171 COPY_4V(span
->array
->attribs
[FRAG_ATTRIB_COL0
][i
],
172 machine
->Outputs
[FRAG_RESULT_COLR
]);
175 /* Multiple drawbuffers / render targets
176 * Note that colors beyond 0 and 1 will overwrite other
177 * attributes, such as FOGC, TEX0, TEX1, etc. That's OK.
180 for (buf
= 0; buf
< ctx
->DrawBuffer
->_NumColorDrawBuffers
; buf
++) {
181 if (outputsWritten
& (1 << (FRAG_RESULT_DATA0
+ buf
))) {
182 COPY_4V(span
->array
->attribs
[FRAG_ATTRIB_COL0
+ buf
][i
],
183 machine
->Outputs
[FRAG_RESULT_DATA0
+ buf
]);
188 /* Store result depth/z */
189 if (outputsWritten
& (1 << FRAG_RESULT_DEPR
)) {
190 const GLfloat depth
= machine
->Outputs
[FRAG_RESULT_DEPR
][2];
192 span
->array
->z
[i
] = 0;
193 else if (depth
>= 1.0)
194 span
->array
->z
[i
] = ctx
->DrawBuffer
->_DepthMax
;
196 span
->array
->z
[i
] = IROUND(depth
* ctx
->DrawBuffer
->_DepthMaxF
);
200 /* killed fragment */
201 span
->array
->mask
[i
] = GL_FALSE
;
202 span
->writeAll
= GL_FALSE
;
210 * Execute the current fragment program for all the fragments
214 _swrast_exec_fragment_program( GLcontext
*ctx
, SWspan
*span
)
216 const struct gl_fragment_program
*program
= ctx
->FragmentProgram
._Current
;
218 /* incoming colors should be floats */
219 if (program
->Base
.InputsRead
& FRAG_BIT_COL0
) {
220 ASSERT(span
->array
->ChanType
== GL_FLOAT
);
223 ctx
->_CurrentProgram
= GL_FRAGMENT_PROGRAM_ARB
; /* or NV, doesn't matter */
225 run_program(ctx
, span
, 0, span
->end
);
227 if (program
->Base
.OutputsWritten
& (1 << FRAG_RESULT_COLR
)) {
228 span
->interpMask
&= ~SPAN_RGBA
;
229 span
->arrayMask
|= SPAN_RGBA
;
232 if (program
->Base
.OutputsWritten
& (1 << FRAG_RESULT_DEPR
)) {
233 span
->interpMask
&= ~SPAN_Z
;
234 span
->arrayMask
|= SPAN_Z
;
237 ctx
->_CurrentProgram
= 0;