1/**************************************************************************
2 *
3 * Copyright 2007 VMware, Inc.
4 * All Rights Reserved.
5 * Copyright 2009 VMware, Inc.  All Rights Reserved.
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the
9 * "Software"), to deal in the Software without restriction, including
10 * without limitation the rights to use, copy, modify, merge, publish,
11 * distribute, sub license, and/or sell copies of the Software, and to
12 * permit persons to whom the Software is furnished to do so, subject to
13 * the following conditions:
14 *
15 * The above copyright notice and this permission notice (including the
16 * next paragraph) shall be included in all copies or substantial portions
17 * of the Software.
18 *
19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
20 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
21 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
22 * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
23 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
24 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
25 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
26 *
27 **************************************************************************/
28
29 /*
30  * Authors:
31  *   Keith Whitwell <keithw@vmware.com>
32  *   Brian Paul
33  *   Michel Dänzer
34  */
35
36#include "main/errors.h"
37#include "main/glheader.h"
38#include "main/accum.h"
39#include "main/formats.h"
40#include "main/framebuffer.h"
41#include "main/macros.h"
42#include "main/glformats.h"
43#include "program/prog_instruction.h"
44#include "st_context.h"
45#include "st_atom.h"
46#include "st_cb_bitmap.h"
47#include "st_cb_clear.h"
48#include "st_cb_fbo.h"
49#include "st_draw.h"
50#include "st_format.h"
51#include "st_nir.h"
52#include "st_program.h"
53#include "st_util.h"
54
55#include "pipe/p_context.h"
56#include "pipe/p_shader_tokens.h"
57#include "pipe/p_state.h"
58#include "pipe/p_defines.h"
59#include "util/u_format.h"
60#include "util/u_inlines.h"
61#include "util/u_simple_shaders.h"
62
63#include "cso_cache/cso_context.h"
64
65
66/**
67 * Do per-context initialization for glClear.
68 */
69void
70st_init_clear(struct st_context *st)
71{
72   memset(&st->clear, 0, sizeof(st->clear));
73
74   st->clear.raster.half_pixel_center = 1;
75   st->clear.raster.bottom_edge_rule = 1;
76   st->clear.raster.depth_clip_near = 1;
77   st->clear.raster.depth_clip_far = 1;
78}
79
80
81/**
82 * Free per-context state for glClear.
83 */
84void
85st_destroy_clear(struct st_context *st)
86{
87   if (st->clear.fs) {
88      cso_delete_fragment_shader(st->cso_context, st->clear.fs);
89      st->clear.fs = NULL;
90   }
91   if (st->clear.vs) {
92      cso_delete_vertex_shader(st->cso_context, st->clear.vs);
93      st->clear.vs = NULL;
94   }
95   if (st->clear.vs_layered) {
96      cso_delete_vertex_shader(st->cso_context, st->clear.vs_layered);
97      st->clear.vs_layered = NULL;
98   }
99   if (st->clear.gs_layered) {
100      cso_delete_geometry_shader(st->cso_context, st->clear.gs_layered);
101      st->clear.gs_layered = NULL;
102   }
103}
104
105
106/**
107 * Helper function to set the fragment shaders.
108 */
109static inline void
110set_fragment_shader(struct st_context *st)
111{
112   struct pipe_screen *pscreen = st->pipe->screen;
113   bool use_nir = PIPE_SHADER_IR_NIR ==
114      pscreen->get_shader_param(pscreen, PIPE_SHADER_VERTEX,
115                                PIPE_SHADER_CAP_PREFERRED_IR);
116
117   if (!st->clear.fs) {
118      if (use_nir) {
119         unsigned inputs[] = { VARYING_SLOT_VAR0 };
120         unsigned outputs[] = { FRAG_RESULT_COLOR };
121         unsigned interpolation[] = { INTERP_MODE_FLAT };
122         st->clear.fs = st_nir_make_passthrough_shader(st, "clear FS",
123                                                       MESA_SHADER_FRAGMENT,
124                                                       1, inputs, outputs,
125                                                       interpolation, 0);
126      } else {
127         st->clear.fs =
128            util_make_fragment_passthrough_shader(st->pipe,
129                                                  TGSI_SEMANTIC_GENERIC,
130                                                  TGSI_INTERPOLATE_CONSTANT,
131                                                  TRUE);
132      }
133   }
134
135   cso_set_fragment_shader_handle(st->cso_context, st->clear.fs);
136}
137
138
139static void *
140make_nir_clear_vertex_shader(struct st_context *st, bool layered)
141{
142   const char *shader_name = layered ? "layered clear VS" : "clear VS";
143   unsigned inputs[] = {
144      VERT_ATTRIB_POS,
145      VERT_ATTRIB_GENERIC0,
146      SYSTEM_VALUE_INSTANCE_ID,
147   };
148   unsigned outputs[] = {
149      VARYING_SLOT_POS,
150      VARYING_SLOT_VAR0,
151      VARYING_SLOT_LAYER
152   };
153
154   return st_nir_make_passthrough_shader(st, shader_name, MESA_SHADER_VERTEX,
155                                         layered ? 3 : 2, inputs, outputs,
156                                         NULL, (1 << 2));
157}
158
159
160/**
161 * Helper function to set the vertex shader.
162 */
163static inline void
164set_vertex_shader(struct st_context *st)
165{
166   struct pipe_screen *pscreen = st->pipe->screen;
167   bool use_nir = PIPE_SHADER_IR_NIR ==
168      pscreen->get_shader_param(pscreen, PIPE_SHADER_VERTEX,
169                                PIPE_SHADER_CAP_PREFERRED_IR);
170
171   /* vertex shader - still required to provide the linkage between
172    * fragment shader input semantics and vertex_element/buffers.
173    */
174   if (!st->clear.vs)
175   {
176      if (use_nir) {
177         st->clear.vs = make_nir_clear_vertex_shader(st, false);
178      } else {
179         const enum tgsi_semantic semantic_names[] = {
180            TGSI_SEMANTIC_POSITION,
181            TGSI_SEMANTIC_GENERIC
182         };
183         const uint semantic_indexes[] = { 0, 0 };
184         st->clear.vs = util_make_vertex_passthrough_shader(st->pipe, 2,
185                                                            semantic_names,
186                                                            semantic_indexes,
187                                                            FALSE);
188      }
189   }
190
191   cso_set_vertex_shader_handle(st->cso_context, st->clear.vs);
192   cso_set_geometry_shader_handle(st->cso_context, NULL);
193}
194
195
196static void
197set_vertex_shader_layered(struct st_context *st)
198{
199   struct pipe_context *pipe = st->pipe;
200   struct pipe_screen *pscreen = pipe->screen;
201   bool use_nir = PIPE_SHADER_IR_NIR ==
202      pscreen->get_shader_param(pscreen, PIPE_SHADER_VERTEX,
203                                PIPE_SHADER_CAP_PREFERRED_IR);
204
205   if (!pipe->screen->get_param(pipe->screen, PIPE_CAP_TGSI_INSTANCEID)) {
206      assert(!"Got layered clear, but VS instancing is unsupported");
207      set_vertex_shader(st);
208      return;
209   }
210
211   if (!st->clear.vs_layered) {
212      bool vs_layer =
213         pipe->screen->get_param(pipe->screen, PIPE_CAP_TGSI_VS_LAYER_VIEWPORT);
214      if (vs_layer) {
215         st->clear.vs_layered =
216            use_nir ? make_nir_clear_vertex_shader(st, true)
217                    : util_make_layered_clear_vertex_shader(pipe);
218      } else {
219         st->clear.vs_layered = util_make_layered_clear_helper_vertex_shader(pipe);
220         st->clear.gs_layered = util_make_layered_clear_geometry_shader(pipe);
221      }
222   }
223
224   cso_set_vertex_shader_handle(st->cso_context, st->clear.vs_layered);
225   cso_set_geometry_shader_handle(st->cso_context, st->clear.gs_layered);
226}
227
228
229/**
230 * Do glClear by drawing a quadrilateral.
231 * The vertices of the quad will be computed from the
232 * ctx->DrawBuffer->_X/Ymin/max fields.
233 */
234static void
235clear_with_quad(struct gl_context *ctx, unsigned clear_buffers)
236{
237   struct st_context *st = st_context(ctx);
238   struct cso_context *cso = st->cso_context;
239   const struct gl_framebuffer *fb = ctx->DrawBuffer;
240   const GLfloat fb_width = (GLfloat) fb->Width;
241   const GLfloat fb_height = (GLfloat) fb->Height;
242
243   _mesa_update_draw_buffer_bounds(ctx, ctx->DrawBuffer);
244
245   const GLfloat x0 = (GLfloat) ctx->DrawBuffer->_Xmin / fb_width * 2.0f - 1.0f;
246   const GLfloat x1 = (GLfloat) ctx->DrawBuffer->_Xmax / fb_width * 2.0f - 1.0f;
247   const GLfloat y0 = (GLfloat) ctx->DrawBuffer->_Ymin / fb_height * 2.0f - 1.0f;
248   const GLfloat y1 = (GLfloat) ctx->DrawBuffer->_Ymax / fb_height * 2.0f - 1.0f;
249   unsigned num_layers = st->state.fb_num_layers;
250
251   /*
252   printf("%s %s%s%s %f,%f %f,%f\n", __func__,
253	  color ? "color, " : "",
254	  depth ? "depth, " : "",
255	  stencil ? "stencil" : "",
256	  x0, y0,
257	  x1, y1);
258   */
259
260   cso_save_state(cso, (CSO_BIT_BLEND |
261                        CSO_BIT_STENCIL_REF |
262                        CSO_BIT_DEPTH_STENCIL_ALPHA |
263                        CSO_BIT_RASTERIZER |
264                        CSO_BIT_SAMPLE_MASK |
265                        CSO_BIT_MIN_SAMPLES |
266                        CSO_BIT_VIEWPORT |
267                        CSO_BIT_STREAM_OUTPUTS |
268                        CSO_BIT_VERTEX_ELEMENTS |
269                        CSO_BIT_AUX_VERTEX_BUFFER_SLOT |
270                        CSO_BIT_PAUSE_QUERIES |
271                        CSO_BITS_ALL_SHADERS));
272
273   /* blend state: RGBA masking */
274   {
275      struct pipe_blend_state blend;
276      memset(&blend, 0, sizeof(blend));
277      if (clear_buffers & PIPE_CLEAR_COLOR) {
278         int num_buffers = ctx->Extensions.EXT_draw_buffers2 ?
279                           ctx->DrawBuffer->_NumColorDrawBuffers : 1;
280         int i;
281
282         blend.independent_blend_enable = num_buffers > 1;
283
284         for (i = 0; i < num_buffers; i++) {
285            if (!(clear_buffers & (PIPE_CLEAR_COLOR0 << i)))
286               continue;
287
288            blend.rt[i].colormask = GET_COLORMASK(ctx->Color.ColorMask, i);
289         }
290
291         if (ctx->Color.DitherFlag)
292            blend.dither = 1;
293      }
294      cso_set_blend(cso, &blend);
295   }
296
297   /* depth_stencil state: always pass/set to ref value */
298   {
299      struct pipe_depth_stencil_alpha_state depth_stencil;
300      memset(&depth_stencil, 0, sizeof(depth_stencil));
301      if (clear_buffers & PIPE_CLEAR_DEPTH) {
302         depth_stencil.depth.enabled = 1;
303         depth_stencil.depth.writemask = 1;
304         depth_stencil.depth.func = PIPE_FUNC_ALWAYS;
305      }
306
307      if (clear_buffers & PIPE_CLEAR_STENCIL) {
308         struct pipe_stencil_ref stencil_ref;
309         memset(&stencil_ref, 0, sizeof(stencil_ref));
310         depth_stencil.stencil[0].enabled = 1;
311         depth_stencil.stencil[0].func = PIPE_FUNC_ALWAYS;
312         depth_stencil.stencil[0].fail_op = PIPE_STENCIL_OP_REPLACE;
313         depth_stencil.stencil[0].zpass_op = PIPE_STENCIL_OP_REPLACE;
314         depth_stencil.stencil[0].zfail_op = PIPE_STENCIL_OP_REPLACE;
315         depth_stencil.stencil[0].valuemask = 0xff;
316         depth_stencil.stencil[0].writemask = ctx->Stencil.WriteMask[0] & 0xff;
317         stencil_ref.ref_value[0] = ctx->Stencil.Clear;
318         cso_set_stencil_ref(cso, &stencil_ref);
319      }
320
321      cso_set_depth_stencil_alpha(cso, &depth_stencil);
322   }
323
324   cso_set_vertex_elements(cso, 2, st->util_velems);
325   cso_set_stream_outputs(cso, 0, NULL, NULL);
326   cso_set_sample_mask(cso, ~0);
327   cso_set_min_samples(cso, 1);
328   cso_set_rasterizer(cso, &st->clear.raster);
329
330   /* viewport state: viewport matching window dims */
331   cso_set_viewport_dims(st->cso_context, fb_width, fb_height,
332                         st_fb_orientation(fb) == Y_0_TOP);
333
334   set_fragment_shader(st);
335   cso_set_tessctrl_shader_handle(cso, NULL);
336   cso_set_tesseval_shader_handle(cso, NULL);
337
338   if (num_layers > 1)
339      set_vertex_shader_layered(st);
340   else
341      set_vertex_shader(st);
342
343   /* draw quad matching scissor rect.
344    *
345    * Note: if we're only clearing depth/stencil we still setup vertices
346    * with color, but they'll be ignored.
347    *
348    * We can't translate the clear color to the colorbuffer format,
349    * because different colorbuffers may have different formats.
350    */
351   if (!st_draw_quad(st, x0, y0, x1, y1,
352                     ctx->Depth.Clear * 2.0f - 1.0f,
353                     0.0f, 0.0f, 0.0f, 0.0f,
354                     (const float *) &ctx->Color.ClearColor.f,
355                     num_layers)) {
356      _mesa_error(ctx, GL_OUT_OF_MEMORY, "glClear");
357   }
358
359   /* Restore pipe state */
360   cso_restore_state(cso);
361}
362
363
364/**
365 * Return if the scissor must be enabled during the clear.
366 */
367static inline GLboolean
368is_scissor_enabled(struct gl_context *ctx, struct gl_renderbuffer *rb)
369{
370   const struct gl_scissor_rect *scissor = &ctx->Scissor.ScissorArray[0];
371
372   return (ctx->Scissor.EnableFlags & 1) &&
373          (scissor->X > 0 ||
374           scissor->Y > 0 ||
375           scissor->X + scissor->Width < (int)rb->Width ||
376           scissor->Y + scissor->Height < (int)rb->Height);
377}
378
379/**
380 * Return if window rectangles must be enabled during the clear.
381 */
382static inline bool
383is_window_rectangle_enabled(struct gl_context *ctx)
384{
385   if (ctx->DrawBuffer == ctx->WinSysDrawBuffer)
386      return false;
387   return ctx->Scissor.NumWindowRects > 0 ||
388      ctx->Scissor.WindowRectMode == GL_INCLUSIVE_EXT;
389}
390
391
392/**
393 * Return if all of the stencil bits are masked.
394 */
395static inline GLboolean
396is_stencil_disabled(struct gl_context *ctx, struct gl_renderbuffer *rb)
397{
398   const GLuint stencilMax = 0xff;
399
400   assert(_mesa_get_format_bits(rb->Format, GL_STENCIL_BITS) > 0);
401   return (ctx->Stencil.WriteMask[0] & stencilMax) == 0;
402}
403
404
405/**
406 * Return if any of the stencil bits are masked.
407 */
408static inline GLboolean
409is_stencil_masked(struct gl_context *ctx, struct gl_renderbuffer *rb)
410{
411   const GLuint stencilMax = 0xff;
412
413   assert(_mesa_get_format_bits(rb->Format, GL_STENCIL_BITS) > 0);
414   return (ctx->Stencil.WriteMask[0] & stencilMax) != stencilMax;
415}
416
417
418/**
419 * Called via ctx->Driver.Clear()
420 */
421static void
422st_Clear(struct gl_context *ctx, GLbitfield mask)
423{
424   struct st_context *st = st_context(ctx);
425   struct gl_renderbuffer *depthRb
426      = ctx->DrawBuffer->Attachment[BUFFER_DEPTH].Renderbuffer;
427   struct gl_renderbuffer *stencilRb
428      = ctx->DrawBuffer->Attachment[BUFFER_STENCIL].Renderbuffer;
429   GLbitfield quad_buffers = 0x0;
430   GLbitfield clear_buffers = 0x0;
431   GLuint i;
432
433   st_flush_bitmap_cache(st);
434   st_invalidate_readpix_cache(st);
435
436   /* This makes sure the pipe has the latest scissor, etc values */
437   st_validate_state(st, ST_PIPELINE_CLEAR);
438
439   if (mask & BUFFER_BITS_COLOR) {
440      for (i = 0; i < ctx->DrawBuffer->_NumColorDrawBuffers; i++) {
441         gl_buffer_index b = ctx->DrawBuffer->_ColorDrawBufferIndexes[i];
442
443         if (b != BUFFER_NONE && mask & (1 << b)) {
444            struct gl_renderbuffer *rb
445               = ctx->DrawBuffer->Attachment[b].Renderbuffer;
446            struct st_renderbuffer *strb = st_renderbuffer(rb);
447            int colormask_index = ctx->Extensions.EXT_draw_buffers2 ? i : 0;
448
449            if (!strb || !strb->surface)
450               continue;
451
452            unsigned colormask =
453               GET_COLORMASK(ctx->Color.ColorMask, colormask_index);
454
455            if (!colormask)
456               continue;
457
458            unsigned surf_colormask =
459               util_format_colormask(util_format_description(strb->surface->format));
460
461            if (is_scissor_enabled(ctx, rb) ||
462                is_window_rectangle_enabled(ctx) ||
463                ((colormask & surf_colormask) != surf_colormask))
464               quad_buffers |= PIPE_CLEAR_COLOR0 << i;
465            else
466               clear_buffers |= PIPE_CLEAR_COLOR0 << i;
467         }
468      }
469   }
470
471   if (mask & BUFFER_BIT_DEPTH) {
472      struct st_renderbuffer *strb = st_renderbuffer(depthRb);
473
474      if (strb->surface && ctx->Depth.Mask) {
475         if (is_scissor_enabled(ctx, depthRb) ||
476             is_window_rectangle_enabled(ctx))
477            quad_buffers |= PIPE_CLEAR_DEPTH;
478         else
479            clear_buffers |= PIPE_CLEAR_DEPTH;
480      }
481   }
482   if (mask & BUFFER_BIT_STENCIL) {
483      struct st_renderbuffer *strb = st_renderbuffer(stencilRb);
484
485      if (strb->surface && !is_stencil_disabled(ctx, stencilRb)) {
486         if (is_scissor_enabled(ctx, stencilRb) ||
487             is_window_rectangle_enabled(ctx) ||
488             is_stencil_masked(ctx, stencilRb))
489            quad_buffers |= PIPE_CLEAR_STENCIL;
490         else
491            clear_buffers |= PIPE_CLEAR_STENCIL;
492      }
493   }
494
495   /* Always clear depth and stencil together.
496    * This can only happen when the stencil writemask is not a full mask.
497    */
498   if (quad_buffers & PIPE_CLEAR_DEPTHSTENCIL &&
499       clear_buffers & PIPE_CLEAR_DEPTHSTENCIL) {
500      quad_buffers |= clear_buffers & PIPE_CLEAR_DEPTHSTENCIL;
501      clear_buffers &= ~PIPE_CLEAR_DEPTHSTENCIL;
502   }
503
504   /* Only use quad-based clearing for the renderbuffers which cannot
505    * use pipe->clear. We want to always use pipe->clear for the other
506    * renderbuffers, because it's likely to be faster.
507    */
508   if (clear_buffers) {
509      /* We can't translate the clear color to the colorbuffer format,
510       * because different colorbuffers may have different formats.
511       */
512      st->pipe->clear(st->pipe, clear_buffers,
513                      (union pipe_color_union*)&ctx->Color.ClearColor,
514                      ctx->Depth.Clear, ctx->Stencil.Clear);
515   }
516   if (quad_buffers) {
517      clear_with_quad(ctx, quad_buffers);
518   }
519   if (mask & BUFFER_BIT_ACCUM)
520      _mesa_clear_accum_buffer(ctx);
521}
522
523
524void
525st_init_clear_functions(struct dd_function_table *functions)
526{
527   functions->Clear = st_Clear;
528}
529