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_draw.h"
49#include "st_format.h"
50#include "st_nir.h"
51#include "st_program.h"
52#include "st_util.h"
53
54#include "pipe/p_context.h"
55#include "pipe/p_shader_tokens.h"
56#include "pipe/p_state.h"
57#include "pipe/p_defines.h"
58#include "util/format/u_format.h"
59#include "util/u_inlines.h"
60#include "util/u_simple_shaders.h"
61
62#include "cso_cache/cso_context.h"
63
64
65/**
66 * Do per-context initialization for glClear.
67 */
68void
69st_init_clear(struct st_context *st)
70{
71   memset(&st->clear, 0, sizeof(st->clear));
72
73   st->clear.raster.half_pixel_center = 1;
74   st->clear.raster.bottom_edge_rule = 1;
75   st->clear.raster.depth_clip_near = 1;
76   st->clear.raster.depth_clip_far = 1;
77}
78
79
80/**
81 * Free per-context state for glClear.
82 */
83void
84st_destroy_clear(struct st_context *st)
85{
86   if (st->clear.fs) {
87      st->pipe->delete_fs_state(st->pipe, st->clear.fs);
88      st->clear.fs = NULL;
89   }
90   if (st->clear.vs) {
91      st->pipe->delete_vs_state(st->pipe, st->clear.vs);
92      st->clear.vs = NULL;
93   }
94   if (st->clear.vs_layered) {
95      st->pipe->delete_vs_state(st->pipe, st->clear.vs_layered);
96      st->clear.vs_layered = NULL;
97   }
98   if (st->clear.gs_layered) {
99      st->pipe->delete_gs_state(st->pipe, st->clear.gs_layered);
100      st->clear.gs_layered = NULL;
101   }
102}
103
104
105/**
106 * Helper function to set the clear color fragment shader.
107 */
108static void
109set_clearcolor_fs(struct st_context *st, union pipe_color_union *color)
110{
111   struct pipe_screen *pscreen = st->screen;
112   bool use_nir = PIPE_SHADER_IR_NIR ==
113      pscreen->get_shader_param(pscreen, PIPE_SHADER_VERTEX,
114                                PIPE_SHADER_CAP_PREFERRED_IR);
115   struct pipe_constant_buffer cb = {
116      .user_buffer = color->f,
117      .buffer_size = 4 * sizeof(float),
118   };
119   st->pipe->set_constant_buffer(st->pipe, PIPE_SHADER_FRAGMENT, 0,
120                                false, &cb);
121
122   if (!st->clear.fs) {
123      if (use_nir) {
124         st->clear.fs = st_nir_make_clearcolor_shader(st);
125      } else {
126         st->clear.fs = util_make_fs_clear_all_cbufs(st->pipe);
127      }
128   }
129
130   cso_set_fragment_shader_handle(st->cso_context, st->clear.fs);
131}
132
133static void *
134make_nir_clear_vertex_shader(struct st_context *st, bool layered)
135{
136   const char *shader_name = layered ? "layered clear VS" : "clear VS";
137   unsigned inputs[] = {
138      VERT_ATTRIB_POS,
139      SYSTEM_VALUE_INSTANCE_ID,
140   };
141   unsigned outputs[] = {
142      VARYING_SLOT_POS,
143      VARYING_SLOT_LAYER
144   };
145
146   return st_nir_make_passthrough_shader(st, shader_name, MESA_SHADER_VERTEX,
147                                         layered ? 2 : 1, inputs, outputs,
148                                         NULL, (1 << 1));
149}
150
151
152/**
153 * Helper function to set the vertex shader.
154 */
155static inline void
156set_vertex_shader(struct st_context *st)
157{
158   struct pipe_screen *pscreen = st->screen;
159   bool use_nir = PIPE_SHADER_IR_NIR ==
160      pscreen->get_shader_param(pscreen, PIPE_SHADER_VERTEX,
161                                PIPE_SHADER_CAP_PREFERRED_IR);
162
163   /* vertex shader - still required to provide the linkage between
164    * fragment shader input semantics and vertex_element/buffers.
165    */
166   if (!st->clear.vs)
167   {
168      if (use_nir) {
169         st->clear.vs = make_nir_clear_vertex_shader(st, false);
170      } else {
171         const enum tgsi_semantic semantic_names[] = {
172            TGSI_SEMANTIC_POSITION,
173         };
174         const uint semantic_indexes[] = { 0 };
175         st->clear.vs = util_make_vertex_passthrough_shader(st->pipe, 1,
176                                                            semantic_names,
177                                                            semantic_indexes,
178                                                            FALSE);
179      }
180   }
181
182   cso_set_vertex_shader_handle(st->cso_context, st->clear.vs);
183   cso_set_geometry_shader_handle(st->cso_context, NULL);
184}
185
186
187static void
188set_vertex_shader_layered(struct st_context *st)
189{
190   struct pipe_context *pipe = st->pipe;
191   struct pipe_screen *pscreen = st->screen;
192   bool use_nir = PIPE_SHADER_IR_NIR ==
193      pscreen->get_shader_param(pscreen, PIPE_SHADER_VERTEX,
194                                PIPE_SHADER_CAP_PREFERRED_IR);
195
196   if (!st->screen->get_param(st->screen, PIPE_CAP_VS_INSTANCEID)) {
197      assert(!"Got layered clear, but VS instancing is unsupported");
198      set_vertex_shader(st);
199      return;
200   }
201
202   if (!st->clear.vs_layered) {
203      bool vs_layer =
204         st->screen->get_param(st->screen, PIPE_CAP_VS_LAYER_VIEWPORT);
205      if (vs_layer) {
206         st->clear.vs_layered =
207            use_nir ? make_nir_clear_vertex_shader(st, true)
208                    : util_make_layered_clear_vertex_shader(pipe);
209      } else {
210         st->clear.vs_layered = util_make_layered_clear_helper_vertex_shader(pipe);
211         st->clear.gs_layered = util_make_layered_clear_geometry_shader(pipe);
212      }
213   }
214
215   cso_set_vertex_shader_handle(st->cso_context, st->clear.vs_layered);
216   cso_set_geometry_shader_handle(st->cso_context, st->clear.gs_layered);
217}
218
219
220/**
221 * Do glClear by drawing a quadrilateral.
222 * The vertices of the quad will be computed from the
223 * ctx->DrawBuffer->_X/Ymin/max fields.
224 */
225static void
226clear_with_quad(struct gl_context *ctx, unsigned clear_buffers)
227{
228   struct st_context *st = st_context(ctx);
229   struct cso_context *cso = st->cso_context;
230   const struct gl_framebuffer *fb = ctx->DrawBuffer;
231   const GLfloat fb_width = (GLfloat) fb->Width;
232   const GLfloat fb_height = (GLfloat) fb->Height;
233
234   _mesa_update_draw_buffer_bounds(ctx, ctx->DrawBuffer);
235
236   const GLfloat x0 = (GLfloat) ctx->DrawBuffer->_Xmin / fb_width * 2.0f - 1.0f;
237   const GLfloat x1 = (GLfloat) ctx->DrawBuffer->_Xmax / fb_width * 2.0f - 1.0f;
238   const GLfloat y0 = (GLfloat) ctx->DrawBuffer->_Ymin / fb_height * 2.0f - 1.0f;
239   const GLfloat y1 = (GLfloat) ctx->DrawBuffer->_Ymax / fb_height * 2.0f - 1.0f;
240   unsigned num_layers = st->state.fb_num_layers;
241
242   /*
243   printf("%s %s%s%s %f,%f %f,%f\n", __func__,
244	  color ? "color, " : "",
245	  depth ? "depth, " : "",
246	  stencil ? "stencil" : "",
247	  x0, y0,
248	  x1, y1);
249   */
250
251   cso_save_state(cso, (CSO_BIT_BLEND |
252                        CSO_BIT_STENCIL_REF |
253                        CSO_BIT_DEPTH_STENCIL_ALPHA |
254                        CSO_BIT_RASTERIZER |
255                        CSO_BIT_SAMPLE_MASK |
256                        CSO_BIT_MIN_SAMPLES |
257                        CSO_BIT_VIEWPORT |
258                        CSO_BIT_STREAM_OUTPUTS |
259                        CSO_BIT_VERTEX_ELEMENTS |
260                        (st->active_queries ? CSO_BIT_PAUSE_QUERIES : 0) |
261                        CSO_BITS_ALL_SHADERS));
262
263   /* blend state: RGBA masking */
264   {
265      struct pipe_blend_state blend;
266      memset(&blend, 0, sizeof(blend));
267      if (clear_buffers & PIPE_CLEAR_COLOR) {
268         int num_buffers = ctx->Extensions.EXT_draw_buffers2 ?
269                           ctx->DrawBuffer->_NumColorDrawBuffers : 1;
270         int i;
271
272         blend.independent_blend_enable = num_buffers > 1;
273         blend.max_rt = num_buffers - 1;
274
275         for (i = 0; i < num_buffers; i++) {
276            if (!(clear_buffers & (PIPE_CLEAR_COLOR0 << i)))
277               continue;
278
279            blend.rt[i].colormask = GET_COLORMASK(ctx->Color.ColorMask, i);
280         }
281
282         if (ctx->Color.DitherFlag)
283            blend.dither = 1;
284      }
285      cso_set_blend(cso, &blend);
286   }
287
288   /* depth_stencil state: always pass/set to ref value */
289   {
290      struct pipe_depth_stencil_alpha_state depth_stencil;
291      memset(&depth_stencil, 0, sizeof(depth_stencil));
292      if (clear_buffers & PIPE_CLEAR_DEPTH) {
293         depth_stencil.depth_enabled = 1;
294         depth_stencil.depth_writemask = 1;
295         depth_stencil.depth_func = PIPE_FUNC_ALWAYS;
296      }
297
298      if (clear_buffers & PIPE_CLEAR_STENCIL) {
299         struct pipe_stencil_ref stencil_ref;
300         memset(&stencil_ref, 0, sizeof(stencil_ref));
301         depth_stencil.stencil[0].enabled = 1;
302         depth_stencil.stencil[0].func = PIPE_FUNC_ALWAYS;
303         depth_stencil.stencil[0].fail_op = PIPE_STENCIL_OP_REPLACE;
304         depth_stencil.stencil[0].zpass_op = PIPE_STENCIL_OP_REPLACE;
305         depth_stencil.stencil[0].zfail_op = PIPE_STENCIL_OP_REPLACE;
306         depth_stencil.stencil[0].valuemask = 0xff;
307         depth_stencil.stencil[0].writemask = ctx->Stencil.WriteMask[0] & 0xff;
308         stencil_ref.ref_value[0] = ctx->Stencil.Clear;
309         cso_set_stencil_ref(cso, stencil_ref);
310      }
311
312      cso_set_depth_stencil_alpha(cso, &depth_stencil);
313   }
314
315   st->util_velems.count = 1;
316   cso_set_vertex_elements(cso, &st->util_velems);
317
318   cso_set_stream_outputs(cso, 0, NULL, NULL);
319   cso_set_sample_mask(cso, ~0);
320   cso_set_min_samples(cso, 1);
321   st->clear.raster.multisample = st->state.fb_num_samples > 1;
322   cso_set_rasterizer(cso, &st->clear.raster);
323
324   /* viewport state: viewport matching window dims */
325   cso_set_viewport_dims(st->cso_context, fb_width, fb_height,
326                         _mesa_fb_orientation(fb) == Y_0_TOP);
327
328   /* Set constant buffer */
329   set_clearcolor_fs(st, (union pipe_color_union*)&ctx->Color.ClearColor);
330   cso_set_tessctrl_shader_handle(cso, NULL);
331   cso_set_tesseval_shader_handle(cso, NULL);
332
333   if (num_layers > 1)
334      set_vertex_shader_layered(st);
335   else
336      set_vertex_shader(st);
337
338   /* draw quad matching scissor rect.
339    *
340    * Note: if we're only clearing depth/stencil we still setup vertices
341    * with color, but they'll be ignored.
342    *
343    * We can't translate the clear color to the colorbuffer format,
344    * because different colorbuffers may have different formats.
345    */
346   if (!st_draw_quad(st, x0, y0, x1, y1,
347                     ctx->Depth.Clear * 2.0f - 1.0f,
348                     0.0f, 0.0f, 0.0f, 0.0f,
349                     (const float *) &ctx->Color.ClearColor.f,
350                     num_layers)) {
351      _mesa_error(ctx, GL_OUT_OF_MEMORY, "glClear");
352   }
353
354   /* Restore pipe state */
355   cso_restore_state(cso, 0);
356   ctx->Array.NewVertexElements = true;
357   st->dirty |= ST_NEW_VERTEX_ARRAYS |
358                ST_NEW_FS_CONSTANTS;
359}
360
361
362/**
363 * Return if the scissor must be enabled during the clear.
364 */
365static inline GLboolean
366is_scissor_enabled(struct gl_context *ctx, struct gl_renderbuffer *rb)
367{
368   const struct gl_scissor_rect *scissor = &ctx->Scissor.ScissorArray[0];
369
370   return (ctx->Scissor.EnableFlags & 1) &&
371          (scissor->X > 0 ||
372           scissor->Y > 0 ||
373           scissor->X + scissor->Width < (int)rb->Width ||
374           scissor->Y + scissor->Height < (int)rb->Height);
375}
376
377/**
378 * Return if window rectangles must be enabled during the clear.
379 */
380static inline bool
381is_window_rectangle_enabled(struct gl_context *ctx)
382{
383   if (ctx->DrawBuffer == ctx->WinSysDrawBuffer)
384      return false;
385   return ctx->Scissor.NumWindowRects > 0 ||
386      ctx->Scissor.WindowRectMode == GL_INCLUSIVE_EXT;
387}
388
389
390/**
391 * Return if all of the stencil bits are masked.
392 */
393static inline GLboolean
394is_stencil_disabled(struct gl_context *ctx, struct gl_renderbuffer *rb)
395{
396   const GLuint stencilMax = 0xff;
397
398   assert(_mesa_get_format_bits(rb->Format, GL_STENCIL_BITS) > 0);
399   return (ctx->Stencil.WriteMask[0] & stencilMax) == 0;
400}
401
402
403/**
404 * Return if any of the stencil bits are masked.
405 */
406static inline GLboolean
407is_stencil_masked(struct gl_context *ctx, struct gl_renderbuffer *rb)
408{
409   const GLuint stencilMax = 0xff;
410
411   assert(_mesa_get_format_bits(rb->Format, GL_STENCIL_BITS) > 0);
412   return (ctx->Stencil.WriteMask[0] & stencilMax) != stencilMax;
413}
414
415void
416st_Clear(struct gl_context *ctx, GLbitfield mask)
417{
418   struct st_context *st = st_context(ctx);
419   struct gl_renderbuffer *depthRb
420      = ctx->DrawBuffer->Attachment[BUFFER_DEPTH].Renderbuffer;
421   struct gl_renderbuffer *stencilRb
422      = ctx->DrawBuffer->Attachment[BUFFER_STENCIL].Renderbuffer;
423   GLbitfield quad_buffers = 0x0;
424   GLbitfield clear_buffers = 0x0;
425   bool have_scissor_buffers = false;
426   GLuint i;
427
428   st_flush_bitmap_cache(st);
429   st_invalidate_readpix_cache(st);
430
431   /* This makes sure the pipe has the latest scissor, etc values */
432   st_validate_state(st, ST_PIPELINE_CLEAR);
433
434   if (mask & BUFFER_BITS_COLOR) {
435      for (i = 0; i < ctx->DrawBuffer->_NumColorDrawBuffers; i++) {
436         gl_buffer_index b = ctx->DrawBuffer->_ColorDrawBufferIndexes[i];
437
438         if (b != BUFFER_NONE && mask & (1 << b)) {
439            struct gl_renderbuffer *rb
440               = ctx->DrawBuffer->Attachment[b].Renderbuffer;
441            int colormask_index = ctx->Extensions.EXT_draw_buffers2 ? i : 0;
442
443            if (!rb || !rb->surface)
444               continue;
445
446            unsigned colormask =
447               GET_COLORMASK(ctx->Color.ColorMask, colormask_index);
448
449            if (!colormask)
450               continue;
451
452            unsigned surf_colormask =
453               util_format_colormask(util_format_description(rb->surface->format));
454
455            bool scissor = is_scissor_enabled(ctx, rb);
456            if ((scissor && !st->can_scissor_clear) ||
457                is_window_rectangle_enabled(ctx) ||
458                ((colormask & surf_colormask) != surf_colormask))
459               quad_buffers |= PIPE_CLEAR_COLOR0 << i;
460            else
461               clear_buffers |= PIPE_CLEAR_COLOR0 << i;
462            have_scissor_buffers |= scissor && st->can_scissor_clear;
463         }
464      }
465   }
466
467   if (mask & BUFFER_BIT_DEPTH) {
468      if (depthRb->surface && ctx->Depth.Mask) {
469         bool scissor = is_scissor_enabled(ctx, depthRb);
470         if ((scissor && !st->can_scissor_clear) ||
471             is_window_rectangle_enabled(ctx))
472            quad_buffers |= PIPE_CLEAR_DEPTH;
473         else
474            clear_buffers |= PIPE_CLEAR_DEPTH;
475         have_scissor_buffers |= scissor && st->can_scissor_clear;
476      }
477   }
478   if (mask & BUFFER_BIT_STENCIL) {
479      if (stencilRb->surface && !is_stencil_disabled(ctx, stencilRb)) {
480         bool scissor = is_scissor_enabled(ctx, stencilRb);
481         if ((scissor && !st->can_scissor_clear) ||
482             is_window_rectangle_enabled(ctx) ||
483             is_stencil_masked(ctx, stencilRb))
484            quad_buffers |= PIPE_CLEAR_STENCIL;
485         else
486            clear_buffers |= PIPE_CLEAR_STENCIL;
487         have_scissor_buffers |= scissor && st->can_scissor_clear;
488      }
489   }
490
491   /* Always clear depth and stencil together.
492    * This can only happen when the stencil writemask is not a full mask.
493    */
494   if (quad_buffers & PIPE_CLEAR_DEPTHSTENCIL &&
495       clear_buffers & PIPE_CLEAR_DEPTHSTENCIL) {
496      quad_buffers |= clear_buffers & PIPE_CLEAR_DEPTHSTENCIL;
497      clear_buffers &= ~PIPE_CLEAR_DEPTHSTENCIL;
498   }
499
500   /* Only use quad-based clearing for the renderbuffers which cannot
501    * use pipe->clear. We want to always use pipe->clear for the other
502    * renderbuffers, because it's likely to be faster.
503    */
504   if (clear_buffers) {
505      const struct gl_scissor_rect *scissor = &ctx->Scissor.ScissorArray[0];
506      struct pipe_scissor_state scissor_state = {
507         .minx = MAX2(scissor->X, 0),
508         .miny = MAX2(scissor->Y, 0),
509         .maxx = MAX2(scissor->X + scissor->Width, 0),
510         .maxy = MAX2(scissor->Y + scissor->Height, 0),
511
512      };
513
514      /* Now invert Y if needed.
515       * Gallium drivers use the convention Y=0=top for surfaces.
516       */
517      if (st->state.fb_orientation == Y_0_TOP) {
518         const struct gl_framebuffer *fb = ctx->DrawBuffer;
519         /* use intermediate variables to avoid uint underflow */
520         GLint miny, maxy;
521         miny = fb->Height - scissor_state.maxy;
522         maxy = fb->Height - scissor_state.miny;
523         scissor_state.miny = MAX2(miny, 0);
524         scissor_state.maxy = MAX2(maxy, 0);
525      }
526      if (have_scissor_buffers) {
527         const struct gl_framebuffer *fb = ctx->DrawBuffer;
528         scissor_state.maxx = MIN2(scissor_state.maxx, fb->Width);
529         scissor_state.maxy = MIN2(scissor_state.maxy, fb->Height);
530         if (scissor_state.minx >= scissor_state.maxx ||
531             scissor_state.miny >= scissor_state.maxy)
532            return;
533      }
534      /* We can't translate the clear color to the colorbuffer format,
535       * because different colorbuffers may have different formats.
536       */
537      st->pipe->clear(st->pipe, clear_buffers, have_scissor_buffers ? &scissor_state : NULL,
538                      (union pipe_color_union*)&ctx->Color.ClearColor,
539                      ctx->Depth.Clear, ctx->Stencil.Clear);
540   }
541   if (quad_buffers) {
542      clear_with_quad(ctx, quad_buffers);
543   }
544   if (mask & BUFFER_BIT_ACCUM)
545      _mesa_clear_accum_buffer(ctx);
546}
547
548