src/gallium/auxiliary/util/u_framebuffer.c

   1 /**************************************************************************
   2  *
   3  * Copyright 2009-2010 VMware, Inc.  All Rights Reserved.
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a
   6  * copy of this software and associated documentation files (the
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  10  * permit persons to whom the Software is furnished to do so, subject to
  11  * the following conditions:
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  13  * The above copyright notice and this permission notice (including the
  14  * next paragraph) shall be included in all copies or substantial portions
  15  * of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  18  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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  26
  27 /**
  28  * @file
  29  * Framebuffer utility functions.
  30  *
  31  * @author Brian Paul
  32  */
  33
  34
  35 #include "pipe/p_screen.h"
  36 #include "pipe/p_state.h"
  37 #include "pipe/p_defines.h"
  38 #include "util/u_inlines.h"
  39
  40 #include "util/u_memory.h"
  41 #include "util/u_framebuffer.h"
  42
  43
  44 /**
  45  * Compare pipe_framebuffer_state objects.
  46  * \return TRUE if same, FALSE if different
  47  */
  48 boolean
  49 util_framebuffer_state_equal(const struct pipe_framebuffer_state *dst,
  50                              const struct pipe_framebuffer_state *src)
  51 {
  52    unsigned i;
  53
  54    if (dst->width != src->width ||
  55        dst->height != src->height)
  56       return FALSE;
  57
  58    if (dst->samples != src->samples ||
  59        dst->layers  != src->layers)
  60       return FALSE;
  61
  62    if (dst->nr_cbufs != src->nr_cbufs) {
  63       return FALSE;
  64    }
  65
  66    for (i = 0; i < src->nr_cbufs; i++) {
  67       if (dst->cbufs[i] != src->cbufs[i]) {
  68          return FALSE;
  69       }
  70    }
  71
  72    if (dst->zsbuf != src->zsbuf) {
  73       return FALSE;
  74    }
  75
  76    return TRUE;
  77 }
  78
  79
  80 /**
  81  * Copy framebuffer state from src to dst, updating refcounts.
  82  */
  83 void
  84 util_copy_framebuffer_state(struct pipe_framebuffer_state *dst,
  85                             const struct pipe_framebuffer_state *src)
  86 {
  87    unsigned i;
  88
  89    if (src) {
  90       dst->width = src->width;
  91       dst->height = src->height;
  92
  93       dst->samples = src->samples;
  94       dst->layers  = src->layers;
  95
  96       for (i = 0; i < src->nr_cbufs; i++)
  97          pipe_surface_reference(&dst->cbufs[i], src->cbufs[i]);
  98
  99       /* Set remaining dest cbuf pointers to NULL */
 100       for ( ; i < ARRAY_SIZE(dst->cbufs); i++)
 101          pipe_surface_reference(&dst->cbufs[i], NULL);
 102
 103       dst->nr_cbufs = src->nr_cbufs;
 104
 105       pipe_surface_reference(&dst->zsbuf, src->zsbuf);
 106    } else {
 107       dst->width = 0;
 108       dst->height = 0;
 109
 110       dst->samples = 0;
 111       dst->layers  = 0;
 112
 113       for (i = 0 ; i < ARRAY_SIZE(dst->cbufs); i++)
 114          pipe_surface_reference(&dst->cbufs[i], NULL);
 115
 116       dst->nr_cbufs = 0;
 117
 118       pipe_surface_reference(&dst->zsbuf, NULL);
 119    }
 120 }
 121
 122
 123 void
 124 util_unreference_framebuffer_state(struct pipe_framebuffer_state *fb)
 125 {
 126    unsigned i;
 127
 128    for (i = 0; i < fb->nr_cbufs; i++) {
 129       pipe_surface_reference(&fb->cbufs[i], NULL);
 130    }
 131
 132    pipe_surface_reference(&fb->zsbuf, NULL);
 133
 134    fb->samples = fb->layers = 0;
 135    fb->width = fb->height = 0;
 136    fb->nr_cbufs = 0;
 137 }
 138
 139
 140 /* Where multiple sizes are allowed for framebuffer surfaces, find the
 141  * minimum width and height of all bound surfaces.
 142  */
 143 boolean
 144 util_framebuffer_min_size(const struct pipe_framebuffer_state *fb,
 145                           unsigned *width,
 146                           unsigned *height)
 147 {
 148    unsigned w = ~0;
 149    unsigned h = ~0;
 150    unsigned i;
 151
 152    for (i = 0; i < fb->nr_cbufs; i++) {
 153       if (!fb->cbufs[i])
 154          continue;
 155
 156       w = MIN2(w, fb->cbufs[i]->width);
 157       h = MIN2(h, fb->cbufs[i]->height);
 158    }
 159
 160    if (fb->zsbuf) {
 161       w = MIN2(w, fb->zsbuf->width);
 162       h = MIN2(h, fb->zsbuf->height);
 163    }
 164
 165    if (w == ~0u) {
 166       *width = 0;
 167       *height = 0;
 168       return FALSE;
 169    }
 170    else {
 171       *width = w;
 172       *height = h;
 173       return TRUE;
 174    }
 175 }
 176
 177
 178 /**
 179  * Return the number of layers set in the framebuffer state.
 180  */
 181 unsigned
 182 util_framebuffer_get_num_layers(const struct pipe_framebuffer_state *fb)
 183 {
 184         unsigned i, num_layers = 0;
 185
 186         /**
 187          * In the case of ARB_framebuffer_no_attachment
 188          * we obtain the number of layers directly from
 189          * the framebuffer state.
 190          */
 191         if (!(fb->nr_cbufs || fb->zsbuf))
 192                 return fb->layers;
 193
 194         for (i = 0; i < fb->nr_cbufs; i++) {
 195                 if (fb->cbufs[i]) {
 196                         unsigned num = fb->cbufs[i]->u.tex.last_layer -
 197                                        fb->cbufs[i]->u.tex.first_layer + 1;
 198                         num_layers = MAX2(num_layers, num);
 199                 }
 200         }
 201         if (fb->zsbuf) {
 202                 unsigned num = fb->zsbuf->u.tex.last_layer -
 203                                fb->zsbuf->u.tex.first_layer + 1;
 204                 num_layers = MAX2(num_layers, num);
 205         }
 206         return num_layers;
 207 }
 208
 209
 210 /**
 211  * Return the number of MSAA samples.
 212  */
 213 unsigned
 214 util_framebuffer_get_num_samples(const struct pipe_framebuffer_state *fb)
 215 {
 216    unsigned i;
 217
 218    /**
 219     * In the case of ARB_framebuffer_no_attachment
 220     * we obtain the number of samples directly from
 221     * the framebuffer state.
 222     *
 223     * NOTE: fb->samples may wind up as zero due to memset()'s on internal
 224     *       driver structures on their initialization and so we take the
 225     *       MAX here to ensure we have a valid number of samples. However,
 226     *       if samples is legitimately not getting set somewhere
 227     *       multi-sampling will evidently break.
 228     */
 229    if (!(fb->nr_cbufs || fb->zsbuf))
 230       return MAX2(fb->samples, 1);
 231
 232    /**
 233     * If a driver doesn't advertise PIPE_CAP_SURFACE_SAMPLE_COUNT,
 234     * pipe_surface::nr_samples will always be 0.
 235     */
 236    for (i = 0; i < fb->nr_cbufs; i++) {
 237       if (fb->cbufs[i]) {
 238          return MAX3(1, fb->cbufs[i]->texture->nr_samples,
 239                      fb->cbufs[i]->nr_samples);
 240       }
 241    }
 242    if (fb->zsbuf) {
 243       return MAX3(1, fb->zsbuf->texture->nr_samples,
 244                   fb->zsbuf->nr_samples);
 245    }
 246
 247    return 1;
 248 }
 249
 250
 251 /**
 252  * Flip the sample location state along the Y axis.
 253  */
 254 void
 255 util_sample_locations_flip_y(struct pipe_screen *screen, unsigned fb_height,
 256                              unsigned samples, uint8_t *locations)
 257 {
 258    unsigned row, i, shift, grid_width, grid_height;
 259    uint8_t new_locations[
 260       PIPE_MAX_SAMPLE_LOCATION_GRID_SIZE *
 261       PIPE_MAX_SAMPLE_LOCATION_GRID_SIZE * 32];
 262
 263    screen->get_sample_pixel_grid(screen, samples, &grid_width, &grid_height);
 264
 265    shift = fb_height % grid_height;
 266
 267    for (row = 0; row < grid_height; row++) {
 268       unsigned row_size = grid_width * samples;
 269       for (i = 0; i < row_size; i++) {
 270          unsigned dest_row = grid_height - row - 1;
 271          /* this relies on unsigned integer wraparound behaviour */
 272          dest_row = (dest_row - shift) % grid_height;
 273          new_locations[dest_row * row_size + i] = locations[row * row_size + i];
 274       }
 275    }
 276
 277    memcpy(locations, new_locations, grid_width * grid_height * samples);
 278 }