src/mesa/drivers/dri/intel/intel_buffers.c

   1 /**************************************************************************
   2  *
   3  * Copyright 2003 Tungsten Graphics, Inc., Cedar Park, Texas.
   4  * All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * 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, sub license, 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:
  13  *
  14  * The above copyright notice and this permission notice (including the
  15  * next paragraph) shall be included in all copies or substantial portions
  16  * of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  19  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
  21  * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
  22  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  23  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  24  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  **************************************************************************/
  27
  28 #include "intel_context.h"
  29 #include "intel_buffers.h"
  30 #include "intel_fbo.h"
  31 #include "main/framebuffer.h"
  32
  33 /**
  34  * Return pointer to current color drawing region, or NULL.
  35  */
  36 struct intel_region *
  37 intel_drawbuf_region(struct intel_context *intel)
  38 {
  39    struct intel_renderbuffer *irbColor =
  40       intel_renderbuffer(intel->ctx.DrawBuffer->_ColorDrawBuffers[0]);
  41    if (irbColor)
  42       return irbColor->region;
  43    else
  44       return NULL;
  45 }
  46
  47 /**
  48  * Return pointer to current color reading region, or NULL.
  49  */
  50 struct intel_region *
  51 intel_readbuf_region(struct intel_context *intel)
  52 {
  53    struct intel_renderbuffer *irb
  54       = intel_renderbuffer(intel->ctx.ReadBuffer->_ColorReadBuffer);
  55    if (irb)
  56       return irb->region;
  57    else
  58       return NULL;
  59 }
  60
  61 /**
  62  * Check if we're about to draw into the front color buffer.
  63  * If so, set the intel->front_buffer_dirty field to true.
  64  */
  65 void
  66 intel_check_front_buffer_rendering(struct intel_context *intel)
  67 {
  68    const struct gl_framebuffer *fb = intel->ctx.DrawBuffer;
  69    if (fb->Name == 0) {
  70       /* drawing to window system buffer */
  71       if (fb->_NumColorDrawBuffers > 0) {
  72          if (fb->_ColorDrawBufferIndexes[0] == BUFFER_FRONT_LEFT) {
  73             intel->front_buffer_dirty = GL_TRUE;
  74          }
  75       }
  76    }
  77 }
  78
  79
  80 /**
  81  * Update the hardware state for drawing into a window or framebuffer object.
  82  *
  83  * Called by glDrawBuffer, glBindFramebufferEXT, MakeCurrent, and other
  84  * places within the driver.
  85  *
  86  * Basically, this needs to be called any time the current framebuffer
  87  * changes, the renderbuffers change, or we need to draw into different
  88  * color buffers.
  89  */
  90 void
  91 intel_draw_buffer(struct gl_context * ctx, struct gl_framebuffer *fb)
  92 {
  93    struct intel_context *intel = intel_context(ctx);
  94    struct intel_region *colorRegions[MAX_DRAW_BUFFERS], *depthRegion = NULL;
  95    struct intel_renderbuffer *irbDepth = NULL, *irbStencil = NULL;
  96    bool fb_has_hiz = intel_framebuffer_has_hiz(fb);
  97
  98    if (!fb) {
  99       /* this can happen during the initial context initialization */
 100       return;
 101    }
 102
 103    /* Do this here, not core Mesa, since this function is called from
 104     * many places within the driver.
 105     */
 106    if (ctx->NewState & _NEW_BUFFERS) {
 107       /* this updates the DrawBuffer->_NumColorDrawBuffers fields, etc */
 108       _mesa_update_framebuffer(ctx);
 109       /* this updates the DrawBuffer's Width/Height if it's a FBO */
 110       _mesa_update_draw_buffer_bounds(ctx);
 111    }
 112
 113    if (fb->_Status != GL_FRAMEBUFFER_COMPLETE_EXT) {
 114       /* this may occur when we're called by glBindFrameBuffer() during
 115        * the process of someone setting up renderbuffers, etc.
 116        */
 117       /*_mesa_debug(ctx, "DrawBuffer: incomplete user FBO\n");*/
 118       return;
 119    }
 120
 121    /* How many color buffers are we drawing into?
 122     *
 123     * If there are zero buffers or the buffer is too big, don't configure any
 124     * regions for hardware drawing.  We'll fallback to software below.  Not
 125     * having regions set makes some of the software fallback paths faster.
 126     */
 127    if ((fb->Width > ctx->Const.MaxRenderbufferSize)
 128        || (fb->Height > ctx->Const.MaxRenderbufferSize)
 129        || (fb->_NumColorDrawBuffers == 0)) {
 130       /* writing to 0  */
 131       colorRegions[0] = NULL;
 132    }
 133    else if (fb->_NumColorDrawBuffers > 1) {
 134        int i;
 135        struct intel_renderbuffer *irb;
 136
 137        for (i = 0; i < fb->_NumColorDrawBuffers; i++) {
 138            irb = intel_renderbuffer(fb->_ColorDrawBuffers[i]);
 139            colorRegions[i] = irb ? irb->region : NULL;
 140        }
 141    }
 142    else {
 143       /* Get the intel_renderbuffer for the single colorbuffer we're drawing
 144        * into.
 145        */
 146       if (fb->Name == 0) {
 147          /* drawing to window system buffer */
 148          if (fb->_ColorDrawBufferIndexes[0] == BUFFER_FRONT_LEFT)
 149             colorRegions[0] = intel_get_rb_region(fb, BUFFER_FRONT_LEFT);
 150          else
 151             colorRegions[0] = intel_get_rb_region(fb, BUFFER_BACK_LEFT);
 152       }
 153       else {
 154          /* drawing to user-created FBO */
 155          struct intel_renderbuffer *irb;
 156          irb = intel_renderbuffer(fb->_ColorDrawBuffers[0]);
 157          colorRegions[0] = (irb && irb->region) ? irb->region : NULL;
 158       }
 159    }
 160
 161    if (!colorRegions[0]) {
 162       FALLBACK(intel, INTEL_FALLBACK_DRAW_BUFFER, GL_TRUE);
 163    }
 164    else {
 165       FALLBACK(intel, INTEL_FALLBACK_DRAW_BUFFER, GL_FALSE);
 166    }
 167
 168    /***
 169     *** Get depth buffer region and check if we need a software fallback.
 170     ***/
 171    if (fb->_DepthBuffer && fb->_DepthBuffer->Wrapped) {
 172       irbDepth = intel_renderbuffer(fb->_DepthBuffer->Wrapped);
 173       if (irbDepth && irbDepth->region) {
 174          assert(!fb_has_hiz || irbDepth->Base.Format != MESA_FORMAT_S8_Z24);
 175          FALLBACK(intel, INTEL_FALLBACK_DEPTH_BUFFER, GL_FALSE);
 176          depthRegion = irbDepth->region;
 177       }
 178       else {
 179          FALLBACK(intel, INTEL_FALLBACK_DEPTH_BUFFER, GL_TRUE);
 180          depthRegion = NULL;
 181       }
 182    }
 183    else {
 184       /* not using depth buffer */
 185       FALLBACK(intel, INTEL_FALLBACK_DEPTH_BUFFER, GL_FALSE);
 186       depthRegion = NULL;
 187    }
 188
 189    /***
 190     *** Stencil buffer
 191     ***/
 192    if (fb->_StencilBuffer && fb->_StencilBuffer->Wrapped) {
 193       irbStencil = intel_renderbuffer(fb->_StencilBuffer->Wrapped);
 194       if (irbStencil && irbStencil->region) {
 195          if (!intel->has_separate_stencil)
 196             assert(irbStencil->Base.Format == MESA_FORMAT_S8_Z24);
 197          if (fb_has_hiz || intel->must_use_separate_stencil)
 198             assert(irbStencil->Base.Format == MESA_FORMAT_S8);
 199          if (irbStencil->Base.Format == MESA_FORMAT_S8)
 200             assert(intel->has_separate_stencil);
 201          FALLBACK(intel, INTEL_FALLBACK_STENCIL_BUFFER, GL_FALSE);
 202       }
 203       else {
 204          FALLBACK(intel, INTEL_FALLBACK_STENCIL_BUFFER, GL_TRUE);
 205       }
 206    }
 207    else {
 208       /* XXX FBO: instead of FALSE, pass ctx->Stencil._Enabled ??? */
 209       FALLBACK(intel, INTEL_FALLBACK_STENCIL_BUFFER, GL_FALSE);
 210    }
 211
 212    /* If we have a (packed) stencil buffer attached but no depth buffer,
 213     * we still need to set up the shared depth/stencil state so we can use it.
 214     */
 215    if (depthRegion == NULL && irbStencil && irbStencil->region
 216        && irbStencil->Base.Format == MESA_FORMAT_S8_Z24) {
 217       depthRegion = irbStencil->region;
 218    }
 219
 220    /*
 221     * Update depth and stencil test state
 222     */
 223    if (ctx->Driver.Enable) {
 224       ctx->Driver.Enable(ctx, GL_DEPTH_TEST,
 225                          (ctx->Depth.Test && fb->Visual.depthBits > 0));
 226       ctx->Driver.Enable(ctx, GL_STENCIL_TEST,
 227                          (ctx->Stencil.Enabled && fb->Visual.stencilBits > 0));
 228    }
 229    else {
 230       /* Mesa's Stencil._Enabled field is updated when
 231        * _NEW_BUFFERS | _NEW_STENCIL, but i965 code assumes that the value
 232        * only changes with _NEW_STENCIL (which seems sensible).  So flag it
 233        * here since this is the _NEW_BUFFERS path.
 234        */
 235       intel->NewGLState |= (_NEW_DEPTH | _NEW_STENCIL);
 236    }
 237
 238    intel->vtbl.set_draw_region(intel, colorRegions, depthRegion,
 239                                fb->_NumColorDrawBuffers);
 240    intel->NewGLState |= _NEW_BUFFERS;
 241
 242    /* update viewport since it depends on window size */
 243 #ifdef I915
 244    intelCalcViewport(ctx);
 245 #else
 246    intel->NewGLState |= _NEW_VIEWPORT;
 247 #endif
 248    /* Set state we know depends on drawable parameters:
 249     */
 250    if (ctx->Driver.Scissor)
 251       ctx->Driver.Scissor(ctx, ctx->Scissor.X, ctx->Scissor.Y,
 252                           ctx->Scissor.Width, ctx->Scissor.Height);
 253    intel->NewGLState |= _NEW_SCISSOR;
 254
 255    if (ctx->Driver.DepthRange)
 256       ctx->Driver.DepthRange(ctx,
 257                              ctx->Viewport.Near,
 258                              ctx->Viewport.Far);
 259
 260    /* Update culling direction which changes depending on the
 261     * orientation of the buffer:
 262     */
 263    if (ctx->Driver.FrontFace)
 264       ctx->Driver.FrontFace(ctx, ctx->Polygon.FrontFace);
 265    else
 266       intel->NewGLState |= _NEW_POLYGON;
 267 }
 268
 269
 270 static void
 271 intelDrawBuffer(struct gl_context * ctx, GLenum mode)
 272 {
 273    if ((ctx->DrawBuffer != NULL) && (ctx->DrawBuffer->Name == 0)) {
 274       struct intel_context *const intel = intel_context(ctx);
 275       const GLboolean was_front_buffer_rendering =
 276         intel->is_front_buffer_rendering;
 277
 278       intel->is_front_buffer_rendering = (mode == GL_FRONT_LEFT)
 279         || (mode == GL_FRONT);
 280
 281       /* If we weren't front-buffer rendering before but we are now,
 282        * invalidate our DRI drawable so we'll ask for new buffers
 283        * (including the fake front) before we start rendering again.
 284        */
 285       if (!was_front_buffer_rendering && intel->is_front_buffer_rendering)
 286          dri2InvalidateDrawable(intel->driContext->driDrawablePriv);
 287    }
 288
 289    intel_draw_buffer(ctx, ctx->DrawBuffer);
 290 }
 291
 292
 293 static void
 294 intelReadBuffer(struct gl_context * ctx, GLenum mode)
 295 {
 296    if ((ctx->DrawBuffer != NULL) && (ctx->DrawBuffer->Name == 0)) {
 297       struct intel_context *const intel = intel_context(ctx);
 298       const GLboolean was_front_buffer_reading =
 299         intel->is_front_buffer_reading;
 300
 301       intel->is_front_buffer_reading = (mode == GL_FRONT_LEFT)
 302         || (mode == GL_FRONT);
 303
 304       /* If we weren't front-buffer reading before but we are now,
 305        * invalidate our DRI drawable so we'll ask for new buffers
 306        * (including the fake front) before we start reading again.
 307        */
 308       if (!was_front_buffer_reading && intel->is_front_buffer_reading)
 309          dri2InvalidateDrawable(intel->driContext->driReadablePriv);
 310    }
 311 }
 312
 313
 314 void
 315 intelInitBufferFuncs(struct dd_function_table *functions)
 316 {
 317    functions->DrawBuffer = intelDrawBuffer;
 318    functions->ReadBuffer = intelReadBuffer;
 319 }