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 "intel_batchbuffer.h"
  32 #include "main/framebuffer.h"
  33
  34
  35 /**
  36  * XXX move this into a new dri/common/cliprects.c file.
  37  */
  38 GLboolean
  39 intel_intersect_cliprects(drm_clip_rect_t * dst,
  40                           const drm_clip_rect_t * a,
  41                           const drm_clip_rect_t * b)
  42 {
  43    GLint bx = b->x1;
  44    GLint by = b->y1;
  45    GLint bw = b->x2 - bx;
  46    GLint bh = b->y2 - by;
  47
  48    if (bx < a->x1)
  49       bw -= a->x1 - bx, bx = a->x1;
  50    if (by < a->y1)
  51       bh -= a->y1 - by, by = a->y1;
  52    if (bx + bw > a->x2)
  53       bw = a->x2 - bx;
  54    if (by + bh > a->y2)
  55       bh = a->y2 - by;
  56    if (bw <= 0)
  57       return GL_FALSE;
  58    if (bh <= 0)
  59       return GL_FALSE;
  60
  61    dst->x1 = bx;
  62    dst->y1 = by;
  63    dst->x2 = bx + bw;
  64    dst->y2 = by + bh;
  65
  66    return GL_TRUE;
  67 }
  68
  69 /**
  70  * Return pointer to current color drawing region, or NULL.
  71  */
  72 struct intel_region *
  73 intel_drawbuf_region(struct intel_context *intel)
  74 {
  75    struct intel_renderbuffer *irbColor =
  76       intel_renderbuffer(intel->ctx.DrawBuffer->_ColorDrawBuffers[0]);
  77    if (irbColor)
  78       return irbColor->region;
  79    else
  80       return NULL;
  81 }
  82
  83 /**
  84  * Return pointer to current color reading region, or NULL.
  85  */
  86 struct intel_region *
  87 intel_readbuf_region(struct intel_context *intel)
  88 {
  89    struct intel_renderbuffer *irb
  90       = intel_renderbuffer(intel->ctx.ReadBuffer->_ColorReadBuffer);
  91    if (irb)
  92       return irb->region;
  93    else
  94       return NULL;
  95 }
  96
  97 void
  98 intel_get_cliprects(struct intel_context *intel,
  99                     struct drm_clip_rect **cliprects,
 100                     unsigned int *num_cliprects,
 101                     int *x_off, int *y_off)
 102 {
 103    __DRIdrawablePrivate *dPriv = intel->driDrawable;
 104
 105    if (intel->constant_cliprect) {
 106       /* FBO or DRI2 rendering, which can just use the fb's size. */
 107       intel->fboRect.x1 = 0;
 108       intel->fboRect.y1 = 0;
 109       intel->fboRect.x2 = intel->ctx.DrawBuffer->Width;
 110       intel->fboRect.y2 = intel->ctx.DrawBuffer->Height;
 111
 112       *cliprects = &intel->fboRect;
 113       *num_cliprects = 1;
 114       *x_off = 0;
 115       *y_off = 0;
 116    } else if (intel->front_cliprects || dPriv->numBackClipRects == 0) {
 117       /* use the front clip rects */
 118       *cliprects = dPriv->pClipRects;
 119       *num_cliprects = dPriv->numClipRects;
 120       *x_off = dPriv->x;
 121       *y_off = dPriv->y;
 122    }
 123    else {
 124       /* use the back clip rects */
 125       *num_cliprects = dPriv->numBackClipRects;
 126       *cliprects = dPriv->pBackClipRects;
 127       *x_off = dPriv->backX;
 128       *y_off = dPriv->backY;
 129    }
 130 }
 131
 132
 133 /**
 134  * Check if we're about to draw into the front color buffer.
 135  * If so, set the intel->front_buffer_dirty field to true.
 136  */
 137 void
 138 intel_check_front_buffer_rendering(struct intel_context *intel)
 139 {
 140    const struct gl_framebuffer *fb = intel->ctx.DrawBuffer;
 141    if (fb->Name == 0) {
 142       /* drawing to window system buffer */
 143       if (fb->_NumColorDrawBuffers > 0) {
 144          if (fb->_ColorDrawBufferIndexes[0] == BUFFER_FRONT_LEFT) {
 145             intel->front_buffer_dirty = GL_TRUE;
 146          }
 147       }
 148    }
 149 }
 150
 151
 152 /**
 153  * Update the hardware state for drawing into a window or framebuffer object.
 154  *
 155  * Called by glDrawBuffer, glBindFramebufferEXT, MakeCurrent, and other
 156  * places within the driver.
 157  *
 158  * Basically, this needs to be called any time the current framebuffer
 159  * changes, the renderbuffers change, or we need to draw into different
 160  * color buffers.
 161  */
 162 void
 163 intel_draw_buffer(GLcontext * ctx, struct gl_framebuffer *fb)
 164 {
 165    struct intel_context *intel = intel_context(ctx);
 166    struct intel_region *colorRegions[MAX_DRAW_BUFFERS], *depthRegion = NULL;
 167    struct intel_renderbuffer *irbDepth = NULL, *irbStencil = NULL;
 168
 169    if (!fb) {
 170       /* this can happen during the initial context initialization */
 171       return;
 172    }
 173
 174    /* Do this here, not core Mesa, since this function is called from
 175     * many places within the driver.
 176     */
 177    if (ctx->NewState & _NEW_BUFFERS) {
 178       /* this updates the DrawBuffer->_NumColorDrawBuffers fields, etc */
 179       _mesa_update_framebuffer(ctx);
 180       /* this updates the DrawBuffer's Width/Height if it's a FBO */
 181       _mesa_update_draw_buffer_bounds(ctx);
 182    }
 183
 184    if (fb->_Status != GL_FRAMEBUFFER_COMPLETE_EXT) {
 185       /* this may occur when we're called by glBindFrameBuffer() during
 186        * the process of someone setting up renderbuffers, etc.
 187        */
 188       /*_mesa_debug(ctx, "DrawBuffer: incomplete user FBO\n");*/
 189       return;
 190    }
 191
 192    /* How many color buffers are we drawing into?
 193     *
 194     * If there are zero buffers or the buffer is too big, don't configure any
 195     * regions for hardware drawing.  We'll fallback to software below.  Not
 196     * having regions set makes some of the software fallback paths faster.
 197     */
 198    if ((fb->Width > ctx->Const.MaxRenderbufferSize)
 199        || (fb->Height > ctx->Const.MaxRenderbufferSize)
 200        || (fb->_NumColorDrawBuffers == 0)) {
 201       /* writing to 0  */
 202       colorRegions[0] = NULL;
 203       intel->constant_cliprect = GL_TRUE;
 204    }
 205    else if (fb->_NumColorDrawBuffers > 1) {
 206        int i;
 207        struct intel_renderbuffer *irb;
 208
 209        for (i = 0; i < fb->_NumColorDrawBuffers; i++) {
 210            irb = intel_renderbuffer(fb->_ColorDrawBuffers[i]);
 211            colorRegions[i] = irb ? irb->region : NULL;
 212        }
 213        intel->constant_cliprect = GL_TRUE;
 214    }
 215    else {
 216       /* Get the intel_renderbuffer for the single colorbuffer we're drawing
 217        * into, and set up cliprects if it's a DRI1 window front buffer.
 218        */
 219       if (fb->Name == 0) {
 220          intel->constant_cliprect = intel->driScreen->dri2.enabled;
 221          /* drawing to window system buffer */
 222          if (fb->_ColorDrawBufferIndexes[0] == BUFFER_FRONT_LEFT) {
 223             if (!intel->constant_cliprect && !intel->front_cliprects)
 224                intel_batchbuffer_flush(intel->batch);
 225             intel->front_cliprects = GL_TRUE;
 226             colorRegions[0] = intel_get_rb_region(fb, BUFFER_FRONT_LEFT);
 227          }
 228          else {
 229             if (!intel->constant_cliprect && intel->front_cliprects)
 230                intel_batchbuffer_flush(intel->batch);
 231             intel->front_cliprects = GL_FALSE;
 232             colorRegions[0] = intel_get_rb_region(fb, BUFFER_BACK_LEFT);
 233          }
 234       }
 235       else {
 236          /* drawing to user-created FBO */
 237          struct intel_renderbuffer *irb;
 238          irb = intel_renderbuffer(fb->_ColorDrawBuffers[0]);
 239          colorRegions[0] = (irb && irb->region) ? irb->region : NULL;
 240          intel->constant_cliprect = GL_TRUE;
 241       }
 242    }
 243
 244    if (!colorRegions[0]) {
 245       FALLBACK(intel, INTEL_FALLBACK_DRAW_BUFFER, GL_TRUE);
 246    }
 247    else {
 248       FALLBACK(intel, INTEL_FALLBACK_DRAW_BUFFER, GL_FALSE);
 249    }
 250
 251    /***
 252     *** Get depth buffer region and check if we need a software fallback.
 253     *** Note that the depth buffer is usually a DEPTH_STENCIL buffer.
 254     ***/
 255    if (fb->_DepthBuffer && fb->_DepthBuffer->Wrapped) {
 256       irbDepth = intel_renderbuffer(fb->_DepthBuffer->Wrapped);
 257       if (irbDepth && irbDepth->region) {
 258          FALLBACK(intel, INTEL_FALLBACK_DEPTH_BUFFER, GL_FALSE);
 259          depthRegion = irbDepth->region;
 260       }
 261       else {
 262          FALLBACK(intel, INTEL_FALLBACK_DEPTH_BUFFER, GL_TRUE);
 263          depthRegion = NULL;
 264       }
 265    }
 266    else {
 267       /* not using depth buffer */
 268       FALLBACK(intel, INTEL_FALLBACK_DEPTH_BUFFER, GL_FALSE);
 269       depthRegion = NULL;
 270    }
 271
 272    /***
 273     *** Stencil buffer
 274     *** This can only be hardware accelerated if we're using a
 275     *** combined DEPTH_STENCIL buffer.
 276     ***/
 277    if (fb->_StencilBuffer && fb->_StencilBuffer->Wrapped) {
 278       irbStencil = intel_renderbuffer(fb->_StencilBuffer->Wrapped);
 279       if (irbStencil && irbStencil->region) {
 280          ASSERT(irbStencil->Base.Format == MESA_FORMAT_S8_Z24);
 281          FALLBACK(intel, INTEL_FALLBACK_STENCIL_BUFFER, GL_FALSE);
 282       }
 283       else {
 284          FALLBACK(intel, INTEL_FALLBACK_STENCIL_BUFFER, GL_TRUE);
 285       }
 286    }
 287    else {
 288       /* XXX FBO: instead of FALSE, pass ctx->Stencil._Enabled ??? */
 289       FALLBACK(intel, INTEL_FALLBACK_STENCIL_BUFFER, GL_FALSE);
 290    }
 291
 292    /*
 293     * Update depth and stencil test state
 294     */
 295    if (ctx->Driver.Enable) {
 296       ctx->Driver.Enable(ctx, GL_DEPTH_TEST,
 297                          (ctx->Depth.Test && fb->Visual.depthBits > 0));
 298       ctx->Driver.Enable(ctx, GL_STENCIL_TEST,
 299                          (ctx->Stencil.Enabled && fb->Visual.stencilBits > 0));
 300    }
 301    else {
 302       /* Mesa's Stencil._Enabled field is updated when
 303        * _NEW_BUFFERS | _NEW_STENCIL, but i965 code assumes that the value
 304        * only changes with _NEW_STENCIL (which seems sensible).  So flag it
 305        * here since this is the _NEW_BUFFERS path.
 306        */
 307       ctx->NewState |= (_NEW_DEPTH | _NEW_STENCIL);
 308    }
 309
 310    intel->vtbl.set_draw_region(intel, colorRegions, depthRegion,
 311                                fb->_NumColorDrawBuffers);
 312
 313    /* update viewport since it depends on window size */
 314 #ifdef I915
 315    intelCalcViewport(ctx);
 316 #else
 317    ctx->NewState |= _NEW_VIEWPORT;
 318 #endif
 319    /* Set state we know depends on drawable parameters:
 320     */
 321    if (ctx->Driver.Scissor)
 322       ctx->Driver.Scissor(ctx, ctx->Scissor.X, ctx->Scissor.Y,
 323                           ctx->Scissor.Width, ctx->Scissor.Height);
 324    intel->NewGLState |= _NEW_SCISSOR;
 325
 326    if (ctx->Driver.DepthRange)
 327       ctx->Driver.DepthRange(ctx,
 328                              ctx->Viewport.Near,
 329                              ctx->Viewport.Far);
 330
 331    /* Update culling direction which changes depending on the
 332     * orientation of the buffer:
 333     */
 334    if (ctx->Driver.FrontFace)
 335       ctx->Driver.FrontFace(ctx, ctx->Polygon.FrontFace);
 336    else
 337       ctx->NewState |= _NEW_POLYGON;
 338 }
 339
 340
 341 static void
 342 intelDrawBuffer(GLcontext * ctx, GLenum mode)
 343 {
 344    if ((ctx->DrawBuffer != NULL) && (ctx->DrawBuffer->Name == 0)) {
 345       struct intel_context *const intel = intel_context(ctx);
 346       const GLboolean was_front_buffer_rendering =
 347         intel->is_front_buffer_rendering;
 348
 349       intel->is_front_buffer_rendering = (mode == GL_FRONT_LEFT)
 350         || (mode == GL_FRONT);
 351
 352       /* If we weren't front-buffer rendering before but we are now, make sure
 353        * that the front-buffer has actually been allocated.
 354        */
 355       if (!was_front_buffer_rendering && intel->is_front_buffer_rendering) {
 356          intel_update_renderbuffers(intel->driContext,
 357                                     intel->driContext->driDrawablePriv);
 358       }
 359    }
 360
 361    intel_draw_buffer(ctx, ctx->DrawBuffer);
 362 }
 363
 364
 365 static void
 366 intelReadBuffer(GLcontext * ctx, GLenum mode)
 367 {
 368    if ((ctx->DrawBuffer != NULL) && (ctx->DrawBuffer->Name == 0)) {
 369       struct intel_context *const intel = intel_context(ctx);
 370       const GLboolean was_front_buffer_reading =
 371         intel->is_front_buffer_reading;
 372
 373       intel->is_front_buffer_reading = (mode == GL_FRONT_LEFT)
 374         || (mode == GL_FRONT);
 375
 376       /* If we weren't front-buffer reading before but we are now, make sure
 377        * that the front-buffer has actually been allocated.
 378        */
 379       if (!was_front_buffer_reading && intel->is_front_buffer_reading) {
 380          intel_update_renderbuffers(intel->driContext,
 381                                     intel->driContext->driDrawablePriv);
 382       }
 383    }
 384
 385    if (ctx->ReadBuffer == ctx->DrawBuffer) {
 386       /* This will update FBO completeness status.
 387        * A framebuffer will be incomplete if the GL_READ_BUFFER setting
 388        * refers to a missing renderbuffer.  Calling glReadBuffer can set
 389        * that straight and can make the drawing buffer complete.
 390        */
 391       intel_draw_buffer(ctx, ctx->DrawBuffer);
 392    }
 393    /* Generally, functions which read pixels (glReadPixels, glCopyPixels, etc)
 394     * reference ctx->ReadBuffer and do appropriate state checks.
 395     */
 396 }
 397
 398
 399 void
 400 intelInitBufferFuncs(struct dd_function_table *functions)
 401 {
 402    functions->DrawBuffer = intelDrawBuffer;
 403    functions->ReadBuffer = intelReadBuffer;
 404 }