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_regions.h"
  32 #include "intel_batchbuffer.h"
  33 #include "main/framebuffer.h"
  34 #include "drirenderbuffer.h"
  35
  36
  37 /**
  38  * XXX move this into a new dri/common/cliprects.c file.
  39  */
  40 GLboolean
  41 intel_intersect_cliprects(drm_clip_rect_t * dst,
  42                           const drm_clip_rect_t * a,
  43                           const drm_clip_rect_t * b)
  44 {
  45    GLint bx = b->x1;
  46    GLint by = b->y1;
  47    GLint bw = b->x2 - bx;
  48    GLint bh = b->y2 - by;
  49
  50    if (bx < a->x1)
  51       bw -= a->x1 - bx, bx = a->x1;
  52    if (by < a->y1)
  53       bh -= a->y1 - by, by = a->y1;
  54    if (bx + bw > a->x2)
  55       bw = a->x2 - bx;
  56    if (by + bh > a->y2)
  57       bh = a->y2 - by;
  58    if (bw <= 0)
  59       return GL_FALSE;
  60    if (bh <= 0)
  61       return GL_FALSE;
  62
  63    dst->x1 = bx;
  64    dst->y1 = by;
  65    dst->x2 = bx + bw;
  66    dst->y2 = by + bh;
  67
  68    return GL_TRUE;
  69 }
  70
  71 /**
  72  * Return pointer to current color drawing region, or NULL.
  73  */
  74 struct intel_region *
  75 intel_drawbuf_region(struct intel_context *intel)
  76 {
  77    struct intel_renderbuffer *irbColor =
  78       intel_renderbuffer(intel->ctx.DrawBuffer->_ColorDrawBuffers[0]);
  79    if (irbColor)
  80       return irbColor->region;
  81    else
  82       return NULL;
  83 }
  84
  85 /**
  86  * Return pointer to current color reading region, or NULL.
  87  */
  88 struct intel_region *
  89 intel_readbuf_region(struct intel_context *intel)
  90 {
  91    struct intel_renderbuffer *irb
  92       = intel_renderbuffer(intel->ctx.ReadBuffer->_ColorReadBuffer);
  93    if (irb)
  94       return irb->region;
  95    else
  96       return NULL;
  97 }
  98
  99 void
 100 intel_get_cliprects(struct intel_context *intel,
 101                     struct drm_clip_rect **cliprects,
 102                     unsigned int *num_cliprects,
 103                     int *x_off, int *y_off)
 104 {
 105    __DRIdrawablePrivate *dPriv = intel->driDrawable;
 106
 107    if (intel->constant_cliprect) {
 108       /* FBO or DRI2 rendering, which can just use the fb's size. */
 109       intel->fboRect.x1 = 0;
 110       intel->fboRect.y1 = 0;
 111       intel->fboRect.x2 = intel->ctx.DrawBuffer->Width;
 112       intel->fboRect.y2 = intel->ctx.DrawBuffer->Height;
 113
 114       *cliprects = &intel->fboRect;
 115       *num_cliprects = 1;
 116       *x_off = 0;
 117       *y_off = 0;
 118    } else if (intel->front_cliprects || dPriv->numBackClipRects == 0) {
 119       /* use the front clip rects */
 120       *cliprects = dPriv->pClipRects;
 121       *num_cliprects = dPriv->numClipRects;
 122       *x_off = dPriv->x;
 123       *y_off = dPriv->y;
 124    }
 125    else {
 126       /* use the back clip rects */
 127       *num_cliprects = dPriv->numBackClipRects;
 128       *cliprects = dPriv->pBackClipRects;
 129       *x_off = dPriv->backX;
 130       *y_off = dPriv->backY;
 131    }
 132 }
 133
 134
 135 /**
 136  * Update the hardware state for drawing into a window or framebuffer object.
 137  *
 138  * Called by glDrawBuffer, glBindFramebufferEXT, MakeCurrent, and other
 139  * places within the driver.
 140  *
 141  * Basically, this needs to be called any time the current framebuffer
 142  * changes, the renderbuffers change, or we need to draw into different
 143  * color buffers.
 144  */
 145 void
 146 intel_draw_buffer(GLcontext * ctx, struct gl_framebuffer *fb)
 147 {
 148    struct intel_context *intel = intel_context(ctx);
 149    struct intel_region *colorRegions[MAX_DRAW_BUFFERS], *depthRegion = NULL;
 150    struct intel_renderbuffer *irbDepth = NULL, *irbStencil = NULL;
 151
 152    if (!fb) {
 153       /* this can happen during the initial context initialization */
 154       return;
 155    }
 156
 157    /* Do this here, not core Mesa, since this function is called from
 158     * many places within the driver.
 159     */
 160    if (ctx->NewState & _NEW_BUFFERS) {
 161       /* this updates the DrawBuffer->_NumColorDrawBuffers fields, etc */
 162       _mesa_update_framebuffer(ctx);
 163       /* this updates the DrawBuffer's Width/Height if it's a FBO */
 164       _mesa_update_draw_buffer_bounds(ctx);
 165    }
 166
 167    if (fb->_Status != GL_FRAMEBUFFER_COMPLETE_EXT) {
 168       /* this may occur when we're called by glBindFrameBuffer() during
 169        * the process of someone setting up renderbuffers, etc.
 170        */
 171       /*_mesa_debug(ctx, "DrawBuffer: incomplete user FBO\n");*/
 172       return;
 173    }
 174
 175    /*
 176     * How many color buffers are we drawing into?
 177     */
 178    if (fb->_NumColorDrawBuffers == 0) {
 179       /* writing to 0  */
 180       colorRegions[0] = NULL;
 181       intel->constant_cliprect = GL_TRUE;
 182    }
 183    else if (fb->_NumColorDrawBuffers > 1) {
 184        int i;
 185        struct intel_renderbuffer *irb;
 186
 187        for (i = 0; i < fb->_NumColorDrawBuffers; i++) {
 188            irb = intel_renderbuffer(fb->_ColorDrawBuffers[i]);
 189            colorRegions[i] = irb ? irb->region : NULL;
 190        }
 191        intel->constant_cliprect = GL_TRUE;
 192    }
 193    else {
 194       /* Get the intel_renderbuffer for the single colorbuffer we're drawing
 195        * into, and set up cliprects if it's .
 196        */
 197       if (fb->Name == 0) {
 198          intel->constant_cliprect = intel->driScreen->dri2.enabled;
 199          /* drawing to window system buffer */
 200          if (fb->_ColorDrawBufferIndexes[0] == BUFFER_FRONT_LEFT) {
 201             if (!intel->constant_cliprect && !intel->front_cliprects)
 202                intel_batchbuffer_flush(intel->batch);
 203             intel->front_cliprects = GL_TRUE;
 204             colorRegions[0] = intel_get_rb_region(fb, BUFFER_FRONT_LEFT);
 205
 206             intel->front_buffer_dirty = GL_TRUE;
 207          }
 208          else {
 209             if (!intel->constant_cliprect && intel->front_cliprects)
 210                intel_batchbuffer_flush(intel->batch);
 211             intel->front_cliprects = GL_FALSE;
 212             colorRegions[0]= intel_get_rb_region(fb, BUFFER_BACK_LEFT);
 213          }
 214       }
 215       else {
 216          /* drawing to user-created FBO */
 217          struct intel_renderbuffer *irb;
 218          irb = intel_renderbuffer(fb->_ColorDrawBuffers[0]);
 219          colorRegions[0] = (irb && irb->region) ? irb->region : NULL;
 220          intel->constant_cliprect = GL_TRUE;
 221       }
 222    }
 223
 224    if (!colorRegions[0]) {
 225       FALLBACK(intel, INTEL_FALLBACK_DRAW_BUFFER, GL_TRUE);
 226    }
 227    else {
 228       FALLBACK(intel, INTEL_FALLBACK_DRAW_BUFFER, GL_FALSE);
 229    }
 230
 231    /***
 232     *** Get depth buffer region and check if we need a software fallback.
 233     *** Note that the depth buffer is usually a DEPTH_STENCIL buffer.
 234     ***/
 235    if (fb->_DepthBuffer && fb->_DepthBuffer->Wrapped) {
 236       irbDepth = intel_renderbuffer(fb->_DepthBuffer->Wrapped);
 237       if (irbDepth && irbDepth->region) {
 238          FALLBACK(intel, INTEL_FALLBACK_DEPTH_BUFFER, GL_FALSE);
 239          depthRegion = irbDepth->region;
 240       }
 241       else {
 242          FALLBACK(intel, INTEL_FALLBACK_DEPTH_BUFFER, GL_TRUE);
 243          depthRegion = NULL;
 244       }
 245    }
 246    else {
 247       /* not using depth buffer */
 248       FALLBACK(intel, INTEL_FALLBACK_DEPTH_BUFFER, GL_FALSE);
 249       depthRegion = NULL;
 250    }
 251
 252    /***
 253     *** Stencil buffer
 254     *** This can only be hardware accelerated if we're using a
 255     *** combined DEPTH_STENCIL buffer.
 256     ***/
 257    if (fb->_StencilBuffer && fb->_StencilBuffer->Wrapped) {
 258       irbStencil = intel_renderbuffer(fb->_StencilBuffer->Wrapped);
 259       if (irbStencil && irbStencil->region) {
 260          ASSERT(irbStencil->Base._ActualFormat == GL_DEPTH24_STENCIL8_EXT);
 261          FALLBACK(intel, INTEL_FALLBACK_STENCIL_BUFFER, GL_FALSE);
 262       }
 263       else {
 264          FALLBACK(intel, INTEL_FALLBACK_STENCIL_BUFFER, GL_TRUE);
 265       }
 266    }
 267    else {
 268       /* XXX FBO: instead of FALSE, pass ctx->Stencil._Enabled ??? */
 269       FALLBACK(intel, INTEL_FALLBACK_STENCIL_BUFFER, GL_FALSE);
 270    }
 271
 272    /*
 273     * Update depth and stencil test state
 274     */
 275    if (ctx->Driver.Enable) {
 276       ctx->Driver.Enable(ctx, GL_DEPTH_TEST,
 277                          (ctx->Depth.Test && fb->Visual.depthBits > 0));
 278       ctx->Driver.Enable(ctx, GL_STENCIL_TEST,
 279                          (ctx->Stencil.Enabled && fb->Visual.stencilBits > 0));
 280    }
 281    else {
 282       /* Mesa's Stencil._Enabled field is updated when
 283        * _NEW_BUFFERS | _NEW_STENCIL, but i965 code assumes that the value
 284        * only changes with _NEW_STENCIL (which seems sensible).  So flag it
 285        * here since this is the _NEW_BUFFERS path.
 286        */
 287       ctx->NewState |= (_NEW_DEPTH | _NEW_STENCIL);
 288    }
 289
 290    intel->vtbl.set_draw_region(intel, colorRegions, depthRegion,
 291                                fb->_NumColorDrawBuffers);
 292
 293    /* update viewport since it depends on window size */
 294 #ifdef I915
 295    intelCalcViewport(ctx);
 296 #else
 297    ctx->NewState |= _NEW_VIEWPORT;
 298 #endif
 299    /* Set state we know depends on drawable parameters:
 300     */
 301    if (ctx->Driver.Scissor)
 302       ctx->Driver.Scissor(ctx, ctx->Scissor.X, ctx->Scissor.Y,
 303                           ctx->Scissor.Width, ctx->Scissor.Height);
 304    intel->NewGLState |= _NEW_SCISSOR;
 305
 306    if (ctx->Driver.DepthRange)
 307       ctx->Driver.DepthRange(ctx,
 308                              ctx->Viewport.Near,
 309                              ctx->Viewport.Far);
 310
 311    /* Update culling direction which changes depending on the
 312     * orientation of the buffer:
 313     */
 314    if (ctx->Driver.FrontFace)
 315       ctx->Driver.FrontFace(ctx, ctx->Polygon.FrontFace);
 316    else
 317       ctx->NewState |= _NEW_POLYGON;
 318 }
 319
 320
 321 static void
 322 intelDrawBuffer(GLcontext * ctx, GLenum mode)
 323 {
 324    if ((ctx->DrawBuffer != NULL) && (ctx->DrawBuffer->Name == 0)) {
 325       struct intel_context *const intel = intel_context(ctx);
 326       const GLboolean was_front_buffer_rendering =
 327         intel->is_front_buffer_rendering;
 328
 329       intel->is_front_buffer_rendering = (mode == GL_FRONT_LEFT)
 330         || (mode == GL_FRONT);
 331
 332       /* If we weren't front-buffer rendering before but we are now, make sure
 333        * that the front-buffer has actually been allocated.
 334        */
 335       if (!was_front_buffer_rendering && intel->is_front_buffer_rendering) {
 336          intel_update_renderbuffers(intel->driContext,
 337                                     intel->driContext->driDrawablePriv);
 338       }
 339    }
 340
 341    intel_draw_buffer(ctx, ctx->DrawBuffer);
 342 }
 343
 344
 345 static void
 346 intelReadBuffer(GLcontext * ctx, GLenum mode)
 347 {
 348    if ((ctx->DrawBuffer != NULL) && (ctx->DrawBuffer->Name == 0)) {
 349       struct intel_context *const intel = intel_context(ctx);
 350       const GLboolean was_front_buffer_reading =
 351         intel->is_front_buffer_reading;
 352
 353       intel->is_front_buffer_reading = (mode == GL_FRONT_LEFT)
 354         || (mode == GL_FRONT);
 355
 356       /* If we weren't front-buffer reading before but we are now, make sure
 357        * that the front-buffer has actually been allocated.
 358        */
 359       if (!was_front_buffer_reading && intel->is_front_buffer_reading) {
 360          intel_update_renderbuffers(intel->driContext,
 361                                     intel->driContext->driDrawablePriv);
 362       }
 363    }
 364
 365    if (ctx->ReadBuffer == ctx->DrawBuffer) {
 366       /* This will update FBO completeness status.
 367        * A framebuffer will be incomplete if the GL_READ_BUFFER setting
 368        * refers to a missing renderbuffer.  Calling glReadBuffer can set
 369        * that straight and can make the drawing buffer complete.
 370        */
 371       intel_draw_buffer(ctx, ctx->DrawBuffer);
 372    }
 373    /* Generally, functions which read pixels (glReadPixels, glCopyPixels, etc)
 374     * reference ctx->ReadBuffer and do appropriate state checks.
 375     */
 376 }
 377
 378
 379 void
 380 intelInitBufferFuncs(struct dd_function_table *functions)
 381 {
 382    functions->DrawBuffer = intelDrawBuffer;
 383    functions->ReadBuffer = intelReadBuffer;
 384 }