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    intel->fboRect.x1 = 0;
 106    intel->fboRect.y1 = 0;
 107    intel->fboRect.x2 = intel->ctx.DrawBuffer->Width;
 108    intel->fboRect.y2 = intel->ctx.DrawBuffer->Height;
 109
 110    *cliprects = &intel->fboRect;
 111    *num_cliprects = 1;
 112    *x_off = 0;
 113    *y_off = 0;
 114 }
 115
 116
 117 /**
 118  * Check if we're about to draw into the front color buffer.
 119  * If so, set the intel->front_buffer_dirty field to true.
 120  */
 121 void
 122 intel_check_front_buffer_rendering(struct intel_context *intel)
 123 {
 124    const struct gl_framebuffer *fb = intel->ctx.DrawBuffer;
 125    if (fb->Name == 0) {
 126       /* drawing to window system buffer */
 127       if (fb->_NumColorDrawBuffers > 0) {
 128          if (fb->_ColorDrawBufferIndexes[0] == BUFFER_FRONT_LEFT) {
 129             intel->front_buffer_dirty = GL_TRUE;
 130          }
 131       }
 132    }
 133 }
 134
 135
 136 /**
 137  * Update the hardware state for drawing into a window or framebuffer object.
 138  *
 139  * Called by glDrawBuffer, glBindFramebufferEXT, MakeCurrent, and other
 140  * places within the driver.
 141  *
 142  * Basically, this needs to be called any time the current framebuffer
 143  * changes, the renderbuffers change, or we need to draw into different
 144  * color buffers.
 145  */
 146 void
 147 intel_draw_buffer(GLcontext * ctx, struct gl_framebuffer *fb)
 148 {
 149    struct intel_context *intel = intel_context(ctx);
 150    struct intel_region *colorRegions[MAX_DRAW_BUFFERS], *depthRegion = NULL;
 151    struct intel_renderbuffer *irbDepth = NULL, *irbStencil = NULL;
 152
 153    if (!fb) {
 154       /* this can happen during the initial context initialization */
 155       return;
 156    }
 157
 158    /* Do this here, not core Mesa, since this function is called from
 159     * many places within the driver.
 160     */
 161    if (ctx->NewState & _NEW_BUFFERS) {
 162       /* this updates the DrawBuffer->_NumColorDrawBuffers fields, etc */
 163       _mesa_update_framebuffer(ctx);
 164       /* this updates the DrawBuffer's Width/Height if it's a FBO */
 165       _mesa_update_draw_buffer_bounds(ctx);
 166    }
 167
 168    if (fb->_Status != GL_FRAMEBUFFER_COMPLETE_EXT) {
 169       /* this may occur when we're called by glBindFrameBuffer() during
 170        * the process of someone setting up renderbuffers, etc.
 171        */
 172       /*_mesa_debug(ctx, "DrawBuffer: incomplete user FBO\n");*/
 173       return;
 174    }
 175
 176    /* How many color buffers are we drawing into?
 177     *
 178     * If there are zero buffers or the buffer is too big, don't configure any
 179     * regions for hardware drawing.  We'll fallback to software below.  Not
 180     * having regions set makes some of the software fallback paths faster.
 181     */
 182    if ((fb->Width > ctx->Const.MaxRenderbufferSize)
 183        || (fb->Height > ctx->Const.MaxRenderbufferSize)
 184        || (fb->_NumColorDrawBuffers == 0)) {
 185       /* writing to 0  */
 186       colorRegions[0] = NULL;
 187    }
 188    else if (fb->_NumColorDrawBuffers > 1) {
 189        int i;
 190        struct intel_renderbuffer *irb;
 191
 192        for (i = 0; i < fb->_NumColorDrawBuffers; i++) {
 193            irb = intel_renderbuffer(fb->_ColorDrawBuffers[i]);
 194            colorRegions[i] = irb ? irb->region : NULL;
 195        }
 196    }
 197    else {
 198       /* Get the intel_renderbuffer for the single colorbuffer we're drawing
 199        * into.
 200        */
 201       if (fb->Name == 0) {
 202          /* drawing to window system buffer */
 203          if (fb->_ColorDrawBufferIndexes[0] == BUFFER_FRONT_LEFT)
 204             colorRegions[0] = intel_get_rb_region(fb, BUFFER_FRONT_LEFT);
 205          else
 206             colorRegions[0] = intel_get_rb_region(fb, BUFFER_BACK_LEFT);
 207       }
 208       else {
 209          /* drawing to user-created FBO */
 210          struct intel_renderbuffer *irb;
 211          irb = intel_renderbuffer(fb->_ColorDrawBuffers[0]);
 212          colorRegions[0] = (irb && irb->region) ? irb->region : NULL;
 213       }
 214    }
 215
 216    if (!colorRegions[0]) {
 217       FALLBACK(intel, INTEL_FALLBACK_DRAW_BUFFER, GL_TRUE);
 218    }
 219    else {
 220       FALLBACK(intel, INTEL_FALLBACK_DRAW_BUFFER, GL_FALSE);
 221    }
 222
 223    /***
 224     *** Get depth buffer region and check if we need a software fallback.
 225     *** Note that the depth buffer is usually a DEPTH_STENCIL buffer.
 226     ***/
 227    if (fb->_DepthBuffer && fb->_DepthBuffer->Wrapped) {
 228       irbDepth = intel_renderbuffer(fb->_DepthBuffer->Wrapped);
 229       if (irbDepth && irbDepth->region) {
 230          FALLBACK(intel, INTEL_FALLBACK_DEPTH_BUFFER, GL_FALSE);
 231          depthRegion = irbDepth->region;
 232       }
 233       else {
 234          FALLBACK(intel, INTEL_FALLBACK_DEPTH_BUFFER, GL_TRUE);
 235          depthRegion = NULL;
 236       }
 237    }
 238    else {
 239       /* not using depth buffer */
 240       FALLBACK(intel, INTEL_FALLBACK_DEPTH_BUFFER, GL_FALSE);
 241       depthRegion = NULL;
 242    }
 243
 244    /***
 245     *** Stencil buffer
 246     *** This can only be hardware accelerated if we're using a
 247     *** combined DEPTH_STENCIL buffer.
 248     ***/
 249    if (fb->_StencilBuffer && fb->_StencilBuffer->Wrapped) {
 250       irbStencil = intel_renderbuffer(fb->_StencilBuffer->Wrapped);
 251       if (irbStencil && irbStencil->region) {
 252          ASSERT(irbStencil->Base.Format == MESA_FORMAT_S8_Z24);
 253          FALLBACK(intel, INTEL_FALLBACK_STENCIL_BUFFER, GL_FALSE);
 254       }
 255       else {
 256          FALLBACK(intel, INTEL_FALLBACK_STENCIL_BUFFER, GL_TRUE);
 257       }
 258    }
 259    else {
 260       /* XXX FBO: instead of FALSE, pass ctx->Stencil._Enabled ??? */
 261       FALLBACK(intel, INTEL_FALLBACK_STENCIL_BUFFER, GL_FALSE);
 262    }
 263
 264    /* If we have a (packed) stencil buffer attached but no depth buffer,
 265     * we still need to set up the shared depth/stencil state so we can use it.
 266     */
 267    if (depthRegion == NULL && irbStencil && irbStencil->region)
 268       depthRegion = irbStencil->region;
 269
 270    /*
 271     * Update depth and stencil test state
 272     */
 273    if (ctx->Driver.Enable) {
 274       ctx->Driver.Enable(ctx, GL_DEPTH_TEST,
 275                          (ctx->Depth.Test && fb->Visual.depthBits > 0));
 276       ctx->Driver.Enable(ctx, GL_STENCIL_TEST,
 277                          (ctx->Stencil.Enabled && fb->Visual.stencilBits > 0));
 278    }
 279    else {
 280       /* Mesa's Stencil._Enabled field is updated when
 281        * _NEW_BUFFERS | _NEW_STENCIL, but i965 code assumes that the value
 282        * only changes with _NEW_STENCIL (which seems sensible).  So flag it
 283        * here since this is the _NEW_BUFFERS path.
 284        */
 285       ctx->NewState |= (_NEW_DEPTH | _NEW_STENCIL);
 286    }
 287
 288    intel->vtbl.set_draw_region(intel, colorRegions, depthRegion,
 289                                fb->_NumColorDrawBuffers);
 290
 291    /* update viewport since it depends on window size */
 292 #ifdef I915
 293    intelCalcViewport(ctx);
 294 #else
 295    ctx->NewState |= _NEW_VIEWPORT;
 296 #endif
 297    /* Set state we know depends on drawable parameters:
 298     */
 299    if (ctx->Driver.Scissor)
 300       ctx->Driver.Scissor(ctx, ctx->Scissor.X, ctx->Scissor.Y,
 301                           ctx->Scissor.Width, ctx->Scissor.Height);
 302    intel->NewGLState |= _NEW_SCISSOR;
 303
 304    if (ctx->Driver.DepthRange)
 305       ctx->Driver.DepthRange(ctx,
 306                              ctx->Viewport.Near,
 307                              ctx->Viewport.Far);
 308
 309    /* Update culling direction which changes depending on the
 310     * orientation of the buffer:
 311     */
 312    if (ctx->Driver.FrontFace)
 313       ctx->Driver.FrontFace(ctx, ctx->Polygon.FrontFace);
 314    else
 315       ctx->NewState |= _NEW_POLYGON;
 316 }
 317
 318
 319 static void
 320 intelDrawBuffer(GLcontext * ctx, GLenum mode)
 321 {
 322    if ((ctx->DrawBuffer != NULL) && (ctx->DrawBuffer->Name == 0)) {
 323       struct intel_context *const intel = intel_context(ctx);
 324       const GLboolean was_front_buffer_rendering =
 325         intel->is_front_buffer_rendering;
 326
 327       intel->is_front_buffer_rendering = (mode == GL_FRONT_LEFT)
 328         || (mode == GL_FRONT);
 329
 330       /* If we weren't front-buffer rendering before but we are now, make sure
 331        * that the front-buffer has actually been allocated.
 332        */
 333       if (!was_front_buffer_rendering && intel->is_front_buffer_rendering) {
 334          intel_update_renderbuffers(intel->driContext,
 335                                     intel->driContext->driDrawablePriv);
 336       }
 337    }
 338
 339    intel_draw_buffer(ctx, ctx->DrawBuffer);
 340 }
 341
 342
 343 static void
 344 intelReadBuffer(GLcontext * ctx, GLenum mode)
 345 {
 346    if ((ctx->DrawBuffer != NULL) && (ctx->DrawBuffer->Name == 0)) {
 347       struct intel_context *const intel = intel_context(ctx);
 348       const GLboolean was_front_buffer_reading =
 349         intel->is_front_buffer_reading;
 350
 351       intel->is_front_buffer_reading = (mode == GL_FRONT_LEFT)
 352         || (mode == GL_FRONT);
 353
 354       /* If we weren't front-buffer reading before but we are now, make sure
 355        * that the front-buffer has actually been allocated.
 356        */
 357       if (!was_front_buffer_reading && intel->is_front_buffer_reading) {
 358          intel_update_renderbuffers(intel->driContext,
 359                                     intel->driContext->driDrawablePriv);
 360       }
 361    }
 362
 363    if (ctx->ReadBuffer == ctx->DrawBuffer) {
 364       /* This will update FBO completeness status.
 365        * A framebuffer will be incomplete if the GL_READ_BUFFER setting
 366        * refers to a missing renderbuffer.  Calling glReadBuffer can set
 367        * that straight and can make the drawing buffer complete.
 368        */
 369       intel_draw_buffer(ctx, ctx->DrawBuffer);
 370    }
 371    /* Generally, functions which read pixels (glReadPixels, glCopyPixels, etc)
 372     * reference ctx->ReadBuffer and do appropriate state checks.
 373     */
 374 }
 375
 376
 377 void
 378 intelInitBufferFuncs(struct dd_function_table *functions)
 379 {
 380    functions->DrawBuffer = intelDrawBuffer;
 381    functions->ReadBuffer = intelReadBuffer;
 382 }