diff --git a/cogl/cogl-context.c b/cogl/cogl-context.c index fa8a4b1bd..4b5b15e36 100644 --- a/cogl/cogl-context.c +++ b/cogl/cogl-context.c @@ -167,6 +167,7 @@ cogl_create_context (void) _context->logged_vertices = g_array_new (FALSE, FALSE, sizeof (GLfloat)); _context->journal_flush_attributes_array = g_array_new (TRUE, FALSE, sizeof (CoglVertexAttribute *)); + _context->journal_clip_bounds = NULL; _context->polygon_vertices = g_array_new (FALSE, FALSE, sizeof (float)); @@ -314,6 +315,8 @@ _cogl_destroy_context (void) g_array_free (_context->logged_vertices, TRUE); if (_context->journal_flush_attributes_array) g_array_free (_context->journal_flush_attributes_array, TRUE); + if (_context->journal_clip_bounds) + g_array_free (_context->journal_clip_bounds, TRUE); if (_context->polygon_vertices) g_array_free (_context->polygon_vertices, TRUE); diff --git a/cogl/cogl-context.h b/cogl/cogl-context.h index a3263558e..5511ed835 100644 --- a/cogl/cogl-context.h +++ b/cogl/cogl-context.h @@ -103,6 +103,7 @@ typedef struct GArray *logged_vertices; GArray *journal_flush_attributes_array; size_t journal_needed_vbo_len; + GArray *journal_clip_bounds; GArray *polygon_vertices; diff --git a/cogl/cogl-journal-private.h b/cogl/cogl-journal-private.h index 0da86ff9e..a34a5263e 100644 --- a/cogl/cogl-journal-private.h +++ b/cogl/cogl-journal-private.h @@ -36,6 +36,8 @@ typedef struct _CoglJournalEntry int n_layers; CoglMatrix model_view; CoglClipStack *clip_stack; + /* Offset into ctx->logged_vertices */ + size_t array_offset; /* XXX: These entries are pretty big now considering the padding in * CoglPipelineFlushOptions and CoglMatrix, so we might need to optimize this * later. */ diff --git a/cogl/cogl-journal.c b/cogl/cogl-journal.c index ad12a4219..210043b25 100644 --- a/cogl/cogl-journal.c +++ b/cogl/cogl-journal.c @@ -85,6 +85,11 @@ (POS_STRIDE + COLOR_STRIDE + \ TEX_STRIDE * (N_LAYERS < MIN_LAYER_PADING ? MIN_LAYER_PADING : N_LAYERS)) +/* If a batch is longer than this threshold then we'll assume it's not + worth doing software clipping and it's cheaper to program the GPU + to do the clip */ +#define COGL_JOURNAL_HARDWARE_CLIP_THRESHOLD 8 + typedef struct _CoglJournalFlushState { CoglVertexArray *vertex_array; @@ -685,6 +690,337 @@ _cogl_journal_flush_clip_stacks_and_entries (CoglJournalEntry *batch_start, time_flush_clip_stack_pipeline_entries); } +static gboolean +calculate_translation (const CoglMatrix *a, + const CoglMatrix *b, + float *tx_p, + float *ty_p) +{ + float tx, ty; + int x, y; + + /* Assuming we had the original matrix in this form: + * + * [ a₁₁, a₁₂, a₁₃, a₁₄ ] + * [ a₂₁, a₂₂, a₂₃, a₂₄ ] + * a = [ a₃₁, a₃₂, a₃₃, a₃₄ ] + * [ a₄₁, a₄₂, a₄₃, a₄₄ ] + * + * then a translation of that matrix would be a multiplication by a + * matrix of this form: + * + * [ 1, 0, 0, x ] + * [ 0, 1, 0, y ] + * t = [ 0, 0, 1, 0 ] + * [ 0, 0, 0, 1 ] + * + * That would give us a matrix of this form. + * + * [ a₁₁, a₁₂, a₁₃, a₁₁ x + a₁₂ y + a₁₄ ] + * [ a₂₁, a₂₂, a₂₃, a₂₁ x + a₂₂ y + a₂₄ ] + * b = a ⋅ t = [ a₃₁, a₃₂, a₃₃, a₃₁ x + a₃₂ y + a₃₄ ] + * [ a₄₁, a₄₂, a₄₃, a₄₁ x + a₄₂ y + a₄₄ ] + * + * We can use the two equations from the top left of the matrix to + * work out the x and y translation given the two matrices: + * + * b₁₄ = a₁₁x + a₁₂y + a₁₄ + * b₂₄ = a₂₁x + a₂₂y + a₂₄ + * + * Rearranging gives us: + * + * a₁₂ b₂₄ - a₂₄ a₁₂ + * ----------------- + a₁₄ - b₁₄ + * a₂₂ + * x = --------------------------------- + * a₁₂ a₂₁ + * ------- - a₁₁ + * a₂₂ + * + * b₂₄ - a₂₁x - a₂₄ + * y = ---------------- + * a₂₂ + * + * Once we've worked out what x and y would be if this was a valid + * translation then we can simply verify that the rest of the matrix + * matches up. + */ + + /* The leftmost 3x4 part of the matrix shouldn't change by a + translation so we can just compare it directly */ + for (y = 0; y < 4; y++) + for (x = 0; x < 3; x++) + if ((&a->xx)[x * 4 + y] != (&b->xx)[x * 4 + y]) + return FALSE; + + tx = (((a->xy * b->yw - a->yw * a->xy) / a->yy + a->xw - b->xw) / + ((a->xy * a->yx) / a->yy - a->xx)); + ty = (b->yw - a->yx * tx - a->yw) / a->yy; + +#define APPROX_EQUAL(a, b) (fabsf ((a) - (b)) < 1e-6f) + + /* Check whether the 4th column of the matrices match up to the + calculation */ + if (!APPROX_EQUAL (b->xw, a->xx * tx + a->xy * ty + a->xw) || + !APPROX_EQUAL (b->yw, a->yx * tx + a->yy * ty + a->yw) || + !APPROX_EQUAL (b->zw, a->zx * tx + a->zy * ty + a->zw) || + !APPROX_EQUAL (b->ww, a->wx * tx + a->wy * ty + a->ww)) + return FALSE; + +#undef APPROX_EQUAL + + *tx_p = tx; + *ty_p = ty; + + return TRUE; +} + +typedef struct +{ + float x_1, y_1; + float x_2, y_2; +} ClipBounds; + +static void +check_software_clip_for_batch (CoglJournalEntry *batch_start, + int batch_len, + CoglJournalFlushState *state) +{ + CoglClipStack *clip_stack, *clip_entry; + int entry_num; + + _COGL_GET_CONTEXT (ctx, NO_RETVAL); + + /* This tries to find cases where the entry is logged with a clip + but it would be faster to modify the vertex and texture + coordinates rather than flush the clip so that it can batch + better */ + + /* If the batch is reasonably long then it's worthwhile programming + the GPU to do the clip */ + if (batch_len >= COGL_JOURNAL_HARDWARE_CLIP_THRESHOLD) + return; + + clip_stack = batch_start->clip_stack; + + if (clip_stack == NULL) + return; + + /* Verify that all of the clip stack entries are a simple rectangle + clip */ + for (clip_entry = clip_stack; clip_entry; clip_entry = clip_entry->parent) + if (clip_entry->type != COGL_CLIP_STACK_RECT) + return; + + /* This scratch buffer is used to store the translation for each + entry in the journal. We store it in a separate buffer because + it's expensive to calculate but at this point we still don't know + whether we can clip all of the entries so we don't want to do the + rest of the dependant calculations until we're sure we can. */ + if (ctx->journal_clip_bounds == NULL) + ctx->journal_clip_bounds = g_array_new (FALSE, FALSE, sizeof (ClipBounds)); + g_array_set_size (ctx->journal_clip_bounds, batch_len); + + for (entry_num = 0; entry_num < batch_len; entry_num++) + { + CoglJournalEntry *journal_entry = batch_start + entry_num; + CoglPipeline *pipeline = journal_entry->pipeline; + ClipBounds *clip_bounds = &g_array_index (ctx->journal_clip_bounds, + ClipBounds, entry_num); + int layer_num; + + clip_bounds->x_1 = -G_MAXFLOAT; + clip_bounds->y_1 = -G_MAXFLOAT; + clip_bounds->x_2 = G_MAXFLOAT; + clip_bounds->y_2 = G_MAXFLOAT; + + /* Check the pipeline is usable. We can short-cut here for + entries using the same pipeline as the previous entry */ + if (entry_num == 0 || pipeline != batch_start[entry_num - 1].pipeline) + { + /* If the pipeline has a user program then we can't reliably modify + the texture coordinates */ + if (cogl_pipeline_get_user_program (pipeline)) + return; + + /* If any of the pipeline layers have a texture matrix then we can't + reliably modify the texture coordinates */ + for (layer_num = cogl_pipeline_get_n_layers (pipeline) - 1; + layer_num >= 0; + layer_num--) + if (_cogl_pipeline_layer_has_user_matrix (pipeline, layer_num)) + return; + } + + /* Now we need to verify that each clip entry's matrix is just a + translation of the journal entry's modelview matrix. We can + also work out the bounds of the clip in modelview space using + this translation */ + for (clip_entry = clip_stack; clip_entry; clip_entry = clip_entry->parent) + { + float rect_x1, rect_y1, rect_x2, rect_y2; + CoglClipStackRect *clip_rect; + float tx, ty; + + clip_rect = (CoglClipStackRect *) clip_entry; + + if (!calculate_translation (&clip_rect->matrix, + &journal_entry->model_view, + &tx, &ty)) + return; + + if (clip_rect->x0 < clip_rect->x1) + { + rect_x1 = clip_rect->x0; + rect_x2 = clip_rect->x1; + } + else + { + rect_x1 = clip_rect->x1; + rect_x2 = clip_rect->x0; + } + if (clip_rect->y0 < clip_rect->y1) + { + rect_y1 = clip_rect->y0; + rect_y2 = clip_rect->y1; + } + else + { + rect_y1 = clip_rect->y1; + rect_y2 = clip_rect->y0; + } + + clip_bounds->x_1 = MAX (clip_bounds->x_1, rect_x1 - tx); + clip_bounds->y_1 = MAX (clip_bounds->y_1, rect_y1 - ty); + clip_bounds->x_2 = MIN (clip_bounds->x_2, rect_x2 - tx); + clip_bounds->y_2 = MIN (clip_bounds->y_2, rect_y2 - ty); + } + } + + /* If we make it here then we know we can software clip the entire batch */ + + for (entry_num = 0; entry_num < batch_len; entry_num++) + { + CoglJournalEntry *journal_entry = batch_start + entry_num; + float *verts = &g_array_index (ctx->logged_vertices, float, + journal_entry->array_offset + 1); + ClipBounds *clip_bounds = &g_array_index (ctx->journal_clip_bounds, + ClipBounds, entry_num); + + size_t stride = + GET_JOURNAL_ARRAY_STRIDE_FOR_N_LAYERS (journal_entry->n_layers); + float rx1, ry1, rx2, ry2; + float vx1, vy1, vx2, vy2; + int layer_num; + + /* Remove the clip on the entry */ + _cogl_clip_stack_unref (journal_entry->clip_stack); + journal_entry->clip_stack = NULL; + + vx1 = verts[0]; + vy1 = verts[1]; + vx2 = verts[stride]; + vy2 = verts[stride + 1]; + + if (vx1 < vx2) + { + rx1 = vx1; + rx2 = vx2; + } + else + { + rx1 = vx2; + rx2 = vx1; + } + if (vy1 < vy2) + { + ry1 = vy1; + ry2 = vy2; + } + else + { + ry1 = vy2; + ry2 = vy1; + } + + rx1 = CLAMP (rx1, clip_bounds->x_1, clip_bounds->x_2); + ry1 = CLAMP (ry1, clip_bounds->y_1, clip_bounds->y_2); + rx2 = CLAMP (rx2, clip_bounds->x_1, clip_bounds->x_2); + ry2 = CLAMP (ry2, clip_bounds->y_1, clip_bounds->y_2); + + /* Check if the rectangle intersects the clip at all */ + if (rx1 == rx2 || ry1 == ry2) + /* Will set all of the vertex data to 0 in the hope that this + will create a degenerate rectangle and the GL driver will + be able to clip it quickly */ + memset (verts, 0, sizeof (float) * stride * 2); + else + { + if (vx1 > vx2) + { + float t = rx1; + rx1 = rx2; + rx2 = t; + } + if (vy1 > vy2) + { + float t = ry1; + ry1 = ry2; + ry2 = t; + } + + verts[0] = rx1; + verts[1] = ry1; + verts[stride] = rx2; + verts[stride + 1] = ry2; + + /* Convert the rectangle coordinates to a fraction of the original + rectangle */ + rx1 = (rx1 - vx1) / (vx2 - vx1); + ry1 = (ry1 - vy1) / (vy2 - vy1); + rx2 = (rx2 - vx1) / (vx2 - vx1); + ry2 = (ry2 - vy1) / (vy2 - vy1); + + for (layer_num = 0; layer_num < journal_entry->n_layers; layer_num++) + { + float *t = verts + 2 + 2 * layer_num; + float tx1 = t[0], ty1 = t[1]; + float tx2 = t[stride], ty2 = t[stride + 1]; + t[0] = rx1 * (tx2 - tx1) + tx1; + t[1] = ry1 * (ty2 - ty1) + ty1; + t[stride] = rx2 * (tx2 - tx1) + tx1; + t[stride + 1] = ry2 * (ty2 - ty1) + ty1; + } + } + } + + return; +} + +static void +_cogl_journal_check_software_clip (CoglJournalEntry *batch_start, + int batch_len, + void *data) +{ + CoglJournalFlushState *state = data; + + COGL_STATIC_TIMER (time_check_software_clip, + "Journal Flush", /* parent */ + "flush: check software clip", + "Time spent checking for software clip", + 0 /* no application private data */); + + _COGL_GET_CONTEXT (ctx, NO_RETVAL); + + COGL_TIMER_START (_cogl_uprof_context, + time_check_software_clip); + + check_software_clip_for_batch (batch_start, batch_len, state); + + COGL_TIMER_STOP (_cogl_uprof_context, + time_check_software_clip); +} + static gboolean compare_entry_clip_stacks (CoglJournalEntry *entry0, CoglJournalEntry *entry1) { @@ -812,19 +1148,33 @@ _cogl_journal_flush (void) if (G_UNLIKELY (cogl_debug_flags & COGL_DEBUG_BATCHING)) g_print ("BATCHING: journal len = %d\n", ctx->journal->len); - state.vertex_array = upload_vertices (&g_array_index (ctx->journal, - CoglJournalEntry, 0), - ctx->journal->len, - ctx->journal_needed_vbo_len, - ctx->logged_vertices); state.attributes = ctx->journal_flush_attributes_array; - state.array_offset = 0; framebuffer = _cogl_get_framebuffer (); modelview_stack = _cogl_framebuffer_get_modelview_stack (framebuffer); state.modelview_stack = modelview_stack; state.projection_stack = _cogl_framebuffer_get_projection_stack (framebuffer); + /* We do an initial walk of the journal to analyse the clip stack + batches to see if we can do software clipping. We do this as a + separate walk of the journal because we can modify entries and + this may end up joining together clip stack batches in the next + iteration. */ + batch_and_call ((CoglJournalEntry *)ctx->journal->data, /* first entry */ + ctx->journal->len, /* max number of entries to consider */ + compare_entry_clip_stacks, + _cogl_journal_check_software_clip, /* callback */ + &state); /* data */ + + /* We upload the vertices after the clip stack pass in case it + modifies the entries */ + state.vertex_array = upload_vertices (&g_array_index (ctx->journal, + CoglJournalEntry, 0), + ctx->journal->len, + ctx->journal_needed_vbo_len, + ctx->logged_vertices); + state.array_offset = 0; + /* batch_and_call() batches a list of journal entries according to some * given criteria and calls a callback once for each determined batch. * @@ -975,6 +1325,7 @@ _cogl_journal_log_quad (const float *position, entry = &g_array_index (ctx->journal, CoglJournalEntry, next_entry); entry->n_layers = n_layers; + entry->array_offset = next_vert; source = pipeline;