Tables: Extend outer-most clip limits to match those of host when merging draw calls.

Generally clarify/simplify ClipRect extending/merging code in TableReorderDrawChannelsForMerge().
Amend/fix Sep 23
This commit is contained in:
ocornut 2020-09-18 20:44:50 +02:00
parent 3d573103b6
commit f6800e9d3b

View File

@ -69,18 +69,20 @@
// | - TableSetColumnWidth() - apply resizing width (for mouse resize, often requested by previous frame)
// | - TableUpdateColumnsWeightFromWidth()- recompute columns weights (of stretch columns) from their respective width
// - TableSetupColumn() user submit columns details (optional)
// - TableUpdateLayout() [Internal] automatically called by the FIRST call to TableNextRow() or Table*Header(): lock all widths, columns positions, clipping rectangles
// | TableUpdateDrawChannels() - setup ImDrawList channels
// | TableUpdateBorders() - detect hovering columns for resize, ahead of contents submission
// | TableDrawContextMenu() - draw right-click context menu
//-----------------------------------------------------------------------------
// - TableAutoHeaders() or TableHeader() user submit a headers row (optional)
// | TableSortSpecsClickColumn() - when left-clicked: alter sort order and sort direction
// | TableOpenContextMenu() - when right-clicked: trigger opening of the default context menu
// - TableGetSortSpecs() user queries updated sort specs (optional, generally after submitting headers)
// - TableNextRow() / TableNextCell() user begin into the first row, also automatically called by TableAutoHeaders()
// | TableUpdateLayout() - lock all widths, columns positions, clipping rectangles. called by the FIRST call to TableNextRow()!
// | - TableUpdateDrawChannels() - setup ImDrawList channels
// | - TableUpdateBorders() - detect hovering columns for resize, ahead of contents submission
// | - TableDrawContextMenu() - draw right-click context menu
// | TableEndCell() - close existing cell if not the first time
// | TableBeginCell() - enter into current cell
// - [...] user emit contents
//-----------------------------------------------------------------------------
// - EndTable() user ends the table
// | TableDrawBorders() - draw outer borders, inner vertical borders
// | TableReorderDrawChannelsForMerge() - merge draw channels if clipping isn't required
@ -1375,7 +1377,6 @@ void ImGui::TableReorderDrawChannelsForMerge(ImGuiTable* table)
int merge_group_mask = 0x00;
MergeGroup merge_groups[4];
memset(merge_groups, 0, sizeof(merge_groups));
bool merge_groups_all_fit_within_inner_rect = (table->Flags & ImGuiTableFlags_NoHostExtendY) == 0;
// 1. Scan channels and take note of those which can be merged
for (int column_n = 0; column_n < table->ColumnsCount; column_n++)
@ -1396,7 +1397,8 @@ void ImGui::TableReorderDrawChannelsForMerge(ImGuiTable* table)
if (src_channel->_CmdBuffer.Size != 1)
continue;
// Find out the width of this merge group and check if it will fit in our column.
// Find out the width of this merge group and check if it will fit in our column
// (note that we assume that rendering didn't stray on the left direction. we should need a CursorMinPos to detect it)
if (!(column->Flags & ImGuiTableColumnFlags_NoClipX))
{
float width_contents;
@ -1410,28 +1412,15 @@ void ImGui::TableReorderDrawChannelsForMerge(ImGuiTable* table)
continue;
}
const int merge_group_dst_n = (is_frozen_h && column_n < table->FreezeColumnsCount ? 0 : 2) + (is_frozen_v ? merge_group_sub_n : 1);
const int merge_group_n = (is_frozen_h && column_n < table->FreezeColumnsCount ? 0 : 2) + (is_frozen_v ? merge_group_sub_n : 1);
IM_ASSERT(channel_no < IMGUI_TABLE_MAX_DRAW_CHANNELS);
MergeGroup* merge_group = &merge_groups[merge_group_dst_n];
MergeGroup* merge_group = &merge_groups[merge_group_n];
if (merge_group->ChannelsCount == 0)
merge_group->ClipRect = ImRect(+FLT_MAX, +FLT_MAX, -FLT_MAX, -FLT_MAX);
merge_group->ChannelsMask.SetBit(channel_no);
merge_group->ChannelsCount++;
merge_group->ClipRect.Add(src_channel->_CmdBuffer[0].ClipRect);
merge_group_mask |= (1 << merge_group_dst_n);
// If we end with a single group and hosted by the outer window, we'll attempt to merge our draw command
// with the existing outer window command. But we can only do so if our columns all fit within the expected
// clip rect, otherwise clipping will be incorrect when ScrollX is disabled.
// FIXME-TABLE FIXME-WORKRECT: We are wasting a merge opportunity on tables without scrolling if column don't fit within host clip rect, solely because of the half-padding difference between window->WorkRect and window->InnerClipRect
// 2019/10/22: (1) This is breaking table_2_draw_calls but I cannot seem to repro what it is attempting to
// fix... cf git fce2e8dc "Fixed issue with clipping when outerwindow==innerwindow / support ScrollH without ScrollV."
// 2019/10/22: (2) Clamping code in TableUpdateLayout() seemingly made this not necessary...
#if 0
if (column->MinX < table->InnerClipRect.Min.x || column->MaxX > table->InnerClipRect.Max.x)
merge_groups_all_fit_within_inner_rect = false;
#endif
merge_group_mask |= (1 << merge_group_n);
}
// Invalidate current draw channel
@ -1460,10 +1449,6 @@ void ImGui::TableReorderDrawChannelsForMerge(ImGuiTable* table)
// 2. Rewrite channel list in our preferred order
if (merge_group_mask != 0)
{
// Conceptually we want to test if only 1 bit of merge_group_mask is set, but with no freezing we know it's always going to be group 3.
// We need to test for !is_frozen because any unfitting column will not be part of a merge group, so testing for merge_group_mask isn't enough.
const bool may_extend_clip_rect_to_host_rect = (merge_group_mask == (1 << 3)) && !is_frozen_v && !is_frozen_h;
// Use shared temporary storage so the allocation gets amortized
g.DrawChannelsTempMergeBuffer.resize(splitter->_Count - 1);
ImDrawChannel* dst_tmp = g.DrawChannelsTempMergeBuffer.Data;
@ -1475,16 +1460,28 @@ void ImGui::TableReorderDrawChannelsForMerge(ImGuiTable* table)
if (int merge_channels_count = merge_groups[merge_group_n].ChannelsCount)
{
MergeGroup* merge_group = &merge_groups[merge_group_n];
ImRect merge_clip_rect = merge_groups[merge_group_n].ClipRect;
if (may_extend_clip_rect_to_host_rect)
{
IM_ASSERT(merge_group_n == 3);
//GetOverlayDrawList()->AddRect(table->HostClipRect.Min, table->HostClipRect.Max, IM_COL32(255, 0, 0, 200), 0.0f, ~0, 3.0f);
//GetOverlayDrawList()->AddRect(table->InnerClipRect.Min, table->InnerClipRect.Max, IM_COL32(0, 255, 0, 200), 0.0f, ~0, 1.0f);
//GetOverlayDrawList()->AddRect(merge_clip_rect.Min, merge_clip_rect.Max, IM_COL32(255, 0, 0, 200), 0.0f, ~0, 2.0f);
merge_clip_rect.Add(merge_groups_all_fit_within_inner_rect ? table->HostClipRect : table->InnerClipRect);
//GetOverlayDrawList()->AddRect(merge_clip_rect.Min, merge_clip_rect.Max, IM_COL32(0, 255, 0, 200));
}
ImRect merge_clip_rect = merge_group->ClipRect;
// Extend outer-most clip limits to match those of host, so draw calls can be merged even if
// outer-most columns have some outer padding offsetting them from their parent ClipRect.
// The principal cases this is dealing with are:
// - On a same-window table (not scrolling = single group), all fitting columns ClipRect -> will extend and match host ClipRect -> will merge
// - Columns can use padding and have left-most ClipRect.Min.x and right-most ClipRect.Max.x != from host ClipRect -> will extend and match host ClipRect -> will merge
// FIXME-TABLE FIXME-WORKRECT: We are wasting a merge opportunity on tables without scrolling if column doesn't fit
// within host clip rect, solely because of the half-padding difference between window->WorkRect and window->InnerClipRect.
if ((merge_group_n & 2) == 0 || !is_frozen_h)
merge_clip_rect.Min.x = ImMin(merge_clip_rect.Min.x, table->HostClipRect.Min.x);
if ((merge_group_n & 1) == 0 || !is_frozen_v)
merge_clip_rect.Min.y = ImMin(merge_clip_rect.Min.y, table->HostClipRect.Min.y);
if ((merge_group_n & 2) != 0)
merge_clip_rect.Max.x = ImMax(merge_clip_rect.Max.x, table->HostClipRect.Max.x);
if ((merge_group_n & 1) != 0 && (table->Flags & ImGuiTableFlags_NoHostExtendY) == 0)
merge_clip_rect.Max.y = ImMax(merge_clip_rect.Max.y, table->HostClipRect.Max.y);
#if 0
GetOverlayDrawList()->AddRect(merge_group->ClipRect.Min, merge_group->ClipRect.Max, IM_COL32(255, 0, 0, 200), 0.0f, ~0, 1.0f);
GetOverlayDrawList()->AddLine(merge_group->ClipRect.Min, merge_clip_rect.Min, IM_COL32(255, 100, 0, 200));
GetOverlayDrawList()->AddLine(merge_group->ClipRect.Max, merge_clip_rect.Max, IM_COL32(255, 100, 0, 200));
#endif
remaining_count -= merge_group->ChannelsCount;
for (int n = 0; n < IM_ARRAYSIZE(remaining_mask.Storage); n++)
remaining_mask.Storage[n] &= ~merge_group->ChannelsMask.Storage[n];