From 7277ab6530032bdb318acc05cc87c8091576ca47 Mon Sep 17 00:00:00 2001 From: ocornut Date: Fri, 13 Mar 2020 11:49:52 +0100 Subject: [PATCH] Tables: Comments, renamed merge_set_xxx to merge_group_xxx. Removed unused array and incorrect assert, replaced with earlier correct assert. (3058) --- imgui_tables.cpp | 78 +++++++++++++++++++++++++----------------------- 1 file changed, 40 insertions(+), 38 deletions(-) diff --git a/imgui_tables.cpp b/imgui_tables.cpp index d380acc98..508acbb44 100644 --- a/imgui_tables.cpp +++ b/imgui_tables.cpp @@ -445,9 +445,9 @@ void ImGui::TableBeginUpdateColumns(ImGuiTable* table) void ImGui::TableUpdateDrawChannels(ImGuiTable* table) { // Allocate draw channels. - // - We allocate them following the storage order instead of the display order so reordering won't needlessly increase overall dormant memory cost + // - We allocate them following the storage order instead of the display order so reordering columns won't needlessly increase overall dormant memory cost. // - We isolate headers draw commands in their own channels instead of just altering clip rects. This is in order to facilitate merging of draw commands. - // - After crossing FreezeRowsCount, all columns see their current draw channel increased. + // - After crossing FreezeRowsCount, all columns see their current draw channel changed to a second set of draw channels. // - We only use the dummy draw channel so we can push a null clipping rectangle into it without affecting other channels, while simplifying per-row/per-cell overhead. It will be empty and discarded when merged. // Draw channel allocation (before merging): // - NoClip --> 1+1 channels: background + foreground (same clip rect == 1 draw call) @@ -1232,13 +1232,13 @@ void ImGui::TableSetColumnWidth(ImGuiTable* table, ImGuiTableColumn* column_0, f // // Each column itself can use 1 channel (row freeze disabled) or 2 channels (row freeze enabled). // When the contents of a column didn't stray off its limit, we move its channels into the corresponding group -// based on its position (within frozen rows/columns set or not). +// based on its position (within frozen rows/columns groups or not). // At the end of the operation our 1-4 groups will each have a ImDrawCmd using the same ClipRect, and they will be merged by the DrawSplitter.Merge() call. // // Column channels will not be merged into one of the 1-4 groups in the following cases: // - The contents stray off its clipping rectangle (we only compare the MaxX value, not the MinX value). -// Direct ImDrawList calls won't be noticed so if you use them make sure the ImGui:: bounds matches, by e.g. calling SetCursorScreenPos(). -// - The channel uses more than one draw command itself (we drop all our merging stuff here.. we could do better but it's going to be rare) +// Direct ImDrawList calls won't be taken into account by default, if you use them make sure the ImGui:: bounds matches, by e.g. calling SetCursorScreenPos(). +// - The channel uses more than one draw command itself. We drop all our merging stuff here.. we could do better but it's going to be rare. // // This function is particularly tricky to understand.. take a breath. void ImGui::TableDrawMergeChannels(ImGuiTable* table) @@ -1248,15 +1248,16 @@ void ImGui::TableDrawMergeChannels(ImGuiTable* table) const bool is_frozen_v = (table->FreezeRowsCount > 0); const bool is_frozen_h = (table->FreezeColumnsCount > 0); - int merge_set_mask = 0; - int merge_set_channels_count[4] = { 0 }; - ImU64 merge_set_channels_mask[4] = { 0 }; - ImRect merge_set_clip_rect[4]; - for (int n = 0; n < IM_ARRAYSIZE(merge_set_clip_rect); n++) - merge_set_clip_rect[n] = ImVec4(+FLT_MAX, +FLT_MAX, -FLT_MAX, -FLT_MAX); - bool merge_set_all_fit_within_inner_rect = (table->Flags & ImGuiTableFlags_NoHostExtendY) == 0; + // Track which groups (1-4) we are going to attempt to merge, and which channels goes into each group. + int merge_group_mask = 0x00; + int merge_group_channels_count[4] = { 0 }; + ImU64 merge_group_channels_mask[4] = { 0 }; + ImRect merge_group_clip_rect[4]; + for (int n = 0; n < IM_ARRAYSIZE(merge_group_clip_rect); n++) + merge_group_clip_rect[n] = ImVec4(+FLT_MAX, +FLT_MAX, -FLT_MAX, -FLT_MAX); + bool merge_groups_all_fit_within_inner_rect = (table->Flags & ImGuiTableFlags_NoHostExtendY) == 0; - // 1. Scan channels and take note of those who can be merged + // 1. Scan channels and take note of those which can be merged for (int order_n = 0; order_n < table->ColumnsCount; order_n++) { if (!(table->ActiveMaskByDisplayOrder & ((ImU64)1 << order_n))) @@ -1264,37 +1265,37 @@ void ImGui::TableDrawMergeChannels(ImGuiTable* table) const int column_n = table->DisplayOrder[order_n]; ImGuiTableColumn* column = &table->Columns[column_n]; - const int merge_set_sub_count = is_frozen_v ? 2 : 1; - for (int merge_set_sub_n = 0; merge_set_sub_n < merge_set_sub_count; merge_set_sub_n++) + const int merge_group_sub_count = is_frozen_v ? 2 : 1; + for (int merge_group_sub_n = 0; merge_group_sub_n < merge_group_sub_count; merge_group_sub_n++) { - const int channel_no = (merge_set_sub_n == 0) ? column->DrawChannelRowsBeforeFreeze : column->DrawChannelRowsAfterFreeze; + const int channel_no = (merge_group_sub_n == 0) ? column->DrawChannelRowsBeforeFreeze : column->DrawChannelRowsAfterFreeze; - // Don't attempt to merge if there are multiple calls within the column + // Don't attempt to merge if there are multiple draw calls within the column ImDrawChannel* src_channel = &splitter->_Channels[channel_no]; if (src_channel->_CmdBuffer.Size > 0 && src_channel->_CmdBuffer.back().ElemCount == 0) src_channel->_CmdBuffer.pop_back(); if (src_channel->_CmdBuffer.Size != 1) continue; - // Find out the width of this merge set 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. float width_contents; - if (merge_set_sub_count == 1) // No row freeze (same as testing !is_frozen_v) + if (merge_group_sub_count == 1) // No row freeze (same as testing !is_frozen_v) width_contents = ImMax(column->ContentWidthRowsUnfrozen, column->ContentWidthHeadersUsed); - else if (merge_set_sub_n == 0) // Row freeze: use width before freeze + else if (merge_group_sub_n == 0) // Row freeze: use width before freeze width_contents = ImMax(column->ContentWidthRowsFrozen, column->ContentWidthHeadersUsed); - else // Row freeze: use width after freeze + else // Row freeze: use width after freeze width_contents = column->ContentWidthRowsUnfrozen; if (width_contents > column->WidthGiven && !(column->Flags & ImGuiTableColumnFlags_NoClipX)) continue; - const int dst_merge_set_n = (is_frozen_h && column_n < table->FreezeColumnsCount ? 0 : 2) + (is_frozen_v ? merge_set_sub_n : 1); - IM_ASSERT(merge_set_channels_count[dst_merge_set_n] < (int)sizeof(merge_set_channels_mask[dst_merge_set_n]) * 8); - merge_set_mask |= (1 << dst_merge_set_n); - merge_set_channels_mask[dst_merge_set_n] |= (ImU64)1 << channel_no; - merge_set_channels_count[dst_merge_set_n]++; - merge_set_clip_rect[dst_merge_set_n].Add(src_channel->_CmdBuffer[0].ClipRect); + const int dst_merge_group_idx = (is_frozen_h && column_n < table->FreezeColumnsCount ? 0 : 2) + (is_frozen_v ? merge_group_sub_n : 1); + IM_ASSERT(channel_no < 64); + merge_group_mask |= (1 << dst_merge_group_idx); + merge_group_channels_mask[dst_merge_group_idx] |= (ImU64)1 << channel_no; + merge_group_channels_count[dst_merge_group_idx]++; + merge_group_clip_rect[dst_merge_group_idx].Add(src_channel->_CmdBuffer[0].ClipRect); - // If we end with a single set and hosted by the outer window, we'll attempt to merge our draw command with + // 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 @@ -1304,7 +1305,7 @@ void ImGui::TableDrawMergeChannels(ImGuiTable* table) // 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_set_all_fit_within_inner_rect = false; + merge_groups_all_fit_within_inner_rect = false; #endif } @@ -1312,25 +1313,26 @@ void ImGui::TableDrawMergeChannels(ImGuiTable* table) column->DrawChannelCurrent = -1; } + // 2. Rewrite channel list in our preferred order - if (merge_set_mask != 0) + if (merge_group_mask != 0) { // Use shared temporary storage so the allocation gets amortized g.DrawChannelsTempMergeBuffer.resize(splitter->_Count - 1); ImDrawChannel* dst_tmp = g.DrawChannelsTempMergeBuffer.Data; - ImU64 remaining_mask = ((splitter->_Count < 64) ? ((ImU64)1 << splitter->_Count) - 1 : ~(ImU64)0) & ~1; - const bool may_extend_clip_rect_to_host_rect = ImIsPowerOfTwo(merge_set_mask); - for (int merge_set_n = 0; merge_set_n < 4; merge_set_n++) - if (merge_set_channels_count[merge_set_n]) + ImU64 remaining_mask = (splitter->_Count < 64) ? ((ImU64)1 << splitter->_Count) - 1 : ~(ImU64)0; + remaining_mask &= (ImU64)~1; // Background channel 0 not part of the merge (see channel allocation in TableUpdateDrawChannels) + const bool may_extend_clip_rect_to_host_rect = ImIsPowerOfTwo(merge_group_mask); + for (int merge_group_n = 0; merge_group_n < 4; merge_group_n++) + if (ImU64 merge_channels_mask = merge_group_channels_mask[merge_group_n]) { - ImU64 merge_channels_mask = merge_set_channels_mask[merge_set_n]; - ImRect merge_clip_rect = merge_set_clip_rect[merge_set_n]; + ImRect merge_clip_rect = merge_group_clip_rect[merge_group_n]; if (may_extend_clip_rect_to_host_rect) { //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_set_all_fit_within_inner_rect ? table->HostClipRect : table->InnerClipRect); + 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)); } remaining_mask &= ~merge_channels_mask; @@ -1348,7 +1350,7 @@ void ImGui::TableDrawMergeChannels(ImGuiTable* table) } } - // Append channels that we didn't reorder at the end of the list + // Append unmergeable channels that we didn't reorder at the end of the list for (int n = 0; n < splitter->_Count && remaining_mask != 0; n++) { const ImU64 n_mask = (ImU64)1 << n;