From 3a6c9907cd182795f82c67df5d77e88bcfe9563c Mon Sep 17 00:00:00 2001 From: omar Date: Tue, 7 Jul 2020 13:24:10 +0200 Subject: [PATCH] Texture-based thick lines: Minor tweaks and rename toward merging in master. Changes to allow changing AA_SIZE (disable texture path). --- docs/CHANGELOG.txt | 9 +++++ imgui.cpp | 6 ++-- imgui.h | 28 +++++++-------- imgui_demo.cpp | 2 +- imgui_draw.cpp | 85 +++++++++++++++++++--------------------------- imgui_internal.h | 3 +- 6 files changed, 63 insertions(+), 70 deletions(-) diff --git a/docs/CHANGELOG.txt b/docs/CHANGELOG.txt index c62a140d..8043bf47 100644 --- a/docs/CHANGELOG.txt +++ b/docs/CHANGELOG.txt @@ -35,6 +35,15 @@ HOW TO UPDATE? VERSION 1.78 WIP (In Progress) ----------------------------------------------------------------------- +Other Changes: + +- ImDrawList: Thick anti-aliased strokes (> 1.0f) with integer thickness now use a texture-based + path, reducing the amount of vertices/indices and CPU/GPU usage. (#3245) [@Shironekoben] + - This change will facilitate the wider use of thick borders in future style changes. + - Requires an extra bit of texture space (~64x64 by default), relies on GPU bilinear filtering. + - Clear io.AntiAliasedLinesUseTex = false; to disable rendering using this method. + - Clear ImFontAtlasFlags_NoBakedLines in ImFontAtlas::Flags to disable baking data in texture. + ----------------------------------------------------------------------- VERSION 1.77 (Released 2020-06-29) diff --git a/imgui.cpp b/imgui.cpp index b9c300fa..37e611ad 100644 --- a/imgui.cpp +++ b/imgui.cpp @@ -935,7 +935,7 @@ ImGuiStyle::ImGuiStyle() DisplaySafeAreaPadding = ImVec2(3,3); // If you cannot see the edge of your screen (e.g. on a TV) increase the safe area padding. Covers popups/tooltips as well regular windows. MouseCursorScale = 1.0f; // Scale software rendered mouse cursor (when io.MouseDrawCursor is enabled). May be removed later. AntiAliasedLines = true; // Enable anti-aliased lines/borders. Disable if you are really tight on CPU/GPU. - AntiAliasedLinesUseTex = true; // Enable anti-aliased lines/borders using textures where possible. Requires back-end to render with bilinear filtering. + AntiAliasedLinesUseTex = true; // Enable anti-aliased lines/borders using textures where possible. Require back-end to render with bilinear filtering. AntiAliasedFill = true; // Enable anti-aliased filled shapes (rounded rectangles, circles, etc.). CurveTessellationTol = 1.25f; // Tessellation tolerance when using PathBezierCurveTo() without a specific number of segments. Decrease for highly tessellated curves (higher quality, more polygons), increase to reduce quality. CircleSegmentMaxError = 1.60f; // Maximum error (in pixels) allowed when using AddCircle()/AddCircleFilled() or drawing rounded corner rectangles with no explicit segment count specified. Decrease for higher quality but more geometry. @@ -3689,7 +3689,7 @@ void ImGui::NewFrame() g.DrawListSharedData.InitialFlags = ImDrawListFlags_None; if (g.Style.AntiAliasedLines) g.DrawListSharedData.InitialFlags |= ImDrawListFlags_AntiAliasedLines; - if (g.Style.AntiAliasedLinesUseTex && !(g.Font->ContainerAtlas->Flags & ImFontAtlasFlags_NoAntiAliasedLines)) + if (g.Style.AntiAliasedLinesUseTex && !(g.Font->ContainerAtlas->Flags & ImFontAtlasFlags_NoBakedLines)) g.DrawListSharedData.InitialFlags |= ImDrawListFlags_AntiAliasedLinesUseTex; if (g.Style.AntiAliasedFill) g.DrawListSharedData.InitialFlags |= ImDrawListFlags_AntiAliasedFill; @@ -6161,7 +6161,7 @@ void ImGui::SetCurrentFont(ImFont* font) ImFontAtlas* atlas = g.Font->ContainerAtlas; g.DrawListSharedData.TexUvWhitePixel = atlas->TexUvWhitePixel; - g.DrawListSharedData.TexUvAALines = atlas->TexUvAALines; + g.DrawListSharedData.TexUvLines = atlas->TexUvLines; g.DrawListSharedData.Font = g.Font; g.DrawListSharedData.FontSize = g.FontSize; } diff --git a/imgui.h b/imgui.h index 5e86bae5..6f4dec52 100644 --- a/imgui.h +++ b/imgui.h @@ -60,7 +60,7 @@ Index of this file: // Version // (Integer encoded as XYYZZ for use in #if preprocessor conditionals. Work in progress versions typically starts at XYY99 then bounce up to XYY00, XYY01 etc. when release tagging happens) #define IMGUI_VERSION "1.78 WIP" -#define IMGUI_VERSION_NUM 17702 +#define IMGUI_VERSION_NUM 17703 #define IMGUI_CHECKVERSION() ImGui::DebugCheckVersionAndDataLayout(IMGUI_VERSION, sizeof(ImGuiIO), sizeof(ImGuiStyle), sizeof(ImVec2), sizeof(ImVec4), sizeof(ImDrawVert), sizeof(ImDrawIdx)) // Define attributes of all API symbols declarations (e.g. for DLL under Windows) @@ -1438,9 +1438,9 @@ struct ImGuiStyle ImVec2 DisplayWindowPadding; // Window position are clamped to be visible within the display area by at least this amount. Only applies to regular windows. ImVec2 DisplaySafeAreaPadding; // If you cannot see the edges of your screen (e.g. on a TV) increase the safe area padding. Apply to popups/tooltips as well regular windows. NB: Prefer configuring your TV sets correctly! float MouseCursorScale; // Scale software rendered mouse cursor (when io.MouseDrawCursor is enabled). May be removed later. - bool AntiAliasedLines; // Enable anti-aliased lines/borders. Disable if you are really tight on CPU/GPU. - bool AntiAliasedLinesUseTex; // Enable anti-aliased lines/borders using textures where possible. Requires back-end to render with bilinear filtering. - bool AntiAliasedFill; // Enable anti-aliased edges around filled shapes (rounded rectangles, circles, etc.). Disable if you are really tight on CPU/GPU. + bool AntiAliasedLines; // Enable anti-aliased lines/borders. Disable if you are really tight on CPU/GPU. Latched at the beginning of the frame (copied to ImDrawList). + bool AntiAliasedLinesUseTex; // Enable anti-aliased lines/borders using textures where possible. Require back-end to render with bilinear filtering. Latched at the beginning of the frame (copied to ImDrawList). + bool AntiAliasedFill; // Enable anti-aliased edges around filled shapes (rounded rectangles, circles, etc.). Disable if you are really tight on CPU/GPU. Latched at the beginning of the frame (copied to ImDrawList). float CurveTessellationTol; // Tessellation tolerance when using PathBezierCurveTo() without a specific number of segments. Decrease for highly tessellated curves (higher quality, more polygons), increase to reduce quality. float CircleSegmentMaxError; // Maximum error (in pixels) allowed when using AddCircle()/AddCircleFilled() or drawing rounded corner rectangles with no explicit segment count specified. Decrease for higher quality but more geometry. ImVec4 Colors[ImGuiCol_COUNT]; @@ -1897,9 +1897,9 @@ struct ImColor // Hold a series of drawing commands. The user provides a renderer for ImDrawData which essentially contains an array of ImDrawList. //----------------------------------------------------------------------------- -// The maximum line width to bake anti-aliased textures for. Build atlas with ImFontAtlasFlags_NoAALines to disable baking. -#ifndef IM_DRAWLIST_TEX_AA_LINES_WIDTH_MAX -#define IM_DRAWLIST_TEX_AA_LINES_WIDTH_MAX (63) +// The maximum line width to bake anti-aliased textures for. Build atlas with ImFontAtlasFlags_NoBakedLines to disable baking. +#ifndef IM_DRAWLIST_TEX_LINES_WIDTH_MAX +#define IM_DRAWLIST_TEX_LINES_WIDTH_MAX (63) #endif // ImDrawCallback: Draw callbacks for advanced uses [configurable type: override in imconfig.h] @@ -1998,14 +1998,14 @@ enum ImDrawCornerFlags_ ImDrawCornerFlags_All = 0xF // In your function calls you may use ~0 (= all bits sets) instead of ImDrawCornerFlags_All, as a convenience }; -#define IMGUI_HAS_TEXLINES 1 - +// Flags for ImDrawList. Those are set automatically by ImGui:: functions from ImGuiIO settings, and generally not manipulated directly. +// It is however possible to temporarily alter flags between calls to ImDrawList:: functions. enum ImDrawListFlags_ { ImDrawListFlags_None = 0, ImDrawListFlags_AntiAliasedLines = 1 << 0, // Enable anti-aliased lines/borders (*2 the number of triangles for 1.0f wide line or lines thin enough to be drawn using textures, otherwise *3 the number of triangles) - ImDrawListFlags_AntiAliasedFill = 1 << 1, // Enable anti-aliased edge around filled shapes (rounded rectangles, circles). - ImDrawListFlags_AntiAliasedLinesUseTex = 1 << 2, // Should anti-aliased lines be drawn using textures where possible? + ImDrawListFlags_AntiAliasedLinesUseTex = 1 << 1, // Enable anti-aliased lines/borders using textures when possible. Require back-end to render with bilinear filtering. + ImDrawListFlags_AntiAliasedFill = 1 << 2, // Enable anti-aliased edge around filled shapes (rounded rectangles, circles). ImDrawListFlags_AllowVtxOffset = 1 << 3 // Can emit 'VtxOffset > 0' to allow large meshes. Set when 'ImGuiBackendFlags_RendererHasVtxOffset' is enabled. }; @@ -2226,7 +2226,7 @@ enum ImFontAtlasFlags_ ImFontAtlasFlags_None = 0, ImFontAtlasFlags_NoPowerOfTwoHeight = 1 << 0, // Don't round the height to next power of two ImFontAtlasFlags_NoMouseCursors = 1 << 1, // Don't build software mouse cursors into the atlas (save a little texture memory) - ImFontAtlasFlags_NoAntiAliasedLines = 1 << 2 // Don't build anti-aliased line textures into the atlas (save a little texture memory). They will be rendered using polygons (a little bit more expensive) + ImFontAtlasFlags_NoBakedLines = 1 << 2 // Don't build thick line textures into the atlas (save a little texture memory). The AntiAliasedLinesUseTex features uses them, otherwise they will be rendered using polygons (more expensive for CPU/GPU). }; // Load and rasterize multiple TTF/OTF fonts into a same texture. The font atlas will build a single texture holding: @@ -2327,11 +2327,11 @@ struct ImFontAtlas ImVector Fonts; // Hold all the fonts returned by AddFont*. Fonts[0] is the default font upon calling ImGui::NewFrame(), use ImGui::PushFont()/PopFont() to change the current font. ImVector CustomRects; // Rectangles for packing custom texture data into the atlas. ImVector ConfigData; // Configuration data - ImVec4 TexUvAALines[IM_DRAWLIST_TEX_AA_LINES_WIDTH_MAX + 1]; // UVs for anti-aliased line textures + ImVec4 TexUvLines[IM_DRAWLIST_TEX_LINES_WIDTH_MAX + 1]; // UVs for baked anti-aliased lines // [Internal] Packing data int PackIdMouseCursors; // Custom texture rectangle ID for white pixel and mouse cursors - int PackIdAALines; // Custom texture rectangle ID for anti-aliased lines + int PackIdLines; // Custom texture rectangle ID for baked anti-aliased lines #ifndef IMGUI_DISABLE_OBSOLETE_FUNCTIONS typedef ImFontAtlasCustomRect CustomRect; // OBSOLETED in 1.72+ diff --git a/imgui_demo.cpp b/imgui_demo.cpp index 8b5d57d4..d66bf014 100644 --- a/imgui_demo.cpp +++ b/imgui_demo.cpp @@ -3832,7 +3832,7 @@ void ImGui::ShowStyleEditor(ImGuiStyle* ref) ImGui::Checkbox("Anti-aliased lines", &style.AntiAliasedLines); ImGui::SameLine(); HelpMarker("When disabling anti-aliasing lines, you'll probably want to disable borders in your style as well."); ImGui::Checkbox("Anti-aliased lines use texture", &style.AntiAliasedLinesUseTex); - ImGui::SameLine(); HelpMarker("Faster lines using texture data. Requires texture to use bilinear sampling (not nearest)."); + ImGui::SameLine(); HelpMarker("Faster lines using texture data. Require back-end to render with bilinear filtering (not point/nearest filtering)."); ImGui::Checkbox("Anti-aliased fill", &style.AntiAliasedFill); ImGui::PushItemWidth(100); ImGui::DragFloat("Curve Tessellation Tolerance", &style.CurveTessellationTol, 0.02f, 0.10f, 10.0f, "%.2f"); diff --git a/imgui_draw.cpp b/imgui_draw.cpp index 15a6c6f2..942c2d90 100644 --- a/imgui_draw.cpp +++ b/imgui_draw.cpp @@ -358,7 +358,7 @@ ImDrawListSharedData::ImDrawListSharedData() ArcFastVtx[i] = ImVec2(ImCos(a), ImSin(a)); } memset(CircleSegmentCounts, 0, sizeof(CircleSegmentCounts)); // This will be set by SetCircleSegmentMaxError() - TexUvAALines = NULL; + TexUvLines = NULL; } void ImDrawListSharedData::SetCircleSegmentMaxError(float max_error) @@ -681,11 +681,13 @@ void ImDrawList::AddPolyline(const ImVec2* points, const int points_count, ImU32 const int integer_thickness = (int)thickness; const float fractional_thickness = thickness - integer_thickness; - // Do we want to draw this line using a texture? (for now, only draw integer-width lines using textures to avoid issues with the way scaling occurs) - const bool use_texture = (Flags & ImDrawListFlags_AntiAliasedLinesUseTex) && (integer_thickness < IM_DRAWLIST_TEX_AA_LINES_WIDTH_MAX) && (fractional_thickness >= -0.00001f) && (fractional_thickness <= 0.00001f); + // Do we want to draw this line using a texture? + // - For now, only draw integer-width lines using textures to avoid issues with the way scaling occurs, could be improved. + // - If AA_SIZE is not 1.0f we cannot use the texture path. + const bool use_texture = (Flags & ImDrawListFlags_AntiAliasedLinesUseTex) && (integer_thickness < IM_DRAWLIST_TEX_LINES_WIDTH_MAX) && (fractional_thickness <= 0.00001f); - // We should never hit this, because NewFrame() doesn't set ImDrawListFlags_AntiAliasedLinesUseTexData unless ImFontAtlasFlags_NoAALines is off - IM_ASSERT_PARANOID((!use_texture) || (!(_Data->Font->ContainerAtlas->Flags & ImFontAtlasFlags_NoAALines))); + // We should never hit this, because NewFrame() doesn't set ImDrawListFlags_AntiAliasedLinesUseTex unless ImFontAtlasFlags_NoBakedLines is off + IM_ASSERT_PARANOID(!use_texture || !(_Data->Font->ContainerAtlas->Flags & ImFontAtlasFlags_NoBakedLines)); const int idx_count = use_texture ? (count * 6) : (thick_line ? count * 18 : count * 12); const int vtx_count = use_texture ? (points_count * 2) : (thick_line ? points_count * 4 : points_count * 3); @@ -693,7 +695,7 @@ void ImDrawList::AddPolyline(const ImVec2* points, const int points_count, ImU32 // Temporary buffer // The first items are normals at each line point, then after that there are either 2 or 4 temp points for each line point - ImVec2* temp_normals = (ImVec2*)alloca(points_count * ((thick_line && !use_texture) ? 5 : 3) * sizeof(ImVec2)); //-V630 + ImVec2* temp_normals = (ImVec2*)alloca(points_count * ((use_texture || !thick_line) ? 3 : 5) * sizeof(ImVec2)); //-V630 ImVec2* temp_points = temp_normals + points_count; // Calculate normals (tangents) for each line segment @@ -717,7 +719,7 @@ void ImDrawList::AddPolyline(const ImVec2* points, const int points_count, ImU32 // The width of the geometry we need to draw - this is essentially pixels for the line itself, plus one pixel for AA // We don't use AA_SIZE here because the +1 is tied to the generated texture and so alternate values won't work without changes to that code - const float half_draw_size = use_texture ? ((thickness * 0.5f) + 1) : 1.0f; + const float half_draw_size = use_texture ? ((thickness * 0.5f) + 1) : AA_SIZE; // If line is not closed, the first and last points need to be generated differently as there are no normals to blend if (!closed) @@ -775,10 +777,10 @@ void ImDrawList::AddPolyline(const ImVec2* points, const int points_count, ImU32 if (use_texture) { // If we're using textures we only need to emit the left/right edge vertices - ImVec4 tex_uvs = _Data->TexUvAALines[integer_thickness]; + ImVec4 tex_uvs = _Data->TexUvLines[integer_thickness]; if (fractional_thickness != 0.0f) { - const ImVec4 tex_uvs_1 = _Data->TexUvAALines[integer_thickness + 1]; + const ImVec4 tex_uvs_1 = _Data->TexUvLines[integer_thickness + 1]; tex_uvs.x = tex_uvs.x + (tex_uvs_1.x - tex_uvs.x) * fractional_thickness; // inlined ImLerp() tex_uvs.y = tex_uvs.y + (tex_uvs_1.y - tex_uvs.y) * fractional_thickness; tex_uvs.z = tex_uvs.z + (tex_uvs_1.z - tex_uvs.z) * fractional_thickness; @@ -1719,7 +1721,7 @@ ImFontAtlas::ImFontAtlas() TexWidth = TexHeight = 0; TexUvScale = ImVec2(0.0f, 0.0f); TexUvWhitePixel = ImVec2(0.0f, 0.0f); - PackIdMouseCursors = PackIdAALines = -1; + PackIdMouseCursors = PackIdLines = -1; } ImFontAtlas::~ImFontAtlas() @@ -1747,7 +1749,7 @@ void ImFontAtlas::ClearInputData() } ConfigData.clear(); CustomRects.clear(); - PackIdMouseCursors = PackIdAALines = -1; + PackIdMouseCursors = PackIdLines = -1; } void ImFontAtlas::ClearTexData() @@ -2387,27 +2389,15 @@ static void ImFontAtlasBuildRenderDefaultTexData(ImFontAtlas* atlas) atlas->TexUvWhitePixel = ImVec2((r->X + 0.5f) * atlas->TexUvScale.x, (r->Y + 0.5f) * atlas->TexUvScale.y); } -static void ImFontAtlasBuildRegisterAALineCustomRects(ImFontAtlas* atlas) +static void ImFontAtlasBuildRenderLinesTexData(ImFontAtlas* atlas) { - if (atlas->Flags & ImFontAtlasFlags_NoAntiAliasedLines) + if (atlas->Flags & ImFontAtlasFlags_NoBakedLines) return; - // The +2 here is to give space for the end caps, whilst height +1 is to accommodate the fact we have a zero-width row - atlas->PackIdAALines = atlas->AddCustomRectRegular(IM_DRAWLIST_TEX_AA_LINES_WIDTH_MAX + 2, IM_DRAWLIST_TEX_AA_LINES_WIDTH_MAX + 1); -} - -static void ImFontAtlasBuildRenderAALinesTexData(ImFontAtlas* atlas) -{ - IM_ASSERT(atlas->TexPixelsAlpha8 != NULL); - if (atlas->Flags & ImFontAtlasFlags_NoAntiAliasedLines) - return; - - ImFontAtlasCustomRect* r = atlas->GetCustomRectByIndex(atlas->PackIdAALines); - IM_ASSERT(r->IsPacked()); - // This generates a triangular shape in the texture, with the various line widths stacked on top of each other to allow interpolation between them - const int w = atlas->TexWidth; - for (unsigned int n = 0; n < IM_DRAWLIST_TEX_AA_LINES_WIDTH_MAX + 1; n++) // +1 because of the zero-width row + ImFontAtlasCustomRect* r = atlas->GetCustomRectByIndex(atlas->PackIdLines); + IM_ASSERT(r->IsPacked()); + for (unsigned int n = 0; n < IM_DRAWLIST_TEX_LINES_WIDTH_MAX + 1; n++) // +1 because of the zero-width row { // Each line consists of at least two empty pixels at the ends, with a line of solid pixels in the middle unsigned int y = n; @@ -2415,30 +2405,18 @@ static void ImFontAtlasBuildRenderAALinesTexData(ImFontAtlas* atlas) unsigned int pad_left = (r->Width - line_width) / 2; unsigned int pad_right = r->Width - (pad_left + line_width); - // Make sure we're inside the texture bounds before we start writing pixels - IM_ASSERT_PARANOID(pad_left + line_width + pad_right == r.Width); - IM_ASSERT_PARANOID(y < r.Height); - // Write each slice - unsigned char* write_ptr = &atlas->TexPixelsAlpha8[r->X + ((r->Y + y) * w)]; - for (unsigned int x = 0; x < pad_left; x++) - *(write_ptr++) = 0; - for (unsigned int x = 0; x < line_width; x++) - *(write_ptr++) = 0xFF; - for (unsigned int x = 0; x < pad_right; x++) - *(write_ptr++) = 0; + IM_ASSERT(pad_left + line_width + pad_right == r->Width && y < r->Height); // Make sure we're inside the texture bounds before we start writing pixels + unsigned char* write_ptr = &atlas->TexPixelsAlpha8[r->X + ((r->Y + y) * atlas->TexWidth)]; + memset(write_ptr, 0x00, pad_left); + memset(write_ptr + pad_left, 0xFF, line_width); + memset(write_ptr + pad_left + line_width, 0x00, pad_right); // Calculate UVs for this line - ImFontAtlasCustomRect line_rect = *r; - line_rect.X += (unsigned short)(pad_left - 1); - line_rect.Y += (unsigned short)y; - line_rect.Width = (unsigned short)(line_width + 2); - line_rect.Height = 1; - - ImVec2 uv0, uv1; - atlas->CalcCustomRectUV(&line_rect, &uv0, &uv1); + ImVec2 uv0 = ImVec2((float)(r->X + pad_left - 1), (float)(r->Y + y)) * atlas->TexUvScale; + ImVec2 uv1 = ImVec2((float)(r->X + pad_left + line_width + 1), (float)(r->Y + y + 1)) * atlas->TexUvScale; float half_v = (uv0.y + uv1.y) * 0.5f; // Calculate a constant V in the middle of the row to avoid sampling artifacts - atlas->TexUvAALines[n] = ImVec4(uv0.x, half_v, uv1.x, half_v); + atlas->TexUvLines[n] = ImVec4(uv0.x, half_v, uv1.x, half_v); } } @@ -2454,15 +2432,22 @@ void ImFontAtlasBuildInit(ImFontAtlas* atlas) atlas->PackIdMouseCursors = atlas->AddCustomRectRegular(2, 2); } - ImFontAtlasBuildRegisterAALineCustomRects(atlas); + // Register texture region for thick lines + // The +2 here is to give space for the end caps, whilst height +1 is to accommodate the fact we have a zero-width row + if (atlas->PackIdLines < 0) + { + if (!(atlas->Flags & ImFontAtlasFlags_NoBakedLines)) + atlas->PackIdLines = atlas->AddCustomRectRegular(IM_DRAWLIST_TEX_LINES_WIDTH_MAX + 2, IM_DRAWLIST_TEX_LINES_WIDTH_MAX + 1); + } } // This is called/shared by both the stb_truetype and the FreeType builder. void ImFontAtlasBuildFinish(ImFontAtlas* atlas) { // Render into our custom data blocks + IM_ASSERT(atlas->TexPixelsAlpha8 != NULL); ImFontAtlasBuildRenderDefaultTexData(atlas); - ImFontAtlasBuildRenderAALinesTexData(atlas); + ImFontAtlasBuildRenderLinesTexData(atlas); // Register custom rectangle glyphs for (int i = 0; i < atlas->CustomRects.Size; i++) diff --git a/imgui_internal.h b/imgui_internal.h index 629ddc32..a6245d1a 100644 --- a/imgui_internal.h +++ b/imgui_internal.h @@ -544,8 +544,7 @@ struct IMGUI_API ImDrawListSharedData // [Internal] Lookup tables ImVec2 ArcFastVtx[12 * IM_DRAWLIST_ARCFAST_TESSELLATION_MULTIPLIER]; // FIXME: Bake rounded corners fill/borders in atlas ImU8 CircleSegmentCounts[64]; // Precomputed segment count for given radius (array index + 1) before we calculate it dynamically (to avoid calculation overhead) - - const ImVec4* TexUvAALines; // UV of anti-aliased lines in the atlas + const ImVec4* TexUvLines; // UV of anti-aliased lines in the atlas ImDrawListSharedData(); void SetCircleSegmentMaxError(float max_error);