From 37174c85e270672526baf526f725e915029b0d77 Mon Sep 17 00:00:00 2001 From: omar Date: Thu, 9 May 2019 19:05:36 +0200 Subject: [PATCH] Internal: Scrollbar: Extracted scrollbar code for other uses (eg. table v2 scrolling without using a child window). --- imgui_internal.h | 5 +- imgui_widgets.cpp | 207 ++++++++++++++++++++++++---------------------- 2 files changed, 111 insertions(+), 101 deletions(-) diff --git a/imgui_internal.h b/imgui_internal.h index b8bd9a6c1..fd579a377 100644 --- a/imgui_internal.h +++ b/imgui_internal.h @@ -956,7 +956,7 @@ struct ImGuiContext bool DragCurrentAccumDirty; float DragCurrentAccum; // Accumulator for dragging modification. Always high-precision, not rounded by end-user precision settings float DragSpeedDefaultRatio; // If speed == 0.0f, uses (max-min) * DragSpeedDefaultRatio - ImVec2 ScrollbarClickDeltaToGrabCenter; // Distance between mouse and center of grab box, normalized in parent space. Use storage? + float ScrollbarClickDeltaToGrabCenter; // Distance between mouse and center of grab box, normalized in parent space. Use storage? int TooltipOverrideCount; ImVector PrivateClipboard; // If no custom clipboard handler is defined @@ -1092,7 +1092,7 @@ struct ImGuiContext DragCurrentAccumDirty = false; DragCurrentAccum = 0.0f; DragSpeedDefaultRatio = 1.0f / 100.0f; - ScrollbarClickDeltaToGrabCenter = ImVec2(0.0f, 0.0f); + ScrollbarClickDeltaToGrabCenter = 0.0f; TooltipOverrideCount = 0; MultiSelectScopeId = 0; @@ -1551,6 +1551,7 @@ namespace ImGui IMGUI_API bool CollapseButton(ImGuiID id, const ImVec2& pos); IMGUI_API bool ArrowButtonEx(const char* str_id, ImGuiDir dir, ImVec2 size_arg, ImGuiButtonFlags flags); IMGUI_API void Scrollbar(ImGuiAxis axis); + IMGUI_API bool ScrollbarEx(const ImRect& bb, ImGuiID id, ImGuiAxis axis, float* p_scroll_v, float avail_v, float contents_v, ImDrawCornerFlags rounding_corners); IMGUI_API ImGuiID GetScrollbarID(ImGuiWindow* window, ImGuiAxis axis); IMGUI_API void SeparatorEx(ImGuiSeparatorFlags flags); diff --git a/imgui_widgets.cpp b/imgui_widgets.cpp index 2d00300e1..2b4368bcf 100644 --- a/imgui_widgets.cpp +++ b/imgui_widgets.cpp @@ -380,6 +380,7 @@ void ImGui::BulletTextV(const char* fmt, va_list args) // - ArrowButton() // - CloseButton() [Internal] // - CollapseButton() [Internal] +// - ScrollbarEx() [Internal] // - Scrollbar() [Internal] // - Image() // - ImageButton() @@ -777,6 +778,98 @@ ImGuiID ImGui::GetScrollbarID(ImGuiWindow* window, ImGuiAxis axis) // - We handle absolute seeking (when first clicking outside the grab) and relative manipulation (afterward or when clicking inside the grab) // - We store values as normalized ratio and in a form that allows the window content to change while we are holding on a scrollbar // - We handle both horizontal and vertical scrollbars, which makes the terminology not ideal. +// Still, the code should probably be made simpler.. +bool ImGui::ScrollbarEx(const ImRect& bb_frame, ImGuiID id, ImGuiAxis axis, float* p_scroll_v, float size_avail_v, float size_contents_v, ImDrawCornerFlags rounding_corners) +{ + ImGuiContext& g = *GImGui; + ImGuiWindow* window = g.CurrentWindow; + if (window->SkipItems) + return false; + + const float bb_frame_width = bb_frame.GetWidth(); + const float bb_frame_height = bb_frame.GetHeight(); + if (bb_frame_width <= 0.0f || bb_frame_height <= 0.0f) + return false; + + // When we are too small, start hiding and disabling the grab (this reduce visual noise on very small window and facilitate using the resize grab) + float alpha = 1.0f; + if ((axis == ImGuiAxis_Y) && bb_frame_height < g.FontSize + g.Style.FramePadding.y * 2.0f) + alpha = ImSaturate((bb_frame_height - g.FontSize) / (g.Style.FramePadding.y * 2.0f)); + if (alpha <= 0.0f) + return false; + + const ImGuiStyle& style = g.Style; + const bool allow_interaction = (alpha >= 1.0f); + const bool horizontal = (axis == ImGuiAxis_X); + + ImRect bb = bb_frame; + bb.Expand(ImVec2(-ImClamp((float)(int)((bb_frame_width - 2.0f) * 0.5f), 0.0f, 3.0f), -ImClamp((float)(int)((bb_frame_height - 2.0f) * 0.5f), 0.0f, 3.0f))); + + // V denote the main, longer axis of the scrollbar (= height for a vertical scrollbar) + const float scrollbar_size_v = horizontal ? bb.GetWidth() : bb.GetHeight(); + + // Calculate the height of our grabbable box. It generally represent the amount visible (vs the total scrollable amount) + // But we maintain a minimum size in pixel to allow for the user to still aim inside. + IM_ASSERT(ImMax(size_contents_v, size_avail_v) > 0.0f); // Adding this assert to check if the ImMax(XXX,1.0f) is still needed. PLEASE CONTACT ME if this triggers. + const float win_size_v = ImMax(ImMax(size_contents_v, size_avail_v), 1.0f); + const float grab_h_pixels = ImClamp(scrollbar_size_v * (size_avail_v / win_size_v), style.GrabMinSize, scrollbar_size_v); + const float grab_h_norm = grab_h_pixels / scrollbar_size_v; + + // Handle input right away. None of the code of Begin() is relying on scrolling position before calling Scrollbar(). + bool held = false; + bool hovered = false; + ButtonBehavior(bb, id, &hovered, &held, ImGuiButtonFlags_NoNavFocus); + + float scroll_max = ImMax(1.0f, size_contents_v - size_avail_v); + float scroll_ratio = ImSaturate(*p_scroll_v / scroll_max); + float grab_v_norm = scroll_ratio * (scrollbar_size_v - grab_h_pixels) / scrollbar_size_v; + if (held && allow_interaction && grab_h_norm < 1.0f) + { + float scrollbar_pos_v = horizontal ? bb.Min.x : bb.Min.y; + float mouse_pos_v = horizontal ? g.IO.MousePos.x : g.IO.MousePos.y; + + // Click position in scrollbar normalized space (0.0f->1.0f) + const float clicked_v_norm = ImSaturate((mouse_pos_v - scrollbar_pos_v) / scrollbar_size_v); + SetHoveredID(id); + + bool seek_absolute = false; + if (g.ActiveIdIsJustActivated) + { + // On initial click calculate the distance between mouse and the center of the grab + seek_absolute = (clicked_v_norm < grab_v_norm || clicked_v_norm > grab_v_norm + grab_h_norm); + if (seek_absolute) + g.ScrollbarClickDeltaToGrabCenter = 0.0f; + else + g.ScrollbarClickDeltaToGrabCenter = clicked_v_norm - grab_v_norm - grab_h_norm * 0.5f; + } + + // Apply scroll + // It is ok to modify Scroll here because we are being called in Begin() after the calculation of SizeContents and before setting up our starting position + const float scroll_v_norm = ImSaturate((clicked_v_norm - g.ScrollbarClickDeltaToGrabCenter - grab_h_norm * 0.5f) / (1.0f - grab_h_norm)); + *p_scroll_v = (float)(int)(0.5f + scroll_v_norm * scroll_max);//(win_size_contents_v - win_size_v)); + + // Update values for rendering + scroll_ratio = ImSaturate(*p_scroll_v / scroll_max); + grab_v_norm = scroll_ratio * (scrollbar_size_v - grab_h_pixels) / scrollbar_size_v; + + // Update distance to grab now that we have seeked and saturated + if (seek_absolute) + g.ScrollbarClickDeltaToGrabCenter = clicked_v_norm - grab_v_norm - grab_h_norm * 0.5f; + } + + // Render + window->DrawList->AddRectFilled(bb_frame.Min, bb_frame.Max, GetColorU32(ImGuiCol_ScrollbarBg), window->WindowRounding, rounding_corners); + const ImU32 grab_col = GetColorU32(held ? ImGuiCol_ScrollbarGrabActive : hovered ? ImGuiCol_ScrollbarGrabHovered : ImGuiCol_ScrollbarGrab, alpha); + ImRect grab_rect; + if (horizontal) + grab_rect = ImRect(ImLerp(bb.Min.x, bb.Max.x, grab_v_norm), bb.Min.y, ImLerp(bb.Min.x, bb.Max.x, grab_v_norm) + grab_h_pixels, bb.Max.y); + else + grab_rect = ImRect(bb.Min.x, ImLerp(bb.Min.y, bb.Max.y, grab_v_norm), bb.Max.x, ImLerp(bb.Min.y, bb.Max.y, grab_v_norm) + grab_h_pixels); + window->DrawList->AddRectFilled(grab_rect.Min, grab_rect.Max, grab_col, style.ScrollbarRounding); + + return held; +} + void ImGui::Scrollbar(ImGuiAxis axis) { ImGuiContext& g = *GImGui; @@ -787,115 +880,31 @@ void ImGui::Scrollbar(ImGuiAxis axis) const ImGuiID id = GetScrollbarID(window, axis); KeepAliveID(id); - // Render background - bool other_scrollbar = (horizontal ? window->ScrollbarY : window->ScrollbarX); - float other_scrollbar_size_w = other_scrollbar ? style.ScrollbarSize : 0.0f; - const ImRect host_rect = window->Rect(); + // Calculate our bounding box (FIXME: This is messy, should be made simpler using e.g. InnerRect/WorkRect data). + const float other_scrollbar_size = window->ScrollbarSizes[axis]; + const ImRect win_rect = window->Rect(); const float border_size = window->WindowBorderSize; ImRect bb = horizontal - ? ImRect(host_rect.Min.x + border_size, host_rect.Max.y - style.ScrollbarSize, host_rect.Max.x - other_scrollbar_size_w - border_size, host_rect.Max.y - border_size) - : ImRect(host_rect.Max.x - style.ScrollbarSize, host_rect.Min.y + border_size, host_rect.Max.x - border_size, host_rect.Max.y - other_scrollbar_size_w - border_size); - bb.Min.x = ImMax(host_rect.Min.x, bb.Min.x); // Handle case where the host rectangle is smaller than the scrollbar - bb.Min.y = ImMax(host_rect.Min.y, bb.Min.y); + ? ImRect(win_rect.Min.x + border_size, win_rect.Max.y - style.ScrollbarSize, win_rect.Max.x - other_scrollbar_size - border_size, win_rect.Max.y - border_size) + : ImRect(win_rect.Max.x - style.ScrollbarSize, win_rect.Min.y + border_size, win_rect.Max.x - border_size, win_rect.Max.y - other_scrollbar_size - border_size); + bb.Min.x = ImMax(win_rect.Min.x, bb.Min.x); // Handle case where the host rectangle is smaller than the scrollbar + bb.Min.y = ImMax(win_rect.Min.y, bb.Min.y); if (!horizontal) bb.Min.y += window->TitleBarHeight() + ((window->Flags & ImGuiWindowFlags_MenuBar) ? window->MenuBarHeight() : 0.0f); // FIXME: InnerRect? - const float bb_width = bb.GetWidth(); - const float bb_height = bb.GetHeight(); - if (bb_width <= 0.0f || bb_height <= 0.0f) - return; - - // When we are too small, start hiding and disabling the grab (this reduce visual noise on very small window and facilitate using the resize grab) - float alpha = 1.0f; - if ((axis == ImGuiAxis_Y) && bb_height < g.FontSize + g.Style.FramePadding.y * 2.0f) - { - alpha = ImSaturate((bb_height - g.FontSize) / (g.Style.FramePadding.y * 2.0f)); - if (alpha <= 0.0f) - return; - } - const bool allow_interaction = (alpha >= 1.0f); - - int window_rounding_corners; + // Select rounding + ImDrawCornerFlags rounding_corners; if (horizontal) - window_rounding_corners = ImDrawCornerFlags_BotLeft | (other_scrollbar ? 0 : ImDrawCornerFlags_BotRight); + rounding_corners = ImDrawCornerFlags_BotLeft; else - window_rounding_corners = (((window->Flags & ImGuiWindowFlags_NoTitleBar) && !(window->Flags & ImGuiWindowFlags_MenuBar)) ? ImDrawCornerFlags_TopRight : 0) | (other_scrollbar ? 0 : ImDrawCornerFlags_BotRight); - window->DrawList->AddRectFilled(bb.Min, bb.Max, GetColorU32(ImGuiCol_ScrollbarBg), window->WindowRounding, window_rounding_corners); - bb.Expand(ImVec2(-ImClamp((float)(int)((bb_width - 2.0f) * 0.5f), 0.0f, 3.0f), -ImClamp((float)(int)((bb_height - 2.0f) * 0.5f), 0.0f, 3.0f))); + rounding_corners = ((window->Flags & ImGuiWindowFlags_NoTitleBar) && !(window->Flags & ImGuiWindowFlags_MenuBar)) ? ImDrawCornerFlags_TopRight : 0; + if (other_scrollbar_size <= 0.0f) + rounding_corners |= ImDrawCornerFlags_BotRight; - // V denote the main, longer axis of the scrollbar (= height for a vertical scrollbar) - float scrollbar_size_v = horizontal ? bb.GetWidth() : bb.GetHeight(); - float scroll_v = horizontal ? window->Scroll.x : window->Scroll.y; - float win_size_avail_v = (horizontal ? window->SizeFull.x : window->SizeFull.y) - other_scrollbar_size_w; - float win_size_contents_v = horizontal ? window->SizeContents.x : window->SizeContents.y; - - // Calculate the height of our grabbable box. It generally represent the amount visible (vs the total scrollable amount) - // But we maintain a minimum size in pixel to allow for the user to still aim inside. - IM_ASSERT(ImMax(win_size_contents_v, win_size_avail_v) > 0.0f); // Adding this assert to check if the ImMax(XXX,1.0f) is still needed. PLEASE CONTACT ME if this triggers. - const float win_size_v = ImMax(ImMax(win_size_contents_v, win_size_avail_v), 1.0f); - const float grab_h_pixels = ImClamp(scrollbar_size_v * (win_size_avail_v / win_size_v), style.GrabMinSize, scrollbar_size_v); - const float grab_h_norm = grab_h_pixels / scrollbar_size_v; - - // Handle input right away. None of the code of Begin() is relying on scrolling position before calling Scrollbar(). - bool held = false; - bool hovered = false; - const bool previously_held = (g.ActiveId == id); - ButtonBehavior(bb, id, &hovered, &held, ImGuiButtonFlags_NoNavFocus); - - float scroll_max = ImMax(1.0f, win_size_contents_v - win_size_avail_v); - float scroll_ratio = ImSaturate(scroll_v / scroll_max); - float grab_v_norm = scroll_ratio * (scrollbar_size_v - grab_h_pixels) / scrollbar_size_v; - if (held && allow_interaction && grab_h_norm < 1.0f) - { - float scrollbar_pos_v = horizontal ? bb.Min.x : bb.Min.y; - float mouse_pos_v = horizontal ? g.IO.MousePos.x : g.IO.MousePos.y; - float* click_delta_to_grab_center_v = horizontal ? &g.ScrollbarClickDeltaToGrabCenter.x : &g.ScrollbarClickDeltaToGrabCenter.y; - - // Click position in scrollbar normalized space (0.0f->1.0f) - const float clicked_v_norm = ImSaturate((mouse_pos_v - scrollbar_pos_v) / scrollbar_size_v); - SetHoveredID(id); - - bool seek_absolute = false; - if (!previously_held) - { - // On initial click calculate the distance between mouse and the center of the grab - if (clicked_v_norm >= grab_v_norm && clicked_v_norm <= grab_v_norm + grab_h_norm) - { - *click_delta_to_grab_center_v = clicked_v_norm - grab_v_norm - grab_h_norm*0.5f; - } - else - { - seek_absolute = true; - *click_delta_to_grab_center_v = 0.0f; - } - } - - // Apply scroll - // It is ok to modify Scroll here because we are being called in Begin() after the calculation of SizeContents and before setting up our starting position - const float scroll_v_norm = ImSaturate((clicked_v_norm - *click_delta_to_grab_center_v - grab_h_norm*0.5f) / (1.0f - grab_h_norm)); - scroll_v = (float)(int)(0.5f + scroll_v_norm * scroll_max);//(win_size_contents_v - win_size_v)); - if (horizontal) - window->Scroll.x = scroll_v; - else - window->Scroll.y = scroll_v; - - // Update values for rendering - scroll_ratio = ImSaturate(scroll_v / scroll_max); - grab_v_norm = scroll_ratio * (scrollbar_size_v - grab_h_pixels) / scrollbar_size_v; - - // Update distance to grab now that we have seeked and saturated - if (seek_absolute) - *click_delta_to_grab_center_v = clicked_v_norm - grab_v_norm - grab_h_norm*0.5f; - } - - // Render grab - const ImU32 grab_col = GetColorU32(held ? ImGuiCol_ScrollbarGrabActive : hovered ? ImGuiCol_ScrollbarGrabHovered : ImGuiCol_ScrollbarGrab, alpha); - ImRect grab_rect; if (horizontal) - grab_rect = ImRect(ImLerp(bb.Min.x, bb.Max.x, grab_v_norm), bb.Min.y, ImMin(ImLerp(bb.Min.x, bb.Max.x, grab_v_norm) + grab_h_pixels, host_rect.Max.x), bb.Max.y); + ScrollbarEx(bb, id, axis, &window->Scroll.x, window->SizeFull.x - other_scrollbar_size, window->SizeContents.x, rounding_corners); else - grab_rect = ImRect(bb.Min.x, ImLerp(bb.Min.y, bb.Max.y, grab_v_norm), bb.Max.x, ImMin(ImLerp(bb.Min.y, bb.Max.y, grab_v_norm) + grab_h_pixels, host_rect.Max.y)); - window->DrawList->AddRectFilled(grab_rect.Min, grab_rect.Max, grab_col, style.ScrollbarRounding); + ScrollbarEx(bb, id, axis, &window->Scroll.y, window->SizeFull.y - other_scrollbar_size, window->SizeContents.y, rounding_corners); } void ImGui::Image(ImTextureID user_texture_id, const ImVec2& size, const ImVec2& uv0, const ImVec2& uv1, const ImVec4& tint_col, const ImVec4& border_col)