diff --git a/imgui.cpp b/imgui.cpp index e133fd1a..ecb3d7be 100644 --- a/imgui.cpp +++ b/imgui.cpp @@ -7363,6 +7363,19 @@ void ImGui::EndGroup() // [SECTION] SCROLLING //----------------------------------------------------------------------------- +// Helper to snap on edges when aiming at an item very close to the edge, +// So the difference between WindowPadding and ItemSpacing will be in the visible area after scrolling. +// When we refactor the scrolling API this may be configurable with a flag? +// Note that the effect for this won't be visible on X axis with default Style settings as WindowPadding.x == ItemSpacing.x by default. +static float CalcScrollEdgeSnap(float target, float snap_min, float snap_max, float snap_threshold, float center_ratio) +{ + if (target <= snap_min + snap_threshold) + return ImLerp(snap_min, target, center_ratio); + if (target >= snap_max - snap_threshold) + return ImLerp(target, snap_max, center_ratio); + return target; +} + static ImVec2 CalcNextScrollFromScrollTargetAndClamp(ImGuiWindow* window) { ImVec2 scroll = window->Scroll; @@ -7370,6 +7383,10 @@ static ImVec2 CalcNextScrollFromScrollTargetAndClamp(ImGuiWindow* window) { float center_x_ratio = window->ScrollTargetCenterRatio.x; float scroll_target_x = window->ScrollTarget.x; + float snap_x_min = 0.0f; + float snap_x_max = window->ScrollMax.x + window->Size.x; + if (window->ScrollTargetEdgeSnapDist.x > 0.0f) + scroll_target_x = CalcScrollEdgeSnap(scroll_target_x, snap_x_min, snap_x_max, window->ScrollTargetEdgeSnapDist.x, center_x_ratio); scroll.x = scroll_target_x - center_x_ratio * (window->SizeFull.x - window->ScrollbarSizes.x); } if (window->ScrollTarget.y < FLT_MAX) @@ -7377,6 +7394,10 @@ static ImVec2 CalcNextScrollFromScrollTargetAndClamp(ImGuiWindow* window) float decoration_up_height = window->TitleBarHeight() + window->MenuBarHeight(); float center_y_ratio = window->ScrollTargetCenterRatio.y; float scroll_target_y = window->ScrollTarget.y; + float snap_y_min = 0.0f; + float snap_y_max = window->ScrollMax.y + window->Size.y - decoration_up_height; + if (window->ScrollTargetEdgeSnapDist.y > 0.0f) + scroll_target_y = CalcScrollEdgeSnap(scroll_target_y, snap_y_min, snap_y_max, window->ScrollTargetEdgeSnapDist.y, center_y_ratio); scroll.y = scroll_target_y - center_y_ratio * (window->SizeFull.y - window->ScrollbarSizes.y - decoration_up_height); } scroll.x = IM_FLOOR(ImMax(scroll.x, 0.0f)); @@ -7447,12 +7468,14 @@ void ImGui::SetScrollX(ImGuiWindow* window, float scroll_x) { window->ScrollTarget.x = scroll_x; window->ScrollTargetCenterRatio.x = 0.0f; + window->ScrollTargetEdgeSnapDist.x = 0.0f; } void ImGui::SetScrollY(ImGuiWindow* window, float scroll_y) { window->ScrollTarget.y = scroll_y; window->ScrollTargetCenterRatio.y = 0.0f; + window->ScrollTargetEdgeSnapDist.y = 0.0f; } void ImGui::SetScrollX(float scroll_x) @@ -7482,6 +7505,7 @@ void ImGui::SetScrollFromPosX(ImGuiWindow* window, float local_x, float center_x IM_ASSERT(center_x_ratio >= 0.0f && center_x_ratio <= 1.0f); window->ScrollTarget.x = IM_FLOOR(local_x + window->Scroll.x); // Convert local position to scroll offset window->ScrollTargetCenterRatio.x = center_x_ratio; + window->ScrollTargetEdgeSnapDist.x = 0.0f; } void ImGui::SetScrollFromPosY(ImGuiWindow* window, float local_y, float center_y_ratio) @@ -7490,6 +7514,7 @@ void ImGui::SetScrollFromPosY(ImGuiWindow* window, float local_y, float center_y local_y -= window->TitleBarHeight() + window->MenuBarHeight(); // FIXME: Would be nice to have a more standardized access to our scrollable/client rect window->ScrollTarget.y = IM_FLOOR(local_y + window->Scroll.y); // Convert local position to scroll offset window->ScrollTargetCenterRatio.y = center_y_ratio; + window->ScrollTargetEdgeSnapDist.y = 0.0f; } void ImGui::SetScrollFromPosX(float local_x, float center_x_ratio) @@ -7504,19 +7529,6 @@ void ImGui::SetScrollFromPosY(float local_y, float center_y_ratio) SetScrollFromPosY(g.CurrentWindow, local_y, center_y_ratio); } -// Tweak: snap on edges when aiming at an item very close to the edge, -// So the difference between WindowPadding and ItemSpacing will be in the visible area after scrolling. -// When we refactor the scrolling API this may be configurable with a flag? -// Note that the effect for this won't be visible on X axis with default Style settings as WindowPadding.x == ItemSpacing.x by default. -static float CalcScrollSnap(float target, float snap_min, float snap_max, float snap_threshold, float center_ratio) -{ - if (target <= snap_min + snap_threshold) - return ImLerp(snap_min, target, center_ratio); - if (target >= snap_max - snap_threshold) - return ImLerp(target, snap_max, center_ratio); - return target; -} - // center_x_ratio: 0.0f left of last item, 0.5f horizontal center of last item, 1.0f right of last item. void ImGui::SetScrollHereX(float center_x_ratio) { @@ -7524,14 +7536,10 @@ void ImGui::SetScrollHereX(float center_x_ratio) ImGuiWindow* window = g.CurrentWindow; float spacing_x = g.Style.ItemSpacing.x; float target_pos_x = ImLerp(window->DC.LastItemRect.Min.x - spacing_x, window->DC.LastItemRect.Max.x + spacing_x, center_x_ratio); + SetScrollFromPosX(window, target_pos_x - window->Pos.x, center_x_ratio); // Convert from absolute to local pos // Tweak: snap on edges when aiming at an item very close to the edge - const float snap_x_threshold = ImMax(0.0f, window->WindowPadding.x - spacing_x); - const float snap_x_min = window->DC.CursorStartPos.x - window->WindowPadding.x; - const float snap_x_max = window->DC.CursorStartPos.x + window->ContentSize.x + window->WindowPadding.x; - target_pos_x = CalcScrollSnap(target_pos_x, snap_x_min, snap_x_max, snap_x_threshold, center_x_ratio); - - SetScrollFromPosX(window, target_pos_x - window->Pos.x, center_x_ratio); // Convert from absolute to local pos + window->ScrollTargetEdgeSnapDist.x = ImMax(0.0f, window->WindowPadding.x - spacing_x); } // center_y_ratio: 0.0f top of last item, 0.5f vertical center of last item, 1.0f bottom of last item. @@ -7541,14 +7549,10 @@ void ImGui::SetScrollHereY(float center_y_ratio) ImGuiWindow* window = g.CurrentWindow; float spacing_y = g.Style.ItemSpacing.y; float target_pos_y = ImLerp(window->DC.CursorPosPrevLine.y - spacing_y, window->DC.CursorPosPrevLine.y + window->DC.PrevLineSize.y + spacing_y, center_y_ratio); + SetScrollFromPosY(window, target_pos_y - window->Pos.y, center_y_ratio); // Convert from absolute to local pos // Tweak: snap on edges when aiming at an item very close to the edge - const float snap_y_threshold = ImMax(0.0f, window->WindowPadding.y - spacing_y); - const float snap_y_min = window->DC.CursorStartPos.y - window->WindowPadding.y; - const float snap_y_max = window->DC.CursorStartPos.y + window->ContentSize.y + window->WindowPadding.y; - target_pos_y = CalcScrollSnap(target_pos_y, snap_y_min, snap_y_max, snap_y_threshold, center_y_ratio); - - SetScrollFromPosY(window, target_pos_y - window->Pos.y, center_y_ratio); // Convert from absolute to local pos + window->ScrollTargetEdgeSnapDist.y = ImMax(0.0f, window->WindowPadding.y - spacing_y); } //----------------------------------------------------------------------------- diff --git a/imgui_internal.h b/imgui_internal.h index b147c5a2..f6655bd5 100644 --- a/imgui_internal.h +++ b/imgui_internal.h @@ -1585,6 +1585,7 @@ struct IMGUI_API ImGuiWindow ImVec2 ScrollMax; ImVec2 ScrollTarget; // target scroll position. stored as cursor position with scrolling canceled out, so the highest point is always 0.0f. (FLT_MAX for no change) ImVec2 ScrollTargetCenterRatio; // 0.0f = scroll so that target position is at top, 0.5f = scroll so that target position is centered + ImVec2 ScrollTargetEdgeSnapDist; // 0.0f = no snapping, >0.0f snapping threshold ImVec2 ScrollbarSizes; // Size taken by each scrollbars on their smaller axis. Pay attention! ScrollbarSizes.x == width of the vertical scrollbar, ScrollbarSizes.y = height of the horizontal scrollbar. bool ScrollbarX, ScrollbarY; // Are scrollbars visible? bool Active; // Set to true on Begin(), unless Collapsed