finish guides

implot.cpp

@@ -2486,17 +2486,23 @@ ImPlotLimits GetPlotQuery(int y_axis_in) {
 bool HorizontalGuide(const char* id, double* value, const ImVec4& col, float thickness) {
     ImPlotContext& gp = *GImPlot;
     IM_ASSERT_USER_ERROR(gp.CurrentPlot != NULL, "HorizontalGuide() needs to be called between BeginPlot() and EndPlot()!");
-    const float grab_size = 2*thickness;
+    const float grab_size = ImMax(6.0f, thickness);
     float xl = gp.BB_Plot.Min.x;
     float xr = gp.BB_Plot.Max.x;
-    float y  = PlotToPixels(0, *value).y;
+    float y  = IM_ROUND(PlotToPixels(0, *value).y);
-    ImU32 col32 = IsColorAuto(col) ? GetStyleColorU32(ImPlotCol_Query) : ImGui::ColorConvertFloat4ToU32(col);
-    PushPlotClipRect();
-    GetPlotDrawList()->AddLine(ImVec2(xl,y), ImVec2(xr,y), col32, thickness);
-    PopPlotClipRect();
     const bool outside = (y < gp.BB_Plot.Min.y - grab_size / 2 || y > gp.BB_Plot.Max.y + grab_size / 2);
     if (outside)
         return false;
+
+    float len = gp.Style.MajorTickLen.y;
+    ImVec4 color = IsColorAuto(col) ? ImGui::GetStyleColorVec4(ImGuiCol_Text) : col;
+    ImU32 col32 = ImGui::ColorConvertFloat4ToU32(color);
+    ImDrawList& DrawList = *GetPlotDrawList();
+
+    PushPlotClipRect();
+    DrawList.AddLine(ImVec2(xl,y), ImVec2(xr,y),     col32, thickness);
+    DrawList.AddLine(ImVec2(xl,y), ImVec2(xl+len,y), col32, 3*thickness);
+    DrawList.AddLine(ImVec2(xr,y), ImVec2(xr-len,y), col32, 3*thickness);
     ImVec2 old_cursor_pos = ImGui::GetCursorScreenPos();
     ImVec2 new_cursor_pos = ImVec2(xl, y - grab_size / 2.0f);
     ImGui::SetItemAllowOverlap();
@@ -2505,7 +2511,23 @@ bool HorizontalGuide(const char* id, double* value, const ImVec4& col, float thi
     ImGui::SetCursorScreenPos(old_cursor_pos);
     if (ImGui::IsItemHovered() || ImGui::IsItemActive()) {
         ImGui::SetMouseCursor(ImGuiMouseCursor_ResizeNS);
+        int yax = GetCurrentYAxis();
+        double range_y = gp.YTicks[yax].Size > 1 ? (gp.YTicks[yax].Ticks[1].PlotPos - gp.YTicks[yax].Ticks[0].PlotPos) : gp.CurrentPlot->YAxis[yax].Range.Size();
+        char buf[32];
+        snprintf(buf, 32, "%s = %.*f", id, Precision(range_y), *value);
+        ImVec2 size = ImGui::CalcTextSize(buf);
+        const int pad = 2;
+        if (yax == 0) {
+            DrawList.AddRectFilled(ImVec2(xl,y-pad-size.y/2), ImVec2(xl + size.x + 2 * pad, y+pad+size.y/2), col32);
+            DrawList.AddText(ImVec2(xl+pad,y-size.y/2),CalcTextColor(color),buf);
+        }
+        else {
+            DrawList.AddRectFilled(ImVec2(xr-size.x-2*pad,y-pad-size.y/2), ImVec2(xr, y+pad+size.y/2), col32);
+            DrawList.AddText(ImVec2(xr-size.x-pad,y-size.y/2),CalcTextColor(color),buf);
+        }
     }
+    PopPlotClipRect();
+
     bool dragging = false;
     if (ImGui::IsItemActive() && ImGui::IsMouseDragging(0)) {
         *value = ImPlot::GetPlotMousePos().y;
@@ -2517,17 +2539,23 @@ bool HorizontalGuide(const char* id, double* value, const ImVec4& col, float thi
 bool VerticalGuide(const char* id, double* value, const ImVec4& col, float thickness) {
     ImPlotContext& gp = *GImPlot;
     IM_ASSERT_USER_ERROR(gp.CurrentPlot != NULL, "VerticalGuide() needs to be called between BeginPlot() and EndPlot()!");
-    const float grab_size = 2*thickness;
+    const float grab_size = ImMax(6.0f, thickness);
     float yt = gp.BB_Plot.Min.y;
     float yb = gp.BB_Plot.Max.y;
-    float x  = PlotToPixels(*value,0).x;
+    float x  = IM_ROUND(PlotToPixels(*value,0).x);
-    ImU32 col32 = IsColorAuto(col) ? GetStyleColorU32(ImPlotCol_Query) : ImGui::ColorConvertFloat4ToU32(col);
-    PushPlotClipRect();
-    GetPlotDrawList()->AddLine(ImVec2(x,yt), ImVec2(x,yb), col32, thickness);
-    PopPlotClipRect();
     const bool outside = (x < gp.BB_Plot.Min.x - grab_size / 2 || x > gp.BB_Plot.Max.x + grab_size / 2);
     if (outside)
         return false;
+
+    float len = gp.Style.MajorTickLen.x;
+    ImVec4 color = IsColorAuto(col) ? ImGui::GetStyleColorVec4(ImGuiCol_Text) : col;
+    ImU32 col32 = ImGui::ColorConvertFloat4ToU32(color);
+    ImDrawList& DrawList = *GetPlotDrawList();
+
+    PushPlotClipRect();
+    DrawList.AddLine(ImVec2(x,yt), ImVec2(x,yb),     col32, thickness);
+    DrawList.AddLine(ImVec2(x,yt), ImVec2(x,yt+len), col32, 3*thickness);
+    DrawList.AddLine(ImVec2(x,yb), ImVec2(x,yb-len), col32, 3*thickness);
     ImVec2 old_cursor_pos = ImGui::GetCursorScreenPos();
     ImVec2 new_cursor_pos = ImVec2(x - grab_size / 2.0f, yt);
     ImGui::SetItemAllowOverlap();
@@ -2536,7 +2564,16 @@ bool VerticalGuide(const char* id, double* value, const ImVec4& col, float thick
     ImGui::SetCursorScreenPos(old_cursor_pos);
     if (ImGui::IsItemHovered() || ImGui::IsItemActive()) {
         ImGui::SetMouseCursor(ImGuiMouseCursor_ResizeEW);
+        double range_x = gp.XTicks.Size > 1 ? (gp.XTicks.Ticks[1].PlotPos - gp.XTicks.Ticks[0].PlotPos) : gp.CurrentPlot->XAxis.Range.Size();
+        char buf[32];
+        snprintf(buf, 32, "%s = %.*f", id, Precision(range_x), *value);
+        ImVec2 size = ImGui::CalcTextSize(buf);
+        const int pad = 2;
+        DrawList.AddRectFilled(ImVec2(x - size.x/2 - pad, yb - size.y - 2*pad), ImVec2(x + pad + size.x/2, yb), col32);
+        DrawList.AddText(ImVec2(x - size.x/2, yb - size.y - pad), CalcTextColor(color), buf);
     }
+    PopPlotClipRect();
+
     bool dragging = false;
     if (ImGui::IsItemActive() && ImGui::IsMouseDragging(0)) {
         *value = ImPlot::GetPlotMousePos().x;

implot.h

@@ -463,10 +463,10 @@ IMPLOT_API bool IsPlotQueried();
 // Returns the current plot query bounds.
 IMPLOT_API ImPlotLimits GetPlotQuery(int y_axis = IMPLOT_AUTO);
 
-// Shows a draggable horizontal guide line.
+// Shows a draggable horizontal guide line. #col defaults to ImGuiCol_Text.
-IMPLOT_API bool HorizontalGuide(const char* id, double* value, const ImVec4& col = IMPLOT_AUTO_COL, float thickness = 2);
+IMPLOT_API bool HorizontalGuide(const char* id, double* y_value, const ImVec4& col = IMPLOT_AUTO_COL, float thickness = 1);
-// Shows a draggable vertical guide line.
+// Shows a draggable vertical guide line. #col defaults to ImGuiCol_Text.
-IMPLOT_API bool VerticalGuide(const char* id, double* value, const ImVec4& col = IMPLOT_AUTO_COL, float thickness = 2);
+IMPLOT_API bool VerticalGuide(const char* id, double* x_value, const ImVec4& col = IMPLOT_AUTO_COL, float thickness = 1);
 
 //-----------------------------------------------------------------------------
 // Plot and Item Styling

implot_demo.cpp

@@ -806,18 +806,27 @@ void ShowDemoWindow(bool* p_open) {
     }
     //-------------------------------------------------------------------------
     if (ImGui::CollapsingHeader("Guide Lines")) {
-        static double v1 = 0.2;
+        ImGui::BulletText("Click and drag the horizontal and vertical guide lines.");
-        static double v2 = 0.6;
+        static double x1 = 0.2;
-        static double h1 = 0.25;
+        static double x2 = 0.8;
-        static double h2 = 0.75;
+        static double y1 = 0.25;
-        static double h3 = 0.5;
+        static double y2 = 0.75;
+        static double f = 0.1;
         if (ImPlot::BeginPlot("##guides",0,0,ImVec2(-1,0),ImPlotFlags_YAxis2)) {
-            ImPlot::VerticalGuide("v1",&v1, ImVec4(0,1,0,1));
+            ImPlot::VerticalGuide("x1",&x1);
-            ImPlot::VerticalGuide("v2",&v2, ImVec4(0,1,0,1));
+            ImPlot::VerticalGuide("x2",&x2);
-            ImPlot::HorizontalGuide("h1",&h1, ImVec4(1,0,0,1));
+            ImPlot::HorizontalGuide("y1",&y1);
-            ImPlot::HorizontalGuide("h2",&h2, ImVec4(1,0,0,1));
+            ImPlot::HorizontalGuide("y2",&y2);
             ImPlot::SetPlotYAxis(1);
-            ImPlot::HorizontalGuide("h3",&h3, ImVec4(1,1,0,1));
+            ImPlot::HorizontalGuide("f",&f, ImVec4(1,0.5f,1,1));
+
+            ImPlot::SetPlotYAxis(0);
+            double xs[1000], ys[1000];
+            for (int i = 0; i < 1000; ++i) {
+                xs[i] = (x2+x1)/2+abs(x2-x1)*(i/990.0f - 0.5f);
+                ys[i] = (y1+y2)/2+abs(y2-y1)/2*sin(f*i/10);
+            }
+            ImPlot::PlotLine("Why Not?", xs, ys, 1000);
             ImPlot::EndPlot();
         }
     }