From ab5def6ad85c756638014692c9f8d2005cc7adc7 Mon Sep 17 00:00:00 2001 From: ocornut Date: Sun, 20 Sep 2015 12:02:17 +0200 Subject: [PATCH] PlotHistogram: Minimum bar width ensure better rendering with lots of points (~related to #342) --- imgui.cpp | 28 ++++++++++++++++++---------- 1 file changed, 18 insertions(+), 10 deletions(-) diff --git a/imgui.cpp b/imgui.cpp index eac6a26b..3b6e8a21 100644 --- a/imgui.cpp +++ b/imgui.cpp @@ -6604,7 +6604,7 @@ void ImGui::PlotEx(ImGuiPlotType plot_type, const char* label, float (*values_ge float v0 = values_getter(data, (0 + values_offset) % values_count); float t0 = 0.0f; - ImVec2 p0 = ImVec2( t0, 1.0f - ImSaturate((v0 - scale_min) / (scale_max - scale_min)) ); + ImVec2 tp0 = ImVec2( t0, 1.0f - ImSaturate((v0 - scale_min) / (scale_max - scale_min)) ); // Point in the normalized space of our target rectangle const ImU32 col_base = window->Color((plot_type == ImGuiPlotType_Lines) ? ImGuiCol_PlotLines : ImGuiCol_PlotHistogram); const ImU32 col_hovered = window->Color((plot_type == ImGuiPlotType_Lines) ? ImGuiCol_PlotLinesHovered : ImGuiCol_PlotHistogramHovered); @@ -6612,19 +6612,27 @@ void ImGui::PlotEx(ImGuiPlotType plot_type, const char* label, float (*values_ge for (int n = 0; n < res_w; n++) { const float t1 = t0 + t_step; - const int v_idx = (int)(t0 * item_count + 0.5f); - IM_ASSERT(v_idx >= 0 && v_idx < values_count); - const float v1 = values_getter(data, (v_idx + values_offset + 1) % values_count); - const ImVec2 p1 = ImVec2( t1, 1.0f - ImSaturate((v1 - scale_min) / (scale_max - scale_min)) ); - - // NB- Draw calls are merged together by the DrawList system. + const int v1_idx = (int)(t0 * item_count + 0.5f); + IM_ASSERT(v1_idx >= 0 && v1_idx < values_count); + const float v1 = values_getter(data, (v1_idx + values_offset + 1) % values_count); + const ImVec2 tp1 = ImVec2( t1, 1.0f - ImSaturate((v1 - scale_min) / (scale_max - scale_min)) ); + + // NB: Draw calls are merged together by the DrawList system. Still, we should render our batch are lower level to save a bit of CPU. + ImVec2 pos0 = ImLerp(inner_bb.Min, inner_bb.Max, tp0); + ImVec2 pos1 = ImLerp(inner_bb.Min, inner_bb.Max, (plot_type == ImGuiPlotType_Lines) ? tp1 : ImVec2(tp1.x, 1.0f)); if (plot_type == ImGuiPlotType_Lines) - window->DrawList->AddLine(ImLerp(inner_bb.Min, inner_bb.Max, p0), ImLerp(inner_bb.Min, inner_bb.Max, p1), v_hovered == v_idx ? col_hovered : col_base); + { + window->DrawList->AddLine(pos0, pos1, v_hovered == v1_idx ? col_hovered : col_base); + } else if (plot_type == ImGuiPlotType_Histogram) - window->DrawList->AddRectFilled(ImLerp(inner_bb.Min, inner_bb.Max, p0), ImLerp(inner_bb.Min, inner_bb.Max, ImVec2(p1.x, 1.0f))+ImVec2(-1,0), v_hovered == v_idx ? col_hovered : col_base); + { + if (pos1.x >= pos0.x + 2.0f) + pos1.x -= 1.0f; + window->DrawList->AddRectFilled(pos0, pos1, v_hovered == v1_idx ? col_hovered : col_base); + } t0 = t1; - p0 = p1; + tp0 = tp1; } // Text overlay