From 95fe11b5bf14f72fc70762347c583d089e619a65 Mon Sep 17 00:00:00 2001 From: omar Date: Wed, 26 Jul 2017 14:34:59 +0800 Subject: [PATCH] Added GetColorU32(u32) variant that does the style alpha multiply without a floating point round trip. Not 100% sure about that before the signature may seem ambiguous? But also make using imgui+drawlist more consistent in end-user extensions. --- imgui.cpp | 11 +++++++++++ imgui.h | 1 + 2 files changed, 12 insertions(+) diff --git a/imgui.cpp b/imgui.cpp index 3d84e83b..e8a7a7f5 100644 --- a/imgui.cpp +++ b/imgui.cpp @@ -1253,6 +1253,16 @@ ImU32 ImGui::GetColorU32(const ImVec4& col) return ColorConvertFloat4ToU32(c); } +ImU32 ImGui::GetColorU32(ImU32 col) +{ + float style_alpha = GImGui->Style.Alpha; + if (style_alpha >= 1.0f) + return col; + int a = (col & IM_COL32_A_MASK) >> IM_COL32_A_SHIFT; + a = (int)(a * style_alpha); // We don't need to clamp 0..255 because Style.Alpha is in 0..1 range. + return (col & ~IM_COL32_A_MASK) | (a << IM_COL32_A_SHIFT); +} + // Convert rgb floats ([0-1],[0-1],[0-1]) to hsv floats ([0-1],[0-1],[0-1]), from Foley & van Dam p592 // Optimized http://lolengine.net/blog/2013/01/13/fast-rgb-to-hsv void ImGui::ColorConvertRGBtoHSV(float r, float g, float b, float& out_h, float& out_s, float& out_v) @@ -2143,6 +2153,7 @@ void ImGui::NewFrame() IM_ASSERT(g.IO.Fonts->Fonts.Size > 0); // Font Atlas not created. Did you call io.Fonts->GetTexDataAsRGBA32 / GetTexDataAsAlpha8 ? IM_ASSERT(g.IO.Fonts->Fonts[0]->IsLoaded()); // Font Atlas not created. Did you call io.Fonts->GetTexDataAsRGBA32 / GetTexDataAsAlpha8 ? IM_ASSERT(g.Style.CurveTessellationTol > 0.0f); // Invalid style setting + IM_ASSERT(g.Style.Alpha >= 0.0f && g.Style.Alpha <= 1.0f); // Invalid style setting. Alpha cannot be negative (allows us to avoid a few clamps in color computations) if (!g.Initialized) { diff --git a/imgui.h b/imgui.h index 57ba915c..c6cf6515 100644 --- a/imgui.h +++ b/imgui.h @@ -190,6 +190,7 @@ namespace ImGui IMGUI_API ImVec2 GetFontTexUvWhitePixel(); // get UV coordinate for a while pixel, useful to draw custom shapes via the ImDrawList API IMGUI_API ImU32 GetColorU32(ImGuiCol idx, float alpha_mul = 1.0f); // retrieve given style color with style alpha applied and optional extra alpha multiplier IMGUI_API ImU32 GetColorU32(const ImVec4& col); // retrieve given color with style alpha applied + IMGUI_API ImU32 GetColorU32(ImU32 col); // retrieve given color with style alpha applied // Parameters stacks (current window) IMGUI_API void PushItemWidth(float item_width); // width of items for the common item+label case, pixels. 0.0f = default to ~2/3 of windows width, >0.0f: width in pixels, <0.0f align xx pixels to the right of window (so -1.0f always align width to the right side)