From f7a723f6651d4c57f68182182e3bdfa29ab58824 Mon Sep 17 00:00:00 2001 From: omar Date: Sun, 15 Nov 2015 22:49:30 +0100 Subject: [PATCH] Updated Tips (markdown) --- Tips.md | 38 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) diff --git a/Tips.md b/Tips.md index 2d9ec31..474d09b 100644 --- a/Tips.md +++ b/Tips.md @@ -13,3 +13,41 @@ ImGui::BeginChild("##scrolling"); ImGui::SetScrollFromPosY(ImGui::GetCursorStartPos().y + (goto_addr / Rows) * line_height); ImGui::End(); ``` + +**Tip: use Stride for easily plotting a field in array of structures**
+https://github.com/ocornut/imgui/issues/271 + +Here I've got some code sampling joints of an animation as e.g 60 hz. +And I can plot that directly from the joint structure without copying the data around one more time + +```cpp +int stride = skel.getBoneCount() * sizeof(JointTransform); +ImGui::PlotLines("RightFoot y", &all_sampled_joints[skel.getBoneIndex("RightFoot")].translation.y, samples, 0, NULL, FLT_MAX, FLT_MAX, ImVec2(0,0), stride); +ImGui::PlotLines("RightToeBase y", &all_sampled_joints[skel.getBoneIndex("RightToeBase")].translation.y, samples, 0, NULL, FLT_MAX, FLT_MAX, ImVec2(0,0), stride); +ImGui::PlotLines("LeftFoot y", &all_sampled_joints[skel.getBoneIndex("LeftFoot")].translation.y, samples, 0, NULL, FLT_MAX, FLT_MAX, ImVec2(0,0), stride); +ImGui::PlotLines("LeftToeBase y", &all_sampled_joints[skel.getBoneIndex("LeftToeBase")].translation.y, samples, 0, NULL, FLT_MAX, FLT_MAX, ImVec2(0,0), stride); +``` + +![footsteps](https://cloud.githubusercontent.com/assets/8225057/8634511/66076f8e-27b8-11e5-9964-202bf4305802.PNG) + +**Tip: use c++11 lambas with Combo/ListBox/Plot functions** + +```cpp +void SelectBoneByName(const char* label, int* bone_idx, const Skeleton* skeleton) +{ + ImGui::Combo(label, bone_idx, + [](void* data, int idx, const char** out_text) { *out_text = skeleton->GetBoneName(idx); return *out_text != NULL; }, + (void*)skeleton, skeleton->GetBoneCount()); +} +``` + +```cpp +ImGui::PlotLines("Sin", [](void*data, int idx) { return sinf(idx*0.2f); }, NULL, 100); +ImGui::PlotLines("Cos", [](void*data, int idx) { return cosf(idx*0.2f); }, NULL, 100); +``` + +![plot func](https://cloud.githubusercontent.com/assets/8225057/8634531/b3281cd6-27b9-11e5-8bf8-ec9f1c67e866.PNG) + +Bit awkward with sample indices to plot an actual math function. Ideally here we could introduce variants of plot that use all floats. Will probably add something. + +Likewise for combo boxes, don't copy data around creating list of strings! Use a function to retrieve your data from whatever format it is naturally. The whole plot API is a little awkward and could be reworked along with adding some form of iterator scheme for sparse combo / list-box.