@ -23,10 +23,8 @@
- ISSUES & TODO LIST
- FREQUENTLY ASKED QUESTIONS ( FAQ ) , TIPS
- How can I help ?
- What is ImTextureID and how do I display an image ?
- I integrated Dear ImGui in my engine and the text or lines are blurry . .
- I integrated Dear ImGui in my engine and some elements are clipping or disappearing when I move windows around . .
- How can I have multiple widgets with the same label ? Can I have widget without a label ? ( Yes ) . A primer on labels / IDs .
- How can I dipslay an image ? What is ImTextureID , how does it works ?
- How can I have multiple widgets with the same label ? Can I have widget without a label ? ( Yes ) . A primer on labels and the ID stack .
- How can I tell when Dear ImGui wants my mouse / keyboard inputs VS when I can pass them to my application ?
- How can I load a different font than the default ?
- How can I easily use icons in my application ?
@ -34,6 +32,8 @@
- How can I display and input non - latin characters such as Chinese , Japanese , Korean , Cyrillic ?
- How can I preserve my Dear ImGui context across reloading a DLL ? ( loss of the global / static variables )
- How can I use the drawing facilities without an ImGui window ? ( using ImDrawList API )
- I integrated Dear ImGui in my engine and the text or lines are blurry . .
- I integrated Dear ImGui in my engine and some elements are clipping or disappearing when I move windows around . .
- ISSUES & TODO - LIST
- CODE
@ -374,10 +374,14 @@
= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
Q : How can I help ?
A : - If you are experienced enough with Dear ImGui and with C / C + + , look at the todo list and see how you want / can help !
- Become a Patron / donate ! Convince your company to become a Patron or provide serious funding for development time ! See http : //www.patreon.com/imgui
Q : What is ImTextureID and how do I display an image ?
A : - If you are experienced with Dear ImGui and C + + , look at the github issues , or TODO . txt and see how you want / can help !
- Convince your company to fund development time ! Individual users : you can also become a Patron ( patreon . com / imgui ) or donate on PayPal ! See README .
- Disclose your usage of dear imgui via a dev blog post , a tweet , a screenshot , a mention somewhere etc .
You may post screenshot or links in the gallery threads ( github . com / ocornut / imgui / issues / 1269 ) . Visuals are ideal as they inspire other programmers .
But even without visuals , disclosing your use of dear imgui help the library grow credibility , and help other teams and programmers with taking decisions .
- If you have issues or if you need to hack into the library , even if you don ' t expect any support it is useful that you share your issues ( on github or privately ) .
Q : How can I display an image ? What is ImTextureID , how does it works ?
A : ImTextureID is a void * used to pass renderer - agnostic texture references around until it hits your render function .
Dear ImGui knows nothing about what those bits represent , it just passes them around . It is up to you to decide what you want the void * to carry !
It could be an identifier to your OpenGL texture ( cast GLuint to void * ) , a pointer to your custom engine material ( cast MyMaterial * to void * ) , etc .
@ -386,26 +390,19 @@
( c + + tip : OpenGL uses integers to identify textures . You can safely store an integer into a void * , just cast it to void * , don ' t take it ' s address ! )
To display a custom image / texture within an ImGui window , you may use ImGui : : Image ( ) , ImGui : : ImageButton ( ) , ImDrawList : : AddImage ( ) functions .
Dear ImGui will generate the geometry and draw calls using the ImTextureID that you passed and which your renderer can use .
You may call ImGui : : ShowMetricsWindow ( ) to explore active draw lists and visualize / understand how the draw data is generated .
It is your responsibility to get textures uploaded to your GPU .
Q : I integrated Dear ImGui in my engine and the text or lines are blurry . .
A : In your Render function , try translating your projection matrix by ( 0.5f , 0.5f ) or ( 0.375f , 0.375f ) .
Also make sure your orthographic projection matrix and io . DisplaySize matches your actual framebuffer dimension .
Q : I integrated Dear ImGui in my engine and some elements are clipping or disappearing when I move windows around . .
A : You are probably mishandling the clipping rectangles in your render function .
Rectangles provided by ImGui are defined as ( x1 = left , y1 = top , x2 = right , y2 = bottom ) and NOT as ( x1 , y1 , width , height ) .
Q : Can I have multiple widgets with the same label ? Can I have widget without a label ?
A : Yes . A primer on the use of labels / IDs in Dear ImGui . .
A : Yes . A primer on labels and the ID stack . . .
- Elements that are clickable , such as Text ( ) items don ' t need an ID .
- Elements that are typically not clickable , such as Text ( ) items don ' t need an ID .
- Interactive widgets require state to be carried over multiple frames ( most typically Dear ImGui often needs to remember what is
the " active " widget ) . to do so they need a unique ID . unique ID are typically derived from a string label , an integer index or a pointer .
Button ( " OK " ) ; // Label = "OK", ID = hash of "OK"
Button ( " Cancel " ) ; // Label = "Cancel", ID = hash of "Cancel"
Button ( " OK " ) ; // Label = "OK", ID = hash of "OK"
Button ( " Cancel " ) ; // Label = "Cancel", ID = hash of "Cancel"
- ID are uniquely scoped within windows , tree nodes , etc . so no conflict can happen if you have two buttons called " OK "
in two different windows or in two different locations of a tree .
@ -413,34 +410,35 @@
- If you have a same ID twice in the same location , you ' ll have a conflict :
Button ( " OK " ) ;
Button ( " OK " ) ; // ID collision! Both buttons will be treated as the same.
Button ( " OK " ) ; // ID collision! Both buttons will be treated as the same.
Fear not ! this is easy to solve and there are many ways to solve it !
- When passing a label you can optionally specify extra unique ID information within string itself .
This helps solving the simpler collision cases . Use " ## " to pass a complement to the ID that won ' t be visible to the end - user :
Use " ## " to pass a complement to the ID that won ' t be visible to the end - user .
This helps solving the simple collision cases when you know which items are going to be created .
Button ( " Play " ) ; // Label = "Play", ID = hash of "Play"
Button ( " Play##foo1 " ) ; // Label = "Play", ID = hash of "Play##foo1" (different from above)
Button ( " Play##foo2 " ) ; // Label = "Play", ID = hash of "Play##foo2" (different from above)
Button ( " Play " ) ; // Label = "Play", ID = hash of "Play"
Button ( " Play##foo1 " ) ; // Label = "Play", ID = hash of "Play##foo1" (different from above)
Button ( " Play##foo2 " ) ; // Label = "Play", ID = hash of "Play##foo2" (different from above)
- If you want to completely hide the label , but still need an ID :
Checkbox ( " ##On " , & b ) ; // Label = "", ID = hash of "##On" (no label!)
Checkbox ( " ##On " , & b ) ; // Label = "", ID = hash of "##On" (no label!)
- Occasionally / rarely you might want change a label while preserving a constant ID . This allows you to animate labels .
For example you may want to include varying information in a window title bar ( and windows are uniquely identified by their ID . . obviously )
For example you may want to include varying information in a window title bar , but windows are uniquely identified by their ID . .
Use " ### " to pass a label that isn ' t part of ID :
Button ( " Hello###ID " ; // Label = "Hello", ID = hash of "ID"
Button ( " World###ID " ; // Label = "World", ID = hash of "ID" (same as above)
sprintf ( buf , " My game (%f FPS)###MyGame " ;
sprintf ( buf , " My game (%f FPS)###MyGame " , fps );
Begin ( buf ) ; // Variable label, ID = hash of "MyGame"
- Use PushID ( ) / PopID ( ) to create scopes and avoid ID conflicts within the same Window .
This is the most convenient way of distinguishing ID if you are iterating and creating many UI elements .
You can push a pointer , a string or an integer value . Remember that ID are formed from the concatenation of in the ID stack !
You can push a pointer , a string or an integer value . Remember that ID are formed from the concatenation of _ everything_ in the ID stack !
for ( int i = 0 ; i < 100 ; i + + )
{
@ -570,16 +568,25 @@
so you don ' t rely on the default globals .
Q : How can I use the drawing facilities without an ImGui window ? ( using ImDrawList API )
A : The easiest way is to create a dummy window . Call Begin ( ) with NoTitleBar | NoResize | NoMove | NoScrollbar | NoSavedSettings | NoInputs flag ,
zero background alpha , then retrieve the ImDrawList * via GetWindowDrawList ( ) and draw to it in any way you like .
You can also perfectly create a standalone ImDrawList instance _but_ you need ImGui to be initialized because ImDrawList pulls from ImGui
data to retrieve the coordinates of the white pixel .
A : - You can create a dummy window . Call Begin ( ) with NoTitleBar | NoResize | NoMove | NoScrollbar | NoSavedSettings | NoInputs flag ,
push a ImGuiCol_WindowBg with zero alpha , then retrieve the ImDrawList * via GetWindowDrawList ( ) and draw to it in any way you like .
- You can call ImGui : : GetOverlayDrawList ( ) and use this draw list to display contents over every other imgui windows .
- You can create your own ImDrawList instance . You ' ll need to initialize them ImGui : : GetDrawListSharedData ( ) , or create your own ImDrawListSharedData .
Q : I integrated Dear ImGui in my engine and the text or lines are blurry . .
A : In your Render function , try translating your projection matrix by ( 0.5f , 0.5f ) or ( 0.375f , 0.375f ) .
Also make sure your orthographic projection matrix and io . DisplaySize matches your actual framebuffer dimension .
Q : I integrated Dear ImGui in my engine and some elements are clipping or disappearing when I move windows around . .
A : You are probably mishandling the clipping rectangles in your render function .
Rectangles provided by ImGui are defined as ( x1 = left , y1 = top , x2 = right , y2 = bottom ) and NOT as ( x1 , y1 , width , height ) .
- tip : you can call Begin ( ) multiple times with the same name during the same frame , it will keep appending to the same window .
this is also useful to set yourself in the context of another window ( to get / set other settings )
this is also useful to set yourself in the context of another window ( to get / set other settings )
- tip : you can create widgets without a Begin ( ) / End ( ) block , they will go in an implicit window called " Debug " .
- tip : the ImGuiOnceUponAFrame helper will allow run the block of code only once a frame . You can use it to quickly add custom UI in the middle
of a deep nested inner loop in your code .
of a deep nested inner loop in your code .
- tip : you can call Render ( ) multiple times ( e . g for VR renders ) .
- tip : call and read the ShowDemoWindow ( ) code in imgui_demo . cpp for more example of how to use ImGui !
@ -3914,6 +3921,7 @@ bool ImGui::BeginPopupModal(const char* name, bool* p_open, ImGuiWindowFlags fla
}
// Center modal windows by default
// FIXME: Should test for (PosCond & window->SetWindowPosAllowFlags) with the upcoming window.
if ( g . NextWindowData . PosCond = = 0 )
SetNextWindowPos ( g . IO . DisplaySize * 0.5f , ImGuiCond_Appearing , ImVec2 ( 0.5f , 0.5f ) ) ;
omar
7 years ago