[SOLVED] Problems with imgui

Troubleshooting gui
1 
/*
 * Click nbfs://nbhost/SystemFileSystem/Templates/Licenses/license-default.txt to change this license
 * Click nbfs://nbhost/SystemFileSystem/Templates/Classes/Class.java to edit this template
 */
package jmeimgui;

import static com.jme3.renderer.opengl.GL.GL_LINEAR;
import static com.jme3.renderer.opengl.GL.GL_RGBA;
import static com.jme3.renderer.opengl.GL.GL_TEXTURE_2D;
import static com.jme3.renderer.opengl.GL.GL_TEXTURE_MAG_FILTER;
import static com.jme3.renderer.opengl.GL.GL_TEXTURE_MIN_FILTER;
import static com.jme3.renderer.opengl.GL.GL_UNSIGNED_BYTE;
import com.jme3.system.JmeContext;
import com.jme3.system.JmeSystem;
import com.jme3.system.Platform;
import com.jme3.system.lwjgl.LwjglWindow;
import imgui.ImFont;
import imgui.ImFontConfig;
import imgui.ImFontGlyphRangesBuilder;
import imgui.ImGui;
import imgui.ImGuiIO;
import imgui.flag.ImGuiConfigFlags;
import imgui.gl3.ImGuiImplGl3;
import imgui.glfw.ImGuiImplGlfw;
import imgui.type.ImInt;
import java.io.IOException;
import java.net.URISyntaxException;
import java.nio.ByteBuffer;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.Objects;
import org.lwjgl.glfw.GLFW;
import static org.lwjgl.opengl.GL11.GL_TEXTURE_BINDING_2D;
import static org.lwjgl.opengl.GL11.glGenTextures;
import static org.lwjgl.opengl.GL11.glTexImage2D;
import static org.lwjgl.opengl.GL11.glTexParameteri;
import static org.lwjgl.opengl.GL11C.glBindTexture;
import static org.lwjgl.opengl.GL11C.glGetInteger;

/**
 *
 * @author Icyboxs
 */
public class JmeImGui {
    
    
    private final ImGuiImplGlfw imGuiGlfw = new ImGuiImplGlfw();
    private final ImGuiImplGl3 imGuiGl3 = new ImGuiImplGl3();
    private long windowHandle;
        /**
     * Method called at the beginning of the main cycle.
     * It starts a new ImGui frame.
     */
    public void startFrame() {
        imGuiGlfw.newFrame();
        ImGui.newFrame();
    }

    /**
     * Method called in the end of the main cycle.
     * It renders ImGui to prepare an updated frame.
     */
    public void endFrame() {
        ImGui.render();
        imGuiGl3.renderDrawData(ImGui.getDrawData());

        if (ImGui.getIO().hasConfigFlags(ImGuiConfigFlags.ViewportsEnable)) {
            final long backupWindowPtr = GLFW.glfwGetCurrentContext();
            ImGui.updatePlatformWindows();
            ImGui.renderPlatformWindowsDefault();
            GLFW.glfwMakeContextCurrent(backupWindowPtr);
        }

    }
    /**
     * Method to dispose all used ImGui resources.
     */
    public void dispose() {
        imGuiGl3.dispose();
        imGuiGlfw.dispose();
        ImGui.destroyContext();
    }
    
    public void init(JmeContext context, Runnable beforeInit) {
        windowHandle = ((LwjglWindow)context).getWindowHandle();
        ImGui.createContext();
        if (beforeInit != null) beforeInit.run();
        imGuiGlfw.init(windowHandle, true);
        imGuiGl3.init(decideGlslVersion());
    }
    
    public void init(JmeContext context) {
        init(context, null);
    }
    

    
      protected String decideGlslVersion() {
        return JmeSystem.getPlatform().getOs() == Platform.Os.MacOS ? "#version 150" : "#version 130";
    }
      
    public void refreshFontTexture() {
        ImInt fontW = new ImInt();
        ImInt fontH = new ImInt();
        ImGuiIO imGuiIO = ImGui.getIO();
        ByteBuffer fontData = imGuiIO.getFonts().getTexDataAsRGBA32(fontW, fontH);
        int originalTexture = glGetInteger(GL_TEXTURE_BINDING_2D);
        int fontTexture = glGenTextures();
        glBindTexture(GL_TEXTURE_2D, fontTexture);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, fontW.get(), fontH.get(), 0, GL_RGBA, GL_UNSIGNED_BYTE, fontData);
        imGuiIO.getFonts().setTexID(fontTexture);
        glBindTexture(GL_TEXTURE_2D, originalTexture);
    }
}

I use this code to initialize imgui

I don’t know why I can only initialize in class Main extends SimpleApplication

If I initialize in the class extends BaseAppState then imgui is not visible on the screen and no error is generated.

Writing an imgui window in simpleRender

    @Override
    public void simpleRender(RenderManager rm) {

        jmeimGui.startFrame();
        if (ImGui.begin("你好")) {
            if (ImGui.beginMenuBar()) {
            }
            if (ImGui.sliderFloat("X", imGuidata.getLocationX(), -1000f, 1000f)) {
            }
            if (ImGui.sliderFloat("Y", imGuidata.getLocationY(), -1000f, 1000f)) {
            }
            if (ImGui.sliderFloat("Z", imGuidata.getLocationZ(), -1000, 1000f)) {
            }
        }
        ImGui.end();
        jmeimGui.endFrame();

    }

Writing an imgui window in render

    @Override
    public void render(RenderManager rm) {


    UIjmeimGui.startFrame();

  
    if (ImGui.begin("Test Window")) {
        ImGui.text("Hello, ImGui!");
        if (ImGui.button("Click Me")) {
            System.out.println("Button clicked!");
        }
    }
    ImGui.end();

 
    UIjmeimGui.endFrame();
    }

The imgui written in the render in extends BaseAppState will not be displayed in the screen.

2

what does the opengl profiler say?
you don’t show where you are actually initializing the imgui.

1 Like
3

I found the problem.

startFrame();


endFrame();

startFrame(); and endFrame(); can only occur once per frame cycle of jme

/*
 * Click nbfs://nbhost/SystemFileSystem/Templates/Licenses/license-default.txt to change this license
 * Click nbfs://nbhost/SystemFileSystem/Templates/Classes/Interface.java to edit this template
 */
package GUI.imgui;

/**
 *
 * @author icyboxs
 */
public interface imguiComponent {
    void execute();
    public String getComponentName();
}


/*
 * Click nbfs://nbhost/SystemFileSystem/Templates/Licenses/license-default.txt to change this license
 * Click nbfs://nbhost/SystemFileSystem/Templates/Classes/Class.java to edit this template
 */
package GUI.imgui;

import java.util.HashMap;
import java.util.Map;

/**
 *
 * @author icyboxs
 */
public class ComponentRegistrar {
    private final Map<String, imguiComponent> componentMap = new HashMap<>();
    
    // 私有构造方法实现单例
    private ComponentRegistrar() {}
    
    private static class Holder {
        private static final ComponentRegistrar INSTANCE = new ComponentRegistrar();
    }
    
    public static ComponentRegistrar getInstance() {
        return Holder.INSTANCE;
    }
    
    public void register(imguiComponent component) {
        componentMap.put(component.getComponentName(), component);
    }
    
    public imguiComponent getComponent(String name) {
        return componentMap.get(name);
    }
    
    public void executeAll() {
        componentMap.values().forEach(imguiComponent::execute);
    }
}

Run the contents of the imgui in main using component registration
So, my problem is solved. I hope this helps someone else.

2 Likes