Problems with rendering a line (1.15.2)

[thebear]

Hi, im fairly new to forge modding, so please forgive for asking such a stupid question.

Now for my problem. Im trying to draw a line between two positions. Drawing the line works, but when I change pitch or yaw, the line doesn't adjust, it just stays in the same position on screen.

I want it to adjust it's position,  just like a normal block would.

 

What happens: https://imgur.com/EwpOGuo

 

What I tried:

 

Main class:

@Mod("path")
public class path
{
    public path() {
        FMLJavaModLoadingContext.get().getModEventBus().addListener(this::setup);
    }

    private void setup(final FMLCommonSetupEvent event) {
        MinecraftForge.EVENT_BUS.register(new PathRenderer());
    }
}

 

Renderer:

public class PathRenderer {

    private Minecraft mc;

    public PathRenderer() {
        mc = Minecraft.getInstance();
    }

    @SubscribeEvent
    public void render(RenderWorldLastEvent event){

        double x = mc.player.getPositionVec().x;
        double y = mc.player.getPositionVec().y;
        double z = mc.player.getPositionVec().z;

        Vec3d p1 = new Vec3d(0, 57, 0);
        Vec3d p2 = new Vec3d(5, 57, 0);

        GL11.glPushMatrix();
        GL11.glTranslated(-x, -y, -z);
        GL11.glLineWidth(6.0f);
        GL11.glColor3ub((byte)255,(byte)0,(byte)0);
        GL11.glBegin(GL11.GL_LINES);
        GL11.glVertex3d(p1.x, p1.y, p1.z);
        GL11.glVertex3d(p2.x, p2.y, p2.z);
        GL11.glEnd();
        GL11.glPopMatrix();
    }
}

 

Edited March 14, 2020 by thebear

[DragonITA]

1 hour ago, thebear said:

Hi, im fairly new to forge modding, so please forgive for asking such a stupid question.

Now for my problem. Im trying to draw a line between two positions. Drawing the line works, but when I change pitch or yaw, the line doesn't adjust, it just stays in the same position on screen.

I want it to adjust it's position,  just like a normal block would.

 

https://imgur.com/EwpOGuo

 

What I tried:

 

Main class:

@Mod("path")
public class path
{
    public path() {
        FMLJavaModLoadingContext.get().getModEventBus().addListener(this::setup);
    }

    private void setup(final FMLCommonSetupEvent event) {
        MinecraftForge.EVENT_BUS.register(new PathRenderer());
    }
}

 

Renderer:

public class PathRenderer {

    private Minecraft mc;

    public PathRenderer() {
        mc = Minecraft.getInstance();
    }

    @SubscribeEvent
    public void render(RenderWorldLastEvent event){

        double x = mc.player.getPositionVec().x;
        double y = mc.player.getPositionVec().y;
        double z = mc.player.getPositionVec().z;

        Vec3d p1 = new Vec3d(0, 57, 0);
        Vec3d p2 = new Vec3d(5, 57, 0);

        GL11.glPushMatrix();
        GL11.glTranslated(-x, -y, -z);
        GL11.glLineWidth(6.0f);
        GL11.glColor3ub((byte)255,(byte)0,(byte)0);
        GL11.glBegin(GL11.GL_LINES);
        GL11.glVertex3d(p1.x, p1.y, p1.z);
        GL11.glVertex3d(p2.x, p2.y, p2.z);
        GL11.glEnd();
        GL11.glPopMatrix();
    }
}

 

I really not know GL11 and Java Vectors3, but i would say you that try to get the Position of a Block, then transform it into a 2D Vector, also try to get the Position on the screen (for example: if the position of your Block is (0,0,0), and your Camera perfect loo the Block, then it Position on the Screen should be: Vector2.new(Screen.X/2, Screen.Y/2)). Make the same with the other Block and use a function to write your line. I am more familiar with Lua, and in a Lua engine here was a function that was called „FindPositionOnScreen“, hope it was the same as in java, else try to write your own FindPositionOnScreen.

[thebear]

Thanks, ill try that.

[thebear]

Still can't get it to work

[Draco18s]

Maybe some old code of mine will help.

https://github.com/Draco18s/HarderStuff/blob/master/src/main/java/com/draco18s/hazards/client/HazardsClientEventHandler.java#L188

[thebear]

So I just tried the exact same code 1.14.4 and it worked perfectly. Is there something about rendering that has changed from 1.14.4 to 1.15.2?

[TheGreyGhost]

Hi

 

yes a lot has changed.  In particular, the code no longer uses the OpenGL transformation matrices, it keeps track of its own in a MatrixStack.  So you need to supply the MatrixStack to the rendering method.

 

Check out this link 

https://gist.github.com/williewillus/30d7e3f775fe93c503bddf054ef3f93e

 

And this example code (from a Tile Entity Renderer, but you should be able to adapt it.)

https://github.com/TheGreyGhost/MinecraftByExample/tree/master - see mbe21 class RenderLines or class DebugBlockVoxelShapeHighlighter

 

 

package minecraftbyexample.mbe21_tileentityrenderer;

import com.mojang.blaze3d.matrix.MatrixStack;
import com.mojang.blaze3d.vertex.IVertexBuilder;
import minecraftbyexample.usefultools.RenderTypeHelper;
import net.minecraft.client.renderer.*;
import net.minecraft.util.math.Vec3d;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

import java.awt.*;

/**
 * User: The Grey Ghost
 * Date: 12/01/2015
 * This class shows examples of rendering using lines.
 * The lines have position and colour information only  (RenderType.getLines()).  No lightmap information, which means that
 *   they will always be the same brightness regardless of day/night or nearby torches.
 */
public class RenderLines  {

  public static void renderWireframe(TileEntityMBE21 tileEntityMBE21, float partialTicks, MatrixStack matrixStack, IRenderTypeBuffer renderBuffers,
                               int combinedLight, int combinedOverlay) {
    // draw the artifact using lines
    // (Draws an inverted tetrahedron wireframe above the rendered base block (hopper block model))
    // When the TER::render method is called, the origin [0,0,0] is at the current [x,y,z] of the block being rendered.
    // The tetrahedron-drawing method draws the tetrahedron in a cube region from [0,0,0] to [1,1,1] but we want it
    //   to be in the block one above this, i.e. from [0,1,0] to [1,2,1],
    //   so we need to translate up by one block, i.e. by [0,1,0]
    final Vec3d TRANSLATION_OFFSET = new Vec3d(0, 1, 0);

    matrixStack.push(); // push the current transformation matrix + normals matrix
    matrixStack.translate(TRANSLATION_OFFSET.x,TRANSLATION_OFFSET.y,TRANSLATION_OFFSET.z); // translate
    Color artifactColour = tileEntityMBE21.getArtifactColour();

    drawTetrahedronWireframe(matrixStack, renderBuffers, artifactColour);
    matrixStack.pop(); // restore the original transformation matrix + normals matrix
  }

  /**
   * Draw an upside-down wireframe tetrahedron with its tip at [0.5,0,0.5]
   *    and 1x1 square "base" at y = 1 (x= 0 to 1, z = 0 to 1)
   * @param matrixStack transformation matrix and normal matrix
   * @param renderBuffers the renderbuffers we'll be drawing to
   */
  private static void drawTetrahedronWireframe(MatrixStack matrixStack, IRenderTypeBuffer renderBuffers,
                                               Color color) {

      final Vec3d [] BASE_VERTICES = {
              new Vec3d(0, 1, 0),
              new Vec3d(1, 1, 0),
              new Vec3d(1, 1, 1),
              new Vec3d(0, 1, 1),
      };
      final Vec3d APEX_VERTEX = new Vec3d(0.5, 0, 0.5);

    IVertexBuilder vertexBuilderLines = renderBuffers.getBuffer(RenderTypeHelper.MBE_LINE_DEPTH_WRITING_ON);
    // Note that, although RenderType.getLines() might appear to be suitable, it leads to weird rendering if used in
    // tile entity rendering, because it doesn't write to the depth buffer.  In other words, any object in the scene
    // which is drawn after the lines, will render over the top of the line (erase it) even if the object is behind
    //  the lines.  This means that RenderType.getLines() is only suitable for lines which are the last thing drawn in
    //  the scene (such as DrawBlockHighlightEvent)
    // The solution I used here is a custom RenderType for lines which does write to the depth buffer.

    Matrix4f matrixPos = matrixStack.getLast().getMatrix();  //retrieves the current transformation matrix
    // draw the base
    for (int i = 1; i < BASE_VERTICES.length; ++i) {
      drawLine(matrixPos, vertexBuilderLines, color, BASE_VERTICES[i-1], BASE_VERTICES[i]);
    }
    drawLine(matrixPos, vertexBuilderLines, color, BASE_VERTICES[BASE_VERTICES.length - 1], BASE_VERTICES[0]);

    // draw the sides (from the corners of the base to the apex)
    for (Vec3d baseVertex : BASE_VERTICES) {
      drawLine(matrixPos, vertexBuilderLines, color, APEX_VERTEX, baseVertex);
    }
  }

  /**
   * Draw a coloured line from a starting vertex to an end vertex
   * @param matrixPos the current transformation matrix
   * @param renderBuffer the vertex builder used to draw the line
   * @param startVertex
   * @param endVertex
   */
  private static void drawLine(Matrix4f matrixPos, IVertexBuilder renderBuffer,
                               Color color,
                               Vec3d startVertex, Vec3d endVertex) {
    renderBuffer.pos(matrixPos, (float) startVertex.getX(), (float) startVertex.getY(), (float) startVertex.getZ())
            .color(color.getRed(), color.getGreen(), color.getBlue(), color.getAlpha())   // there is also a version for floats (0 -> 1)
            .endVertex();
    renderBuffer.pos(matrixPos, (float) endVertex.getX(), (float) endVertex.getY(), (float) endVertex.getZ())
            .color(color.getRed(), color.getGreen(), color.getBlue(), color.getAlpha())   // there is also a version for floats (0 -> 1)
            .endVertex();
  }
}

or this one, from the HighlightBlock event

package minecraftbyexample.usefultools.debugging;

import com.mojang.blaze3d.matrix.MatrixStack;
import com.mojang.blaze3d.platform.GlStateManager;
import com.mojang.blaze3d.vertex.IVertexBuilder;
import minecraftbyexample.usefultools.RenderTypeMBE;
import net.minecraft.block.Block;
import net.minecraft.block.BlockState;
import net.minecraft.client.Minecraft;
import net.minecraft.client.renderer.*;
import net.minecraft.util.math.BlockPos;
import net.minecraft.util.math.BlockRayTraceResult;
import net.minecraft.util.math.RayTraceResult;
import net.minecraft.util.math.shapes.ISelectionContext;
import net.minecraft.util.math.shapes.VoxelShape;
import net.minecraft.world.World;
import net.minecraftforge.client.event.DrawHighlightEvent;
import net.minecraftforge.client.event.RenderTooltipEvent;
import net.minecraftforge.event.entity.living.LivingSpawnEvent;
import net.minecraftforge.eventbus.api.Event;
import net.minecraftforge.eventbus.api.SubscribeEvent;
import net.minecraftforge.fml.common.ObfuscationReflectionHelper;

import java.awt.*;
import java.lang.reflect.Field;

import static minecraftbyexample.usefultools.debugging.DebugSettings.getDebugParameter;

/**
 * Created by TGG on 27/06/2019.
 */
public class DebugBlockVoxelShapeHighlighter {
  @SubscribeEvent
  public static void onDrawBlockHighlightEvent(DrawHighlightEvent.HighlightBlock event) {
    RayTraceResult rayTraceResult = event.getTarget();
    if (rayTraceResult.getType() != RayTraceResult.Type.BLOCK) return;
    World world;

    try {
      world = getPrivateWorldFromWorldRenderer(event.getContext());
    } catch (IllegalAccessException e) {
      return;
    }

    BlockPos blockpos = ((BlockRayTraceResult) rayTraceResult).getPos();
    BlockState blockstate = world.getBlockState(blockpos);
    if (blockstate.isAir(world, blockpos) || !world.getWorldBorder().contains(blockpos)) return;

    final Color SHAPE_COLOR = Color.RED;
    final Color RENDERSHAPE_COLOR = Color.BLUE;
    final Color COLLISIONSHAPE_COLOR = Color.GREEN;
    final Color RAYTRACESHAPE_COLOR = Color.MAGENTA;

    boolean showshape = DebugSettings.getDebugParameter("showshape").isPresent();
    boolean showrendershapeshape = DebugSettings.getDebugParameter("showrendershape").isPresent();
    boolean showcollisionshape = DebugSettings.getDebugParameter("showcollisionshape").isPresent();
    boolean showraytraceshape = DebugSettings.getDebugParameter("showraytraceshape").isPresent();

    if (!(showshape || showrendershapeshape || showcollisionshape || showraytraceshape)) return;

    ActiveRenderInfo activeRenderInfo = event.getInfo();
    ISelectionContext iSelectionContext = ISelectionContext.forEntity(activeRenderInfo.getRenderViewEntity());
    IRenderTypeBuffer renderTypeBuffers = event.getBuffers();
    MatrixStack matrixStack = event.getMatrix();
    if (showshape) {
      VoxelShape shape = blockstate.getShape(world, blockpos, iSelectionContext);
      drawSelectionBox(event.getContext(), renderTypeBuffers, matrixStack, blockpos, activeRenderInfo, shape, SHAPE_COLOR);
    }
    if (showrendershapeshape) {
      VoxelShape shape = blockstate.getRenderShape(world, blockpos);
      drawSelectionBox(event.getContext(), renderTypeBuffers, matrixStack, blockpos, activeRenderInfo, shape, RENDERSHAPE_COLOR);
    }
    if (showcollisionshape) {
      VoxelShape shape = blockstate.getCollisionShape(world, blockpos, iSelectionContext);
      drawSelectionBox(event.getContext(), renderTypeBuffers, matrixStack, blockpos, activeRenderInfo, shape, COLLISIONSHAPE_COLOR);
    }
    if (showraytraceshape) {
      VoxelShape shape = blockstate.getRaytraceShape(world, blockpos);
      drawSelectionBox(event.getContext(), renderTypeBuffers, matrixStack, blockpos, activeRenderInfo, shape, RAYTRACESHAPE_COLOR);
    }
    event.setCanceled(true);
  }

  private static World getPrivateWorldFromWorldRenderer(WorldRenderer worldRenderer) throws IllegalAccessException {
    if (worldField == null) {
      worldField = ObfuscationReflectionHelper.findField(WorldRenderer.class, "world");
    }
    return (World)worldField.get(worldRenderer);
  }

  private static Field worldField;

  /**
   * copied from WorldRenderer; starting from the code marked with iprofiler.endStartSection("outline");
   *
   * @param activeRenderInfo
   */
  private static void drawSelectionBox(WorldRenderer worldRenderer, IRenderTypeBuffer renderTypeBuffers, MatrixStack matrixStack,
                                      BlockPos blockPos, ActiveRenderInfo activeRenderInfo, VoxelShape shape, Color color) {
    RenderType renderType = RenderTypeMBE.LINES();
    IVertexBuilder vertexBuilder = renderTypeBuffers.getBuffer(renderType);

    double eyeX = activeRenderInfo.getProjectedView().getX();
    double eyeY = activeRenderInfo.getProjectedView().getY();
    double eyeZ = activeRenderInfo.getProjectedView().getZ();
    final float ALPHA = 0.5f;
    drawShapeOutline(matrixStack, vertexBuilder, shape,
            blockPos.getX() - eyeX, blockPos.getY() - eyeY, blockPos.getZ() - eyeZ,
            color.getRed() / 255f, color.getGreen() / 255f, color.getBlue() / 255f, ALPHA);

  }

  private static void drawShapeOutline(MatrixStack matrixStack,
                                       IVertexBuilder vertexBuilder,
                                       VoxelShape voxelShape,
                                       double originX, double originY, double originZ,
                                       float red, float green, float blue, float alpha) {

    Matrix4f matrix4f = matrixStack.getLast().getMatrix();
    voxelShape.forEachEdge((x0, y0, z0, x1, y1, z1) -> {
      vertexBuilder.pos(matrix4f, (float)(x0 + originX), (float)(y0 + originY), (float)(z0 + originZ)).color(red, green, blue, alpha).endVertex();
      vertexBuilder.pos(matrix4f, (float)(x1 + originX), (float)(y1 + originY), (float)(z1 + originZ)).color(red, green, blue, alpha).endVertex();
    });
  }

}

 

 

Cheers

  TGG

 

Edited March 16, 2020 by TheGreyGhost

[thebear]

Thanks for your reply! Finally got it working correctly!

 

new code:

public class PathRenderer {

    private Minecraft mc;

    public PathRenderer() {
        mc = Minecraft.getInstance();
    }

    @SubscribeEvent
    public void render(RenderWorldLastEvent event){
        Tessellator tessellator = Tessellator.getInstance();
        BufferBuilder buffer = tessellator.getBuffer();
        MatrixStack matrixStack = event.getMatrixStack();
        Vec3d pos = mc.player.getPositionVec();

        matrixStack.push();
        matrixStack.translate(-pos.x, -pos.y, -pos.z);
        RenderSystem.color3f(1, 0, 0);
        RenderSystem.lineWidth(6);
        buffer.begin(GL11.GL_LINES, DefaultVertexFormats.POSITION);

        Matrix4f matrix = matrixStack.getLast().getMatrix();
        Color c = new Color(1f, 0f, 0f, 1f);

        drawLine(matrix, buffer, new Vec3d(0, 57, 0), new Vec3d(5, 57, 0));

        tessellator.draw();
        matrixStack.pop();
    }

    private void drawLine(Matrix4f matrix, BufferBuilder buffer, Vec3d p1, Vec3d p2) {
        buffer.pos(matrix, (float)p1.x + 0.5f, (float)p1.y + 0.5f, (float)p1.z + 0.5f).endVertex();
        buffer.pos(matrix, (float)p2.x + 0.5f, (float)p2.y + 0.5f, (float)p2.z + 0.5f).endVertex();
    }
}

 

[thebear]

Actually it didn't quite work in the nether, but now it does.

The reason I am posting this is, that if someone has the same problem in the future, they will find this.

I searched for this on google for a good hour, but didn't find anything.

 

New code:

 

@SubscribeEvent
    public void render(RenderWorldLastEvent event) {
        IRenderTypeBuffer.Impl buffer = Minecraft.getInstance().getRenderTypeBuffers().getBufferSource();
        IVertexBuilder builder = buffer.getBuffer(RenderType.LINES);
        MatrixStack matrixStack = event.getMatrixStack();

        PlayerEntity player = Minecraft.getInstance().player;
        double x = player.lastTickPosX + (player.getPosX() - player.lastTickPosX) * event.getPartialTicks();
        double y = player.lastTickPosY + (player.getPosY() - player.lastTickPosY) * event.getPartialTicks();
        double z = player.lastTickPosZ + (player.getPosZ() - player.lastTickPosZ) * event.getPartialTicks();

        matrixStack.push();
        matrixStack.translate(-x, -y, -z);
        Matrix4f matrix = matrixStack.getLast().getMatrix();

        builder.pos(matrix, 0, 0, 0).color(1f, 0, 0, 1f).endVertex();
        builder.pos(matrix, 0, 256, 0).color(1f, 0, 0, 1f).endVertex();

        matrixStack.pop();
        RenderSystem.disableDepthTest();
        buffer.finish(RenderType.LINES);
    }

 

[_NIMJA]

My modding workspace has just weird names like func_227860_a_() (which I think is the .push method you have) in the MatrixStack class. How did you get yours to have the right names?

 

I did some digging and found that my mappings version in my build.gradle is 20190719-1.14.3, which I assume is an old version. What is the latest version for 1.15.2?

Edited March 23, 2020 by _NIMJA

[thebear]

I actually had the same problem in the beginning too. What I did was, I downloaded the latest version from the forge website.

Make sure you download "latest", not "recommended". In the latest version, the function names should be deobfuscated.

The version I used was 1.15.2-31.1.19. Im not sure why, the mapping for it is 20200225-1.15.1.

Hope it helps you!

[Draco18s]

Note that 1.15 mappings will probably not work on 1.14