Evening all,

 

Trying my first mod here,  I've got some code that renders a highlight around air blocks.

 

The code works perfectly, until we come across snow covered blocks,  Then it crashes the client with little to no information as to why.  Here is the code, and the error below. (the try catch is just for debugging)

try
        {
            EntityPlayerSP player = Minecraft.getMinecraft().player;
            World world = player.getEntityWorld();

            if (player.getHeldItemMainhand().getItem() == StrapItems.BASIC_STRAP)
            {
                ItemBasicStrap myItem = (ItemBasicStrap) player.getHeldItemMainhand().getItem();
                RayTraceResult tracer = player.rayTrace(myItem.BlockRange, 1.0F);

                BlockPos pos = tracer.getBlockPos();

                GlStateManager.enableBlend();
                GlStateManager.tryBlendFuncSeparate(GlStateManager.SourceFactor.SRC_ALPHA, GlStateManager.DestFactor.ONE_MINUS_SRC_ALPHA, GlStateManager.SourceFactor.ONE, GlStateManager.DestFactor.ZERO);
                GlStateManager.glLineWidth(3.0F);
                GlStateManager.disableTexture2D();
                GlStateManager.depthMask(false);

                Block state = world.getBlockState(pos).getBlock();

                double x = player.lastTickPosX + (player.posX - player.lastTickPosX) * event.getPartialTicks();
                double y = player.lastTickPosY + (player.posY - player.lastTickPosY) * event.getPartialTicks();
                double z = player.lastTickPosZ + (player.posZ - player.lastTickPosZ) * event.getPartialTicks();

                RenderGlobal.drawSelectionBoundingBox(state.FULL_BLOCK_AABB.offset(-x, -y, -z).offset(pos).grow(0.002), 1.0F, 1.0F, 1.0F, 0.4F);

                GlStateManager.depthMask(true);
                GlStateManager.enableTexture2D();
                GlStateManager.disableBlend();
            }
        }
        catch (Exception ex)
        {
            logger.info("AIR STRAPS AIR STRAPS AIR STRAPS >> {}", ex.getMessage());
        }

 

Error

Quote

[20:50:43] [main/ERROR] [FML]: Exception caught during firing event net.minecraftforge.client.event.RenderWorldLastEvent@492f3239:
java.lang.NullPointerException: null
    at com.daten.AirStraps.world.renderHighlights.onRender(renderHighlights.java:60) ~[renderHighlights.class:?]
    at net.minecraftforge.fml.common.eventhandler.ASMEventHandler_6_renderHighlights_onRender_RenderWorldLastEvent.invoke(.dynamic) ~[?:?]
    at net.minecraftforge.fml.common.eventhandler.ASMEventHandler.invoke(ASMEventHandler.java:90) ~[ASMEventHandler.class:?]
    at net.minecraftforge.fml.common.eventhandler.EventBus.post(EventBus.java:182) [EventBus.class:?]
    at net.minecraftforge.client.ForgeHooksClient.dispatchRenderLast(ForgeHooksClient.java:181) [ForgeHooksClient.class:?]
    at net.minecraft.client.renderer.EntityRenderer.renderWorldPass(EntityRenderer.java:1485) [EntityRenderer.class:?]
    at net.minecraft.client.renderer.EntityRenderer.renderWorld(EntityRenderer.java:1312) [EntityRenderer.class:?]
    at net.minecraft.client.renderer.EntityRenderer.updateCameraAndRender(EntityRenderer.java:1115) [EntityRenderer.class:?]
    at net.minecraft.client.Minecraft.runGameLoop(Minecraft.java:1208) [Minecraft.class:?]
    at net.minecraft.client.Minecraft.run(Minecraft.java:441) [Minecraft.class:?]
    at net.minecraft.client.main.Main.main(Main.java:118) [Main.class:?]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_201]
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[?:1.8.0_201]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_201]
    at java.lang.reflect.Method.invoke(Method.java:498) ~[?:1.8.0_201]
    at net.minecraft.launchwrapper.Launch.launch(Launch.java:135) [launchwrapper-1.12.jar:?]
    at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.12.jar:?]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_201]
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[?:1.8.0_201]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_201]
    at java.lang.reflect.Method.invoke(Method.java:498) ~[?:1.8.0_201]
    at net.minecraftforge.gradle.GradleStartCommon.launch(GradleStartCommon.java:97) [start/:?]
    at GradleStart.main(GradleStart.java:25) [start/:?]
[20:50:43] [main/ERROR] [FML]: Index: 1 Listeners:
[20:50:43] [main/ERROR] [FML]: 0: NORMAL
[20:50:43] [main/ERROR] [FML]: 1: ASM: class com.daten.AirStraps.world.renderHighlights onRender(Lnet/minecraftforge/client/event/RenderWorldLastEvent;)V
[20:50:43] [Client Shutdown Thread/INFO] [minecraft/MinecraftServer]: Stopping server
[20:50:43] [Client Shutdown Thread/INFO] [minecraft/MinecraftServer]: Saving players
AL lib: (EE) alc_cleanup: 1 device not closed

 

Any help would be greatly appreciated!!

 

Edited February 17, 20196 yr by DatenThielt
Update Title

12 hours ago, diesieben07 said:

Little to no information? It tells you exactly what's wrong and on what line. Use the debugger to figure out which value is null and then fix your bug.

That's what I get for programming after a few beers.    Thanks for the reality slap.  The try-catch was hiding the original error line, turned out the raytrace could return null over certain blocks.  Fixed and thank you!