I used the forge bus and now it works, thanks a lot.
If somebody needs it:
@Mod.EventBusSubscriber(modid = MYMOD.MOD_ID, bus = Mod.EventBusSubscriber.Bus.FORGE, value = Dist.CLIENT)
public class CustomEvents implements IModBusEvent {
static Minecraft mc = Minecraft.getInstance();
private static final ResourceLocation IMG_LOCATION = new ResourceLocation(MYMOD.MOD_ID,"textures/scream/img.png");
protected static int screenWidth;
protected static int screenHeight;
@SubscribeEvent
public static void RenderEvent(RenderGameOverlayEvent.Post event) {
Player player = Minecraft.getInstance().player;
//Options settings = Minecraft.getInstance().options;
screenWidth = mc.getWindow().getGuiScaledWidth();
screenHeight = mc.getWindow().getGuiScaledHeight();
assert player != null;
if (player.hasEffect(MobEffects.GLOWING)) {
RenderSystem.disableDepthTest();
RenderSystem.depthMask(false);
RenderSystem.defaultBlendFunc();
RenderSystem.setShader(GameRenderer::getPositionTexShader);
RenderSystem.setShaderColor(1.0F, 1.0F, 1.0F, 1F);
RenderSystem.setShaderTexture(0, IMG_LOCATION);
Tesselator tesselator = Tesselator.getInstance();
BufferBuilder bufferbuilder = tesselator.getBuilder();
bufferbuilder.begin(VertexFormat.Mode.QUADS, DefaultVertexFormat.POSITION_TEX);
bufferbuilder.vertex(0.0D, screenHeight, -90.0D).uv(0.0F, 1.0F).endVertex();
bufferbuilder.vertex(screenWidth, (double) screenHeight, -90.0D).uv(1.0F, 1.0F).endVertex();
bufferbuilder.vertex(screenWidth, 0.0D, -90.0D).uv(1.0F, 0.0F).endVertex();
bufferbuilder.vertex(0.0D, 0.0D, -90.0D).uv(0.0F, 0.0F).endVertex();
tesselator.end();
RenderSystem.depthMask(true);
RenderSystem.enableDepthTest();
RenderSystem.setShaderColor(0.0F, 0.0F, 1.0F, 1.0F);
}
}}