path: root/src/main/java/at/hannibal2/skyhanni/utils/EntityOutlineRenderer.kt

package at.hannibal2.skyhanni.utils

import at.hannibal2.skyhanni.SkyHanniMod
import at.hannibal2.skyhanni.config.enums.OutsideSbFeature
import at.hannibal2.skyhanni.events.LorenzTickEvent
import at.hannibal2.skyhanni.events.RenderEntityOutlineEvent
import at.hannibal2.skyhanni.mixins.transformers.CustomRenderGlobal
import at.hannibal2.skyhanni.test.command.ErrorManager
import net.minecraft.client.Minecraft
import net.minecraft.client.renderer.GlStateManager
import net.minecraft.client.renderer.OpenGlHelper
import net.minecraft.client.renderer.RenderHelper
import net.minecraft.client.renderer.culling.ICamera
import net.minecraft.client.shader.Framebuffer
import net.minecraft.entity.Entity
import net.minecraft.entity.EntityLivingBase
import net.minecraft.util.BlockPos
import net.minecraftforge.client.MinecraftForgeClient
import net.minecraftforge.fml.common.eventhandler.EventPriority
import net.minecraftforge.fml.common.eventhandler.SubscribeEvent
import org.lwjgl.opengl.GL11
import org.lwjgl.opengl.GL13
import org.lwjgl.opengl.GL30
import java.lang.reflect.InvocationTargetException
import java.lang.reflect.Method

/**
 * Class to handle all entity outlining, including xray and no-xray rendering
 * Features that include entity outlining should subscribe to the {@link RenderEntityOutlineEvent}.
 *
 * Credit to SkyblockAddons and Biscuit Development
 * https://github.com/BiscuitDevelopment/SkyblockAddons/blob/main/src/main/java/codes/biscuit/skyblockaddons/features/EntityOutlines/EntityOutlineRenderer.java
 *
 */
object EntityOutlineRenderer {

    private val entityRenderCache: CachedInfo = CachedInfo(null, null, null)
    private var stopLookingForOptifine = false
    private var isMissingMixin = false
    private var isFastRender: Method? = null
    private var isShaders: Method? = null
    private var isAntialiasing: Method? = null
    private var emptyLastTick = false
    private val swapBuffer by lazy { initSwapBuffer() }
    private val logger = LorenzLogger("entity_outline_renderer")
    private val mc get() = Minecraft.getMinecraft()
    private val BUF_FLOAT_4: java.nio.FloatBuffer = org.lwjgl.BufferUtils.createFloatBuffer(4)

    private val CustomRenderGlobal.frameBuffer get() = entityOutlineFramebuffer_skyhanni
    private val CustomRenderGlobal.shader get() = entityOutlineShader_skyhanni

    /**
     * @return a new framebuffer with the size of the main framebuffer
     */
    private fun initSwapBuffer(): Framebuffer {
        val main = mc.framebuffer
        val framebuffer = Framebuffer(main.framebufferTextureWidth, main.framebufferTextureHeight, true)
        framebuffer.setFramebufferFilter(GL11.GL_NEAREST)
        framebuffer.setFramebufferColor(0.0f, 0.0f, 0.0f, 0.0f)
        return framebuffer
    }

    private fun updateFramebufferSize() {
        val width = mc.displayWidth
        val height = mc.displayHeight
        if (swapBuffer.framebufferWidth != width || swapBuffer.framebufferHeight != height) {
            swapBuffer.createBindFramebuffer(width, height)
        }
        val renderGlobal = mc.renderGlobal as CustomRenderGlobal
        val outlineBuffer = renderGlobal.frameBuffer
        if (outlineBuffer.framebufferWidth != width || outlineBuffer.framebufferHeight != height) {
            outlineBuffer.createBindFramebuffer(width, height)
            renderGlobal.shader.createBindFramebuffers(width, height)
        }
    }

    /**
     * Renders xray and no-xray entity outlines.
     *
     * @param camera       the current camera
     * @param partialTicks the progress to the next tick
     * @param vector       the camera position as Vector
     */
    @JvmStatic
    fun renderEntityOutlines(camera: ICamera, partialTicks: Float, vector: LorenzVec): Boolean {
        val shouldRenderOutlines = shouldRenderEntityOutlines()

        if (!(shouldRenderOutlines && !isCacheEmpty() && MinecraftForgeClient.getRenderPass() == 0)) {
            return !shouldRenderOutlines
        }

        val renderGlobal = mc.renderGlobal as CustomRenderGlobal
        val renderManager = mc.renderManager
        mc.theWorld.theProfiler.endStartSection("entityOutlines")
        updateFramebufferSize()

        // Clear and bind the outline framebuffer
        renderGlobal.frameBuffer.framebufferClear()
        renderGlobal.frameBuffer.bindFramebuffer(false)

        // Vanilla options
        RenderHelper.disableStandardItemLighting()
        GlStateManager.disableFog()
        mc.renderManager.setRenderOutlines(true)

        // Enable outline mode
        GL11.glTexEnvi(GL11.GL_TEXTURE_ENV, GL11.GL_TEXTURE_ENV_MODE, GL13.GL_COMBINE)
        GL11.glTexEnvi(GL11.GL_TEXTURE_ENV, GL13.GL_COMBINE_RGB, GL11.GL_REPLACE)
        GL11.glTexEnvi(GL11.GL_TEXTURE_ENV, GL13.GL_SOURCE0_RGB, GL13.GL_CONSTANT)
        GL11.glTexEnvi(GL11.GL_TEXTURE_ENV, GL13.GL_OPERAND0_RGB, GL11.GL_SRC_COLOR)
        GL11.glTexEnvi(GL11.GL_TEXTURE_ENV, GL13.GL_COMBINE_ALPHA, GL11.GL_REPLACE)
        GL11.glTexEnvi(GL11.GL_TEXTURE_ENV, GL13.GL_SOURCE0_ALPHA, GL11.GL_TEXTURE)
        GL11.glTexEnvi(GL11.GL_TEXTURE_ENV, GL13.GL_OPERAND0_ALPHA, GL11.GL_SRC_ALPHA)

        // Render x-ray outlines first, ignoring the depth buffer bit
        if (!isXrayCacheEmpty()) {
            // Xray is enabled by disabling depth testing
            GlStateManager.depthFunc(GL11.GL_ALWAYS)

            entityRenderCache.xrayCache?.forEach { (key, value) ->
                // Test if the entity should render, given the player's camera position
                if (!shouldRender(camera, key, vector)) return@forEach

                try {
                    if (key !is EntityLivingBase) outlineColor(value)
                    renderManager.renderEntityStatic(key, partialTicks, true)
                } catch (ignored: Exception) {
                }
            }

            // Reset depth function
            GlStateManager.depthFunc(GL11.GL_LEQUAL)
        }

        // Render no-xray outlines second, taking into consideration the depth bit
        if (!isNoXrayCacheEmpty()) {
            if (!isNoOutlineCacheEmpty()) {
                // Render other entities + terrain that may occlude an entity outline into a depth buffer
                swapBuffer.framebufferClear()
                copyBuffers(mc.framebuffer, swapBuffer, GL11.GL_DEPTH_BUFFER_BIT)
                swapBuffer.bindFramebuffer(false)

                // Copy terrain + other entities depth into outline frame buffer to now switch to no-xray outlines
                entityRenderCache.noOutlineCache?.forEach { entity ->
                    // Test if the entity should render, given the player's instantaneous camera position
                    if (!shouldRender(camera, entity, vector)) return@forEach

                    try {
                        renderManager.renderEntityStatic(entity, partialTicks, true)
                    } catch (ignored: Exception) {
                    }
                }

                // Copy the entire depth buffer of everything that might occlude outline to outline framebuffer
                copyBuffers(swapBuffer, renderGlobal.frameBuffer, GL11.GL_DEPTH_BUFFER_BIT)
                renderGlobal.frameBuffer.bindFramebuffer(false)
            } else {
                copyBuffers(mc.framebuffer, renderGlobal.frameBuffer, GL11.GL_DEPTH_BUFFER_BIT)
            }

            // Xray disabled by re-enabling traditional depth testing
            entityRenderCache.noXrayCache?.forEach { (key, value) ->
                // Test if the entity should render, given the player's instantaneous camera position
                if (!shouldRender(camera, key, vector)) return@forEach

                try {
                    if (key !is EntityLivingBase) outlineColor(value)
                    renderManager.renderEntityStatic(key, partialTicks, true)
                } catch (ignored: Exception) {
                }
            }
        }

        // Disable outline mode
        with(GL11.GL_TEXTURE_ENV) {
            GL11.glTexEnvi(this, GL11.GL_TEXTURE_ENV_MODE, GL11.GL_MODULATE)
            GL11.glTexEnvi(this, GL13.GL_COMBINE_RGB, GL11.GL_MODULATE)
            GL11.glTexEnvi(this, GL13.GL_SOURCE0_RGB, GL11.GL_TEXTURE)
            GL11.glTexEnvi(this, GL13.GL_OPERAND0_RGB, GL11.GL_SRC_COLOR)
            GL11.glTexEnvi(this, GL13.GL_COMBINE_ALPHA, GL11.GL_MODULATE)
            GL11.glTexEnvi(this, GL13.GL_SOURCE0_ALPHA, GL11.GL_TEXTURE)
            GL11.glTexEnvi(this, GL13.GL_OPERAND0_ALPHA, GL11.GL_SRC_ALPHA)
        }

        // Vanilla options
        RenderHelper.enableStandardItemLighting()
        mc.renderManager.setRenderOutlines(false)

        // Load the outline shader
        GlStateManager.depthMask(false)
        renderGlobal.shader.loadShaderGroup(partialTicks)
        GlStateManager.depthMask(true)

        // Reset GL/framebuffers for next render layers
        GlStateManager.enableLighting()
        mc.framebuffer.bindFramebuffer(false)
        GlStateManager.enableFog()
        GlStateManager.enableBlend()
        GlStateManager.enableColorMaterial()
        GlStateManager.enableDepth()
        GlStateManager.enableAlpha()

        retur