Extra2D/examples/scene_graph_demo/instanced_test.cpp

#include "instanced_test.h"
#include <assets/assets_module.h>
#include <event/events.h>
#include <module/module_registry.h>
#include <renderer/renderer_module.h>
#include <utils/logger.h>
#include <cmath>

namespace extra2d {

InstancedTestNode::InstancedTestNode() {
    setName("InstancedTest");
}

InstancedTestNode::~InstancedTestNode() {
    instanceBuffer_.shutdown();
}

bool InstancedTestNode::initialize(uint32_t instanceCount) {
    instanceCount_ = instanceCount;

    // 获取资源模块
    auto* assets = getModule<AssetsModule>();
    if (!assets) {
        E2D_LOG_ERROR("InstancedTestNode: AssetsModule not available");
        return false;
    }

    // 使用默认网格（四边形）
    mesh_ = assets->getDefaultQuad();
    if (!mesh_.isValid()) {
        E2D_LOG_ERROR("InstancedTestNode: Failed to get default quad mesh");
        return false;
    }

    // 使用默认纹理
    texture_ = assets->getDefaultTexture();

    // 获取实例化渲染材质
    material_ = assets->getInstancedMaterial();
    if (!material_.isValid()) {
        E2D_LOG_ERROR("InstancedTestNode: Failed to get instanced material");
        return false;
    }

    // 初始化实例缓冲区
    if (!instanceBuffer_.initialize(instanceCount)) {
        E2D_LOG_ERROR("InstancedTestNode: Failed to initialize instance buffer");
        return false;
    }

    // 预分配实例数据
    instanceData_.resize(instanceCount);

    // 初始化实例数据
    updateInstances();

    E2D_LOG_INFO("InstancedTestNode initialized with {} instances", instanceCount);
    return true;
}

void InstancedTestNode::update(float dt) {
    time_ += dt;

    // 更新实例变换
    updateInstances();

    // 更新GPU缓冲区
    if (!instanceData_.empty()) {
        instanceBuffer_.updateInstances(instanceData_.data(), instanceCount_);
    }
}

void InstancedTestNode::updateInstances() {
    // 创建螺旋分布的实例
    float radius = 200.0f;
    float centerX = 640.0f;
    float centerY = 360.0f;

    for (uint32_t i = 0; i < instanceCount_; ++i) {
        float t = static_cast<float>(i) / instanceCount_;
        float angle = t * 6.28318f * 3.0f + time_; // 3圈螺旋
        float r = radius * (0.2f + 0.8f * t);

        // 位置
        instanceData_[i].position.x = centerX + r * std::cos(angle);
        instanceData_[i].position.y = centerY + r * std::sin(angle);

        // 旋转（朝向中心）
        instanceData_[i].rotation = angle + 1.5708f;

        // 缩放（随距离变化）
        float scale = 0.5f + 0.5f * t;
        instanceData_[i].scale.x = scale * 32.0f;
        instanceData_[i].scale.y = scale * 32.0f;

        // 颜色（彩虹色）
        float hue = t + time_ * 0.1f;
        float r_color = std::abs(std::fmod(hue * 6.0f, 2.0f) - 1.0f);
        float g_color = std::abs(std::fmod(hue * 6.0f + 2.0f, 2.0f) - 1.0f);
        float b_color = std::abs(std::fmod(hue * 6.0f + 4.0f, 2.0f) - 1.0f);

        instanceData_[i].color.r = r_color;
        instanceData_[i].color.g = g_color;
        instanceData_[i].color.b = b_color;
        instanceData_[i].color.a = 1.0f;

        // UV坐标（使用完整纹理）
        instanceData_[i].uvX = 0.0f;
        instanceData_[i].uvY = 0.0f;
        instanceData_[i].uvWidth = 1.0f;
        instanceData_[i].uvHeight = 1.0f;
    }
}

void InstancedTestNode::render() {
    if (!isVisible() || instanceCount_ == 0) {
        return;
    }

    // 检查资源有效性
    if (!mesh_.isValid() || !material_.isValid() || !instanceBuffer_.isValid()) {
        return;
    }

    // 提交实例化渲染命令
    RenderCommand cmd;
    cmd.type = RenderCommandType::DrawMeshInstanced;
    cmd.sortKey = 0;
    cmd.drawInstanced.mesh = mesh_;
    cmd.drawInstanced.material = material_;
    cmd.drawInstanced.instanceBuffer = &instanceBuffer_;
    cmd.drawInstanced.instanceCount = instanceCount_;
    cmd.drawInstanced.instanceOffset = 0;

    events::OnRenderSubmit::emit(cmd);
}

} // namespace extra2d