将骨骼数据发送到glsl着色器

时间:2013-09-07 04:36:01

标签: c++ opengl

好的,所以我可以加载一个带有顶点,纹理坐标和法线的基本模型,并且可以毫无问题地渲染它。

然而,当我尝试投入一些骨骼信息时,当我尝试在着色器中操作骨骼数据时,骨骼数据似乎已经损坏(或其他什么?)。

这是我将数据加载和渲染到opengl的代码(设置着色器并发送视图矩阵,世界矩阵等在另一个类中完成):

/*
 * Mesh.cpp
 *
 *  Created on: 2011-05-08
 *      Author: jarrett
 */

#include <boost/log/trivial.hpp>

#include "../common/utilities/AssImpUtilities.h"

#include "Mesh.h"

namespace glr {
namespace glw {
Mesh::Mesh(IOpenGlDevice* openGlDevice,
        const std::string path, 
        std::vector< glm::vec3 > vertices, 
        std::vector< glm::vec3 > normals,
        std::vector< glm::vec2 > textureCoordinates,
        std::vector< glm::vec4 > colors,
        std::vector<VertexBoneData > bones,
        BoneData boneData)
    : openGlDevice_(openGlDevice), vertices_(vertices), normals_(normals), textureCoordinates_(textureCoordinates), colors_(colors), bones_(bones), boneData_(boneData)
{
    BOOST_LOG_TRIVIAL(debug) << "loading mesh into video memory...";

    // create our vao
    glGenVertexArrays(1, &vaoId_);
    glBindVertexArray(vaoId_);

    // create our vbos
    glGenBuffers(5, &vboIds_[0]);

    glBindBuffer(GL_ARRAY_BUFFER, vboIds_[0]);
    glBufferData(GL_ARRAY_BUFFER, vertices_.size() * sizeof(glm::vec3), &vertices_[0], GL_STATIC_DRAW);
    glEnableVertexAttribArray(0);
    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 0, 0);

    glBindBuffer(GL_ARRAY_BUFFER, vboIds_[1]);
    glBufferData(GL_ARRAY_BUFFER, textureCoordinates_.size() * sizeof(glm::vec2), &textureCoordinates_[0], GL_STATIC_DRAW);
    glEnableVertexAttribArray(1);
    glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 0, 0);

    glBindBuffer(GL_ARRAY_BUFFER, vboIds_[2]);
    glBufferData(GL_ARRAY_BUFFER, normals_.size() * sizeof(glm::vec3), &normals_[0], GL_STATIC_DRAW);
    glEnableVertexAttribArray(2);
    glVertexAttribPointer(2, 3, GL_FLOAT, GL_FALSE, 0, 0);

    std::cout << "SIZE: " << vertices_.size() << " " << sizeof(glm::ivec4) << " " << bones_.size() << " " << sizeof(VertexBoneData) << std::endl;

    // Convert data into simple vectors, then send to OpenGL
    std::vector< glm::ivec4 > boneIds = std::vector< glm::ivec4 >();
    std::vector< glm::vec4 > weights = std::vector< glm::vec4 >();

    for ( VertexBoneData& d : bones_ )
    {
        boneIds.push_back( d.boneIds );
        weights.push_back( d.weights );
    }

    glBindBuffer(GL_ARRAY_BUFFER, vboIds_[3]);
    glBufferData(GL_ARRAY_BUFFER, boneIds.size() * sizeof(glm::ivec4), &boneIds[0], GL_STATIC_DRAW);
    glEnableVertexAttribArray(3);
    glVertexAttribPointer(3, 4, GL_INT, GL_FALSE, 0, 0);

    glBindBuffer(GL_ARRAY_BUFFER, vboIds_[4]);
    glBufferData(GL_ARRAY_BUFFER, weights.size() * sizeof(glm::vec4), &weights[0], GL_STATIC_DRAW);
    glEnableVertexAttribArray(4);
    glVertexAttribPointer(4, 4, GL_FLOAT, GL_FALSE, 0, 0);

    // Disable our Vertex Array Object
    //glEnableVertexAttribArray(0);
    // Disable our Vertex Buffer Object
    glBindVertexArray(0);

    GlError err = openGlDevice_->getGlError();
    if (err.type != GL_NONE)
    {
        // TODO: throw error
        BOOST_LOG_TRIVIAL(error) << "Error loading mesh in opengl";
        BOOST_LOG_TRIVIAL(error) << "OpenGL error: " << err.name;
    }
    else
    {
        BOOST_LOG_TRIVIAL(debug) << "Successfully loaded mesh.";
    }
}

Mesh::~Mesh()
{
}

void Mesh::render()
{
    glBindVertexArray(vaoId_);

    glDrawArrays(GL_TRIANGLES, 0, vertices_.size());

    glBindVertexArray(0);
}

BoneData& Mesh::getBoneData()
{
    return boneData_;
}
}
}

我的实际着色器是:

#version 150 core

struct Light {
    vec4 ambient;
    vec4 diffuse;
    vec4 specular;
    vec4 position;
    vec4 direction;
};


in vec3 in_Position;
in vec2 in_Texture;
in vec3 in_Normal;
in ivec4 in_BoneIds;
in vec4 in_BoneWeights;

out vec2 textureCoord;
out vec3 normalDirection;
out vec3 lightDirection;
out float bug;

layout(std140) uniform Lights 
{
    Light lights[ 1 ];
};

void main() {        
    gl_Position = pvmMatrix * vec4(in_Position, 1.0);

    vec4 lightDirTemp = viewMatrix * lights[0].direction;

    textureCoord = in_Texture;

    //vec4 normalDirTemp = boneTransform * vec4(in_Normal, 1.0);
    //normalDirection = normalize(normalMatrix * normalDirTemp.xyz);
    normalDirection = normalize(normalMatrix * in_Normal);

    lightDirection = normalize(vec3(lightDirTemp));



    // If we have any bugs, should highlight the vertex red or green
    bug = 0.0;
    float sum = in_BoneWeights[0] + in_BoneWeights[1] + in_BoneWeights[2] + in_BoneWeights[3];
    if (sum > 1.5f)
        bug = 1.0;
    else if (sum < 0.95f)
        bug = 2.0;
    // disable bug highlighting
    //bug = 0.0;        
}

如果bug = 1.0,则顶点为红色,如果为but = 2.0,则顶点为绿色。我看到所有顶点现在都是红色的,这意味着sum大于1.5f

我已经确认每组权重的总和实际上是<= 1.0f ...那么在世界中如何在着色器中不是这种情况呢?

有人看到我遗失的任何明显事物吗?

编辑:看起来我发现了问题 - 我没有在我的glBindAttribLocation个变量上调用in - 添加后:

glBindAttribLocation(programId_, 0, "in_Position");
    glBindAttribLocation(programId_, 1, "in_Texture");
    glBindAttribLocation(programId_, 2, "in_Color");
    glBindAttribLocation(programId_, 3, "in_BoneIds");
    glBindAttribLocation(programId_, 4, "in_BoneWeights");

到我的着色器加载代码,它工作正常。奇怪的是 - 我没有必要为前3(位置,纹理和颜色)这样做,它工作得很好。但是当我添加骨骼信息时,我突然需要这个......为什么?

1 个答案:

答案 0 :(得分:3)

您需要使用glVertexAttribIPointer (...)ivec<N>顶点属性提供数据。如果您认为在设置属性位置之前遇到“损坏”,请等到您在着色器中编写实际需要骨骼ID的代码...这些值将毫无意义,因为您使用了错误的API调用来关联属性具有特定绑定位置的数据。

glVertexAttribPointer (...)变体在获取GL_INT数据类型时没有遇到任何问题,但它会将其转换为浮点数(并且它可以在过程中规范化定点值,因此额外参数)。因此,此变体应该将数据提供给vec<N>顶点属性,而不是ivec<N>

更简洁地说,对整数顶点属性使用glVertexAttribIPointer,对浮点使用glVertexAttribPointer