如何在opengl等距场景中检测鼠标事件（来自learnopengl.com）
how to detect mouse event in opengl isometric scene (from learnopengl.com)
我正在经历 learnopengl.com 并尝试制作 3d 等距场景。
到目前为止，我已经很好地工作了。
但是 learnopengl 课程中没有的内容是如何检测 3d 中的鼠标点击 space。
我正在使用 mat4 向量的实例绘图来绘制世界的每个立方体。
接下来我想做的是点击每个立方体并修改它（现在只需更改 z 位置）。
我找到了一些关于使用 glReadPixels 的文章，但是由于我的等距投影，x 和/或 y 坐标似乎不正确。
此外，由于我使用的是实例化绘图，所以我不确定如何确定矢量中的哪个实例被单击。
我的代码在 git 中心 here。
这是主要的 class 我用来绘制立方体的：
#include "worldTile.h"
worldTile::worldTile() : drawable("instance.shader.vs", "instance.shader.fs")
{
drawType = GL_STATIC_DRAW;
baseModel = glm::mat4(1.0f);
baseModel = glm::rotate(baseModel, glm::radians(-45.0f), glm::vec3(1.0f, 0.0f, 0.0f));
baseModel = glm::rotate(baseModel, glm::radians(0.0f), glm::vec3(0.0f, 1.0f, 0.0f));
baseModel = glm::rotate(baseModel, glm::radians(-45.0f), glm::vec3(0.0f, 0.0f, 1.0f));
}
worldTile::~worldTile()
{
cleanup();
}
void worldTile::cleanup()
{
}
void worldTile::setup()
{
float blockSize = 0.81f;
int worldSize = 2;
// 50 gives 15-16fps using drawElements
// 50 gives 480fps using drawElementsInstanced
// 50 gives 380fps using matrix drawElementsInstanced
for (int i = 0; i < worldSize; i++)
{
for (int j = 0; j < worldSize; j++)
{
float xPos = i * blockSize;
float yPos = j * blockSize;
glm::mat4 model = baseModel;
model = glm::translate(baseModel, glm::vec3(xPos, yPos, 0.0f));
modelMatrices.push_back(model);
if (i != 0)
{
model = glm::translate(baseModel, glm::vec3(-xPos, yPos, 0.0f));
modelMatrices.push_back(model);
}
if (j != 0)
{
model = glm::translate(baseModel, glm::vec3(xPos, -yPos, 0.0f));
modelMatrices.push_back(model);
}
if (i != 0 && j != 0)
{
model = glm::translate(baseModel, glm::vec3(-xPos, -yPos, 0.0f));
modelMatrices.push_back(model);
}
}
}
//modelMatrices[0] = glm::translate(modelMatrices[0], glm::vec3(0, 0, 0.2f));
colors = {
glm::vec3(0.55f, 0.71f, 0.29f), // 0 top green
glm::vec3(0.49f, 0.64f, 0.26f), // 1 front green
glm::vec3(0.45f, 0.59f, 0.24f), // 2 side green
glm::vec3(0.68f, 0.51f, 0.34f), // 3 brown
glm::vec3(0.73f, 0.55f, 0.36f), // 4 front brown
glm::vec3(0.62f, 0.47f, 0.35f), // 5 side brown
};
vertices = {
// top face
-0.4f, -0.4f, 0.1f, // 0
0.4f, -0.4f, 0.1f,
0.4f, 0.4f, 0.1f,
-0.4f, 0.4f, 0.1f,
// bottom face
-0.4f, -0.4f, -0.1f, // 4
0.4f, -0.4f, -0.1f,
0.4f, 0.4f, -0.1f,
-0.4f, 0.4f, -0.1f,
// left face - bottom
-0.4f, 0.4f, 0.0f, // 8
-0.4f, 0.4f, -0.1f,
-0.4f, -0.4f, -0.1f,
-0.4f, -0.4f, 0.0f,
// left face - top
-0.4f, 0.4f, 0.1f, // 12
-0.4f, 0.4f, -0.0f,
-0.4f, -0.4f, -0.0f,
-0.4f, -0.4f, 0.1f,
// right face - bottom
0.4f, 0.4f, 0.0f, // 16
0.4f, 0.4f, -0.1f,
0.4f, -0.4f, -0.1f,
0.4f, -0.4f, 0.0f,
// right face - top
0.4f, 0.4f, 0.1f, // 20
0.4f, 0.4f, -0.0f,
0.4f, -0.4f, -0.0f,
0.4f, -0.4f, 0.1f,
// left side face - bottom
-0.4f, -0.4f, -0.1f, // 24
0.4f, -0.4f, -0.1f,
0.4f, -0.4f, 0.0f,
-0.4f, -0.4f, 0.0f,
// left side face - top
-0.4f, -0.4f, -0.0f, // 28
0.4f, -0.4f, -0.0f,
0.4f, -0.4f, 0.1f,
-0.4f, -0.4f, 0.1f,
// back face - bottom
-0.4f, 0.4f, -0.1f, // 32
0.4f, 0.4f, -0.1f,
0.4f, 0.4f, 0.0f,
-0.4f, 0.4f, 0.0f,
// back face - top
-0.4f, 0.4f, -0.0f, // 36
0.4f, 0.4f, -0.0f,
0.4f, 0.4f, 0.1f,
-0.4f, 0.4f, 0.1f,
};
indices = { // note that we start from 0!
0, 1, 3, // first Triangle
1, 2, 3, // second Triangle
4, 5, 7,
5, 6, 7,
8,9,11,
9,10,11,
12,13,15,
13,14,15,
16,17,19,
17,18,19,
20,21,23,
21,22,23,
24,25,27,
25,26,27,
28,29,31,
29,30,31,
32,33,35,
33,34,35,
36,37,39,
37,38,39,
};
std::cout << "world title draw type" << std::endl;
glGenVertexArrays(1, VAO);
glGenBuffers(1, VBO);
glGenBuffers(1, EBO); // for index drawing
glGenBuffers(1, &matrixBuffer);
reloadBuffers();
glEnableVertexAttribArray(0);
glEnableVertexAttribArray(1);
glEnableVertexAttribArray(2);
glEnableVertexAttribArray(3);
glEnableVertexAttribArray(4);
glEnableVertexAttribArray(5);
glBindBuffer(GL_ARRAY_BUFFER, VBO[0]);
// position attribute
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 3 * sizeof(float), (void*)0);
// color attribute
//glVertexAttribPointer(1, 1, GL_FLOAT, GL_FALSE, 4 * sizeof(float), (void*)(3 * sizeof(float)));
// matrix attribute
// set attribute pointers for matrix (4 times vec4)
glBindBuffer(GL_ARRAY_BUFFER, matrixBuffer);
glVertexAttribPointer(2, 4, GL_FLOAT, GL_FALSE, sizeof(glm::mat4), (void*)0);
glVertexAttribPointer(3, 4, GL_FLOAT, GL_FALSE, sizeof(glm::mat4), (void*)(1 * sizeof(glm::vec4)));
glVertexAttribPointer(4, 4, GL_FLOAT, GL_FALSE, sizeof(glm::mat4), (void*)(2 * sizeof(glm::vec4)));
glVertexAttribPointer(5, 4, GL_FLOAT, GL_FALSE, sizeof(glm::mat4), (void*)(3 * sizeof(glm::vec4)));
glVertexAttribDivisor(2, 1);
glVertexAttribDivisor(3, 1);
glVertexAttribDivisor(4, 1);
glVertexAttribDivisor(5, 1);
glBindBuffer(GL_ARRAY_BUFFER, 0); //unbind
ourShader.use();
ourShader.setVec3("colors", 6, colors.data());
}
bool mouseDown = false;
glm::mat4 aProjection = glm::mat4(1.0f);
glm::mat4 aView = glm::mat4(1.0f);
void worldTile::processInput(GLFWwindow* window)
{
if (glfwGetMouseButton(window, GLFW_MOUSE_BUTTON_LEFT) == GLFW_RELEASE && mouseDown == true)
{
std::cout << "Mouse button released" << std::endl;
mouseDown = false;
}
if (glfwGetMouseButton(window, GLFW_MOUSE_BUTTON_LEFT) == GLFW_PRESS && mouseDown == false)
{
double xpos, ypos;
glfwGetCursorPos(window, &xpos, &ypos);
//ypos = 600 - ypos;
mouseDown = true;
unsigned char pixeldata[4];
GLfloat depth;
// reading pixel data at current cursor position ...
glReadBuffer(GL_COLOR_ATTACHMENT1); // read from second framebuffer layer
glReadPixels(xpos, 600 - ypos, 1, 1, GL_RGBA, GL_UNSIGNED_BYTE, pixeldata);
glReadPixels(xpos, 600 - ypos, 1, 1, GL_DEPTH_COMPONENT, GL_FLOAT, &depth);
glm::vec4 viewport = glm::vec4(0, 0, 800, 600);
glm::vec3 wincoord = glm::vec3(xpos, 600 - ypos, depth);
glm::mat4 baseModel = glm::mat4(1.0f);
baseModel = glm::rotate(baseModel, glm::radians(-45.0f), glm::vec3(1.0f, 0.0f, 0.0f));
glm::vec3 objcoord = glm::unProject(wincoord, baseModel, aProjection, viewport);
printf("Coordinates in object space: %f, %f, %f\n", objcoord.x, objcoord.y, objcoord.z);
int modelIndex = 0;
// TODO: find out which model from modelMatrices was clicked on
modelMatrices[0] = glm::translate(modelMatrices[0], glm::vec3(0, 0, 0.2f));
glBindBuffer(GL_ARRAY_BUFFER, matrixBuffer);
glBufferSubData(GL_ARRAY_BUFFER, 0, sizeof(glm::mat4), &modelMatrices.data()[0]);
//glBufferData(GL_ARRAY_BUFFER, modelMatrices.size() * sizeof(glm::mat4), &modelMatrices.data()[0], drawType);
// convert pixel color back to (int)ID ...
//unsigned int m_trackedID = (pixeldata[0] << 0) | (pixeldata[1] << 8) | (pixeldata[2] << 16) | (pixeldata[3] << 24);
// ------------
//std::cout << "Mouse button pressed: " << xpos << "-" << ypos << " - " << depth << " - " << m_trackedID << std::endl;
}
if (isPressed(window, GLFW_KEY_Z))
{
for (int i = 0; i < 40; i++)
{
int index = i * 4;
vertices[index] -= 0.01f;
glBindBuffer(GL_ARRAY_BUFFER, VBO[0]);
glBufferSubData(GL_ARRAY_BUFFER, index * sizeof(float), sizeof(float), &vertices[index]);
}
}
else if (isPressed(window, GLFW_KEY_X))
{
for (int i = 0; i < 40; i++)
{
int index = i * 4;
vertices[index] += 0.01f;
glBindBuffer(GL_ARRAY_BUFFER, VBO[0]);
glBufferSubData(GL_ARRAY_BUFFER, index * sizeof(float), sizeof(float), &vertices[index]);
}
}
}
void worldTile::draw(glm::mat4& currentModel, glm::mat4& currentProjection, glm::mat4& currentView)
{
ourShader.use();
ourShader.setMat4("projection", currentProjection);
ourShader.setMat4("view", currentView);
aProjection = currentProjection;
aView = currentView;
glBindVertexArray(VAO[0]);
glDrawElementsInstanced(GL_TRIANGLES, indices.size(), GL_UNSIGNED_INT, 0, modelMatrices.size());
}
void worldTile::reloadBuffers()
{
glBindVertexArray(VAO[0]);
// load vertex buffers
glBindBuffer(GL_ARRAY_BUFFER, VBO[0]);
glBufferData(GL_ARRAY_BUFFER, vertices.size() * sizeof(float), vertices.data(), drawType);
// load index buffers
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, EBO[0]);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, indices.size() * sizeof(unsigned int), indices.data(), drawType);
// load matrix buffer
glBindBuffer(GL_ARRAY_BUFFER, matrixBuffer);
glBufferData(GL_ARRAY_BUFFER, modelMatrices.size() * sizeof(glm::mat4), &modelMatrices.data()[0], drawType);
}
非常感谢任何帮助。
我想通了。
调用 unproject 时，我必须执行与我在场景和模型上完成的任何平移和旋转相反的操作。
所以我有以下模型被传递到 unproject:
glm::mat4 model = glm::mat4(1.0f);
model = glm::translate(model, glm::vec3(0, 0, zoffset));
model = glm::rotate(model, glm::radians(-45.0f), glm::vec3(1.0f, 0.0f, 0.0f));
model = glm::rotate(model, glm::radians(-45.0f), glm::vec3(0.0f, 0.0f, 1.0f));
glm::vec3 objcoord = glm::unProject(wincoord, model, aProjection, viewport);
我还必须将场景投影和 zoffset（用于缩放）传递给我的模型。
我还有一个额外的向量来跟踪我所有对象的世界位置，所以在我调用 unproject 之后，我可以使用计算出的工作坐标来确定我点击了哪个立方体。这是一些额外的工作，但它确实有效。我可以清理它以使用聪明的算法或其他东西来找出选择了哪个立方体。
但这是我所做工作的基础。
我正在经历 learnopengl.com 并尝试制作 3d 等距场景。
到目前为止，我已经很好地工作了。
但是 learnopengl 课程中没有的内容是如何检测 3d 中的鼠标点击 space。
我正在使用 mat4 向量的实例绘图来绘制世界的每个立方体。
接下来我想做的是点击每个立方体并修改它（现在只需更改 z 位置）。
我找到了一些关于使用 glReadPixels 的文章，但是由于我的等距投影，x 和/或 y 坐标似乎不正确。
此外，由于我使用的是实例化绘图，所以我不确定如何确定矢量中的哪个实例被单击。
我的代码在 git 中心 here。
这是主要的 class 我用来绘制立方体的：
#include "worldTile.h"
worldTile::worldTile() : drawable("instance.shader.vs", "instance.shader.fs")
{
drawType = GL_STATIC_DRAW;
baseModel = glm::mat4(1.0f);
baseModel = glm::rotate(baseModel, glm::radians(-45.0f), glm::vec3(1.0f, 0.0f, 0.0f));
baseModel = glm::rotate(baseModel, glm::radians(0.0f), glm::vec3(0.0f, 1.0f, 0.0f));
baseModel = glm::rotate(baseModel, glm::radians(-45.0f), glm::vec3(0.0f, 0.0f, 1.0f));
}
worldTile::~worldTile()
{
cleanup();
}
void worldTile::cleanup()
{
}
void worldTile::setup()
{
float blockSize = 0.81f;
int worldSize = 2;
// 50 gives 15-16fps using drawElements
// 50 gives 480fps using drawElementsInstanced
// 50 gives 380fps using matrix drawElementsInstanced
for (int i = 0; i < worldSize; i++)
{
for (int j = 0; j < worldSize; j++)
{
float xPos = i * blockSize;
float yPos = j * blockSize;
glm::mat4 model = baseModel;
model = glm::translate(baseModel, glm::vec3(xPos, yPos, 0.0f));
modelMatrices.push_back(model);
if (i != 0)
{
model = glm::translate(baseModel, glm::vec3(-xPos, yPos, 0.0f));
modelMatrices.push_back(model);
}
if (j != 0)
{
model = glm::translate(baseModel, glm::vec3(xPos, -yPos, 0.0f));
modelMatrices.push_back(model);
}
if (i != 0 && j != 0)
{
model = glm::translate(baseModel, glm::vec3(-xPos, -yPos, 0.0f));
modelMatrices.push_back(model);
}
}
}
//modelMatrices[0] = glm::translate(modelMatrices[0], glm::vec3(0, 0, 0.2f));
colors = {
glm::vec3(0.55f, 0.71f, 0.29f), // 0 top green
glm::vec3(0.49f, 0.64f, 0.26f), // 1 front green
glm::vec3(0.45f, 0.59f, 0.24f), // 2 side green
glm::vec3(0.68f, 0.51f, 0.34f), // 3 brown
glm::vec3(0.73f, 0.55f, 0.36f), // 4 front brown
glm::vec3(0.62f, 0.47f, 0.35f), // 5 side brown
};
vertices = {
// top face
-0.4f, -0.4f, 0.1f, // 0
0.4f, -0.4f, 0.1f,
0.4f, 0.4f, 0.1f,
-0.4f, 0.4f, 0.1f,
// bottom face
-0.4f, -0.4f, -0.1f, // 4
0.4f, -0.4f, -0.1f,
0.4f, 0.4f, -0.1f,
-0.4f, 0.4f, -0.1f,
// left face - bottom
-0.4f, 0.4f, 0.0f, // 8
-0.4f, 0.4f, -0.1f,
-0.4f, -0.4f, -0.1f,
-0.4f, -0.4f, 0.0f,
// left face - top
-0.4f, 0.4f, 0.1f, // 12
-0.4f, 0.4f, -0.0f,
-0.4f, -0.4f, -0.0f,
-0.4f, -0.4f, 0.1f,
// right face - bottom
0.4f, 0.4f, 0.0f, // 16
0.4f, 0.4f, -0.1f,
0.4f, -0.4f, -0.1f,
0.4f, -0.4f, 0.0f,
// right face - top
0.4f, 0.4f, 0.1f, // 20
0.4f, 0.4f, -0.0f,
0.4f, -0.4f, -0.0f,
0.4f, -0.4f, 0.1f,
// left side face - bottom
-0.4f, -0.4f, -0.1f, // 24
0.4f, -0.4f, -0.1f,
0.4f, -0.4f, 0.0f,
-0.4f, -0.4f, 0.0f,
// left side face - top
-0.4f, -0.4f, -0.0f, // 28
0.4f, -0.4f, -0.0f,
0.4f, -0.4f, 0.1f,
-0.4f, -0.4f, 0.1f,
// back face - bottom
-0.4f, 0.4f, -0.1f, // 32
0.4f, 0.4f, -0.1f,
0.4f, 0.4f, 0.0f,
-0.4f, 0.4f, 0.0f,
// back face - top
-0.4f, 0.4f, -0.0f, // 36
0.4f, 0.4f, -0.0f,
0.4f, 0.4f, 0.1f,
-0.4f, 0.4f, 0.1f,
};
indices = { // note that we start from 0!
0, 1, 3, // first Triangle
1, 2, 3, // second Triangle
4, 5, 7,
5, 6, 7,
8,9,11,
9,10,11,
12,13,15,
13,14,15,
16,17,19,
17,18,19,
20,21,23,
21,22,23,
24,25,27,
25,26,27,
28,29,31,
29,30,31,
32,33,35,
33,34,35,
36,37,39,
37,38,39,
};
std::cout << "world title draw type" << std::endl;
glGenVertexArrays(1, VAO);
glGenBuffers(1, VBO);
glGenBuffers(1, EBO); // for index drawing
glGenBuffers(1, &matrixBuffer);
reloadBuffers();
glEnableVertexAttribArray(0);
glEnableVertexAttribArray(1);
glEnableVertexAttribArray(2);
glEnableVertexAttribArray(3);
glEnableVertexAttribArray(4);
glEnableVertexAttribArray(5);
glBindBuffer(GL_ARRAY_BUFFER, VBO[0]);
// position attribute
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 3 * sizeof(float), (void*)0);
// color attribute
//glVertexAttribPointer(1, 1, GL_FLOAT, GL_FALSE, 4 * sizeof(float), (void*)(3 * sizeof(float)));
// matrix attribute
// set attribute pointers for matrix (4 times vec4)
glBindBuffer(GL_ARRAY_BUFFER, matrixBuffer);
glVertexAttribPointer(2, 4, GL_FLOAT, GL_FALSE, sizeof(glm::mat4), (void*)0);
glVertexAttribPointer(3, 4, GL_FLOAT, GL_FALSE, sizeof(glm::mat4), (void*)(1 * sizeof(glm::vec4)));
glVertexAttribPointer(4, 4, GL_FLOAT, GL_FALSE, sizeof(glm::mat4), (void*)(2 * sizeof(glm::vec4)));
glVertexAttribPointer(5, 4, GL_FLOAT, GL_FALSE, sizeof(glm::mat4), (void*)(3 * sizeof(glm::vec4)));
glVertexAttribDivisor(2, 1);
glVertexAttribDivisor(3, 1);
glVertexAttribDivisor(4, 1);
glVertexAttribDivisor(5, 1);
glBindBuffer(GL_ARRAY_BUFFER, 0); //unbind
ourShader.use();
ourShader.setVec3("colors", 6, colors.data());
}
bool mouseDown = false;
glm::mat4 aProjection = glm::mat4(1.0f);
glm::mat4 aView = glm::mat4(1.0f);
void worldTile::processInput(GLFWwindow* window)
{
if (glfwGetMouseButton(window, GLFW_MOUSE_BUTTON_LEFT) == GLFW_RELEASE && mouseDown == true)
{
std::cout << "Mouse button released" << std::endl;
mouseDown = false;
}
if (glfwGetMouseButton(window, GLFW_MOUSE_BUTTON_LEFT) == GLFW_PRESS && mouseDown == false)
{
double xpos, ypos;
glfwGetCursorPos(window, &xpos, &ypos);
//ypos = 600 - ypos;
mouseDown = true;
unsigned char pixeldata[4];
GLfloat depth;
// reading pixel data at current cursor position ...
glReadBuffer(GL_COLOR_ATTACHMENT1); // read from second framebuffer layer
glReadPixels(xpos, 600 - ypos, 1, 1, GL_RGBA, GL_UNSIGNED_BYTE, pixeldata);
glReadPixels(xpos, 600 - ypos, 1, 1, GL_DEPTH_COMPONENT, GL_FLOAT, &depth);
glm::vec4 viewport = glm::vec4(0, 0, 800, 600);
glm::vec3 wincoord = glm::vec3(xpos, 600 - ypos, depth);
glm::mat4 baseModel = glm::mat4(1.0f);
baseModel = glm::rotate(baseModel, glm::radians(-45.0f), glm::vec3(1.0f, 0.0f, 0.0f));
glm::vec3 objcoord = glm::unProject(wincoord, baseModel, aProjection, viewport);
printf("Coordinates in object space: %f, %f, %f\n", objcoord.x, objcoord.y, objcoord.z);
int modelIndex = 0;
// TODO: find out which model from modelMatrices was clicked on
modelMatrices[0] = glm::translate(modelMatrices[0], glm::vec3(0, 0, 0.2f));
glBindBuffer(GL_ARRAY_BUFFER, matrixBuffer);
glBufferSubData(GL_ARRAY_BUFFER, 0, sizeof(glm::mat4), &modelMatrices.data()[0]);
//glBufferData(GL_ARRAY_BUFFER, modelMatrices.size() * sizeof(glm::mat4), &modelMatrices.data()[0], drawType);
// convert pixel color back to (int)ID ...
//unsigned int m_trackedID = (pixeldata[0] << 0) | (pixeldata[1] << 8) | (pixeldata[2] << 16) | (pixeldata[3] << 24);
// ------------
//std::cout << "Mouse button pressed: " << xpos << "-" << ypos << " - " << depth << " - " << m_trackedID << std::endl;
}
if (isPressed(window, GLFW_KEY_Z))
{
for (int i = 0; i < 40; i++)
{
int index = i * 4;
vertices[index] -= 0.01f;
glBindBuffer(GL_ARRAY_BUFFER, VBO[0]);
glBufferSubData(GL_ARRAY_BUFFER, index * sizeof(float), sizeof(float), &vertices[index]);
}
}
else if (isPressed(window, GLFW_KEY_X))
{
for (int i = 0; i < 40; i++)
{
int index = i * 4;
vertices[index] += 0.01f;
glBindBuffer(GL_ARRAY_BUFFER, VBO[0]);
glBufferSubData(GL_ARRAY_BUFFER, index * sizeof(float), sizeof(float), &vertices[index]);
}
}
}
void worldTile::draw(glm::mat4& currentModel, glm::mat4& currentProjection, glm::mat4& currentView)
{
ourShader.use();
ourShader.setMat4("projection", currentProjection);
ourShader.setMat4("view", currentView);
aProjection = currentProjection;
aView = currentView;
glBindVertexArray(VAO[0]);
glDrawElementsInstanced(GL_TRIANGLES, indices.size(), GL_UNSIGNED_INT, 0, modelMatrices.size());
}
void worldTile::reloadBuffers()
{
glBindVertexArray(VAO[0]);
// load vertex buffers
glBindBuffer(GL_ARRAY_BUFFER, VBO[0]);
glBufferData(GL_ARRAY_BUFFER, vertices.size() * sizeof(float), vertices.data(), drawType);
// load index buffers
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, EBO[0]);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, indices.size() * sizeof(unsigned int), indices.data(), drawType);
// load matrix buffer
glBindBuffer(GL_ARRAY_BUFFER, matrixBuffer);
glBufferData(GL_ARRAY_BUFFER, modelMatrices.size() * sizeof(glm::mat4), &modelMatrices.data()[0], drawType);
}
非常感谢任何帮助。
我想通了。
调用 unproject 时，我必须执行与我在场景和模型上完成的任何平移和旋转相反的操作。
所以我有以下模型被传递到 unproject:
glm::mat4 model = glm::mat4(1.0f);
model = glm::translate(model, glm::vec3(0, 0, zoffset));
model = glm::rotate(model, glm::radians(-45.0f), glm::vec3(1.0f, 0.0f, 0.0f));
model = glm::rotate(model, glm::radians(-45.0f), glm::vec3(0.0f, 0.0f, 1.0f));
glm::vec3 objcoord = glm::unProject(wincoord, model, aProjection, viewport);
我还必须将场景投影和 zoffset（用于缩放）传递给我的模型。
我还有一个额外的向量来跟踪我所有对象的世界位置，所以在我调用 unproject 之后，我可以使用计算出的工作坐标来确定我点击了哪个立方体。这是一些额外的工作，但它确实有效。我可以清理它以使用聪明的算法或其他东西来找出选择了哪个立方体。
但这是我所做工作的基础。