Hey.New to OpenGL. i’m trying to get this skybox to work. Both the vertex and fragmentshaders for the skybox are compiling successfully, however the program is just entirely black.
i’m mostly suspicious against the main.cpp file being weird. Note: i also have a cube object in the main.cpp file.
Any input is appreciated. Thnx.
here’s the main.cpp file
// Include standard headers
#include <stdio.h>
#include <stdlib.h>
// Include GLEW
#include <GL/glew.h>
#include <vector>
#include <iostream>
// Include GLFW
#include <GLFW/glfw3.h>
GLFWwindow* window;
// Include GLM
#include <glm/glm.hpp>
#include <glm/gtc/matrix_transform.hpp>
using namespace glm;
#include <common/skyboxtex.hpp>
#include <common/shader.hpp>
#include <common/texture.hpp>
#include <common/controls.hpp>
#include <glm/gtc/type_ptr.hpp>
int main(void)
{
// Initialise GLFW
if (!glfwInit())
{
fprintf(stderr, "Failed to initialize GLFW
");
getchar();
return -1;
}
glfwWindowHint(GLFW_SAMPLES, 4);
glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE); // To make MacOS happy; should not be needed
glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
// Open a window and create its OpenGL context
window = glfwCreateWindow(1024, 768, "Tutorial 0 - Keyboard and Mouse", NULL, NULL);
if (window == NULL) {
fprintf(stderr, "Failed to open GLFW window. If you have an Intel GPU, they are not 3.3 compatible. Try the 2.1 version of the tutorials.
");
getchar();
glfwTerminate();
return -1;
}
glfwMakeContextCurrent(window);
// Initialize GLEW
glewExperimental = true; // Needed for core profile
if (glewInit() != GLEW_OK) {
fprintf(stderr, "Failed to initialize GLEW
");
getchar();
glfwTerminate();
return -1;
}
// Ensure we can capture the escape key being pressed below
glfwSetInputMode(window, GLFW_STICKY_KEYS, GL_TRUE);
// Hide the mouse and enable unlimited mouvement
glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_DISABLED);
// Set the mouse at the center of the screen
glfwPollEvents();
glfwSetCursorPos(window, 1024 / 2, 768 / 2);
// Enable depth test
glEnable(GL_DEPTH_TEST);
// Accept fragment if it closer to the camera than the former one
glDepthFunc(GL_LESS);
// Cull triangles which normal is not towards the camera
glEnable(GL_CULL_FACE);
GLuint VertexArrayID;
glGenVertexArrays(1, &VertexArrayID);
glBindVertexArray(VertexArrayID);
// Create and compile our GLSL program from the shaders
GLuint programID = LoadShaders("TransformVertexShader.vertexshader", "TextureFragmentShader.fragmentshader");
GLuint skyboxShader = LoadShaders("skybox.vertexshader", "skybox.fragmentshader");
// Get a handle for our "MVP" uniform
GLuint MatrixID = glGetUniformLocation(programID, "MVP");
GLuint ModelMatrixID = glGetUniformLocation(programID, "M");
GLuint ViewMatrixID = glGetUniformLocation(programID, "V");
// Load the texture
GLuint Texture = loadDDS("uvtemplate.DDS");
//cubeassss
// Get a handle for our "myTextureSampler" uniform
GLuint TextureID = glGetUniformLocation(programID,"myTextureSampler");
//potentially another handle? for skybox
float skyboxVertices[] = {
// positions
-1.0f, 1.0f, -1.0f,
-1.0f, -1.0f, -1.0f,
1.0f, -1.0f, -1.0f,
1.0f, -1.0f, -1.0f,
1.0f, 1.0f, -1.0f,
-1.0f, 1.0f, -1.0f,
-1.0f, -1.0f, 1.0f,
-1.0f, -1.0f, -1.0f,
-1.0f, 1.0f, -1.0f,
-1.0f, 1.0f, -1.0f,
-1.0f, 1.0f, 1.0f,
-1.0f, -1.0f, 1.0f,
1.0f, -1.0f, -1.0f,
1.0f, -1.0f, 1.0f,
1.0f, 1.0f, 1.0f,
1.0f, 1.0f, 1.0f,
1.0f, 1.0f, -1.0f,
1.0f, -1.0f, -1.0f,
-1.0f, -1.0f, 1.0f,
-1.0f, 1.0f, 1.0f,
1.0f, 1.0f, 1.0f,
1.0f, 1.0f, 1.0f,
1.0f, -1.0f, 1.0f,
-1.0f, -1.0f, 1.0f,
-1.0f, 1.0f, -1.0f,
1.0f, 1.0f, -1.0f,
1.0f, 1.0f, 1.0f,
1.0f, 1.0f, 1.0f,
-1.0f, 1.0f, 1.0f,
-1.0f, 1.0f, -1.0f,
-1.0f, -1.0f, -1.0f,
-1.0f, -1.0f, 1.0f,
1.0f, -1.0f, -1.0f,
1.0f, -1.0f, -1.0f,
-1.0f, -1.0f, 1.0f,
1.0f, -1.0f, 1.0f
};
// Our vertices. Tree consecutive floats give a 3D vertex; Three consecutive vertices give a triangle.
// A cube has 6 faces with 2 triangles each, so this makes 6*2=12 triangles, and 12*3 vertices
static const GLfloat g_vertex_buffer_data[] = {
-1.0f,-1.0f,-1.0f,
-1.0f,-1.0f, 1.0f,
-1.0f, 1.0f, 1.0f,
1.0f, 1.0f,-1.0f,
-1.0f,-1.0f,-1.0f,
-1.0f, 1.0f,-1.0f,
1.0f,-1.0f, 1.0f,
-1.0f,-1.0f,-1.0f,
1.0f,-1.0f,-1.0f,
1.0f, 1.0f,-1.0f,
1.0f,-1.0f,-1.0f,
-1.0f,-1.0f,-1.0f,
-1.0f,-1.0f,-1.0f,
-1.0f, 1.0f, 1.0f,
-1.0f, 1.0f,-1.0f,
1.0f,-1.0f, 1.0f,
-1.0f,-1.0f, 1.0f,
-1.0f,-1.0f,-1.0f,
-1.0f, 1.0f, 1.0f,
-1.0f,-1.0f, 1.0f,
1.0f,-1.0f, 1.0f,
1.0f, 1.0f, 1.0f,
1.0f,-1.0f,-1.0f,
1.0f, 1.0f,-1.0f,
1.0f,-1.0f,-1.0f,
1.0f, 1.0f, 1.0f,
1.0f,-1.0f, 1.0f,
1.0f, 1.0f, 1.0f,
1.0f, 1.0f,-1.0f,
-1.0f, 1.0f,-1.0f,
1.0f, 1.0f, 1.0f,
-1.0f, 1.0f,-1.0f,
-1.0f, 1.0f, 1.0f,
1.0f, 1.0f, 1.0f,
-1.0f, 1.0f, 1.0f,
1.0f,-1.0f, 1.0f
};
// Two UV coordinatesfor each vertex. They were created with Blender.
static const GLfloat g_uv_buffer_data[] = {
0.000059f, 0.000004f,
0.000103f, 0.336048f,
0.335973f, 0.335903f,
1.000023f, 0.000013f,
0.667979f, 0.335851f,
0.999958f, 0.336064f,
0.667979f, 0.335851f,
0.336024f, 0.671877f,
0.667969f, 0.671889f,
1.000023f, 0.000013f,
0.668104f, 0.000013f,
0.667979f, 0.335851f,
0.000059f, 0.000004f,
0.335973f, 0.335903f,
0.336098f, 0.000071f,
0.667979f, 0.335851f,
0.335973f, 0.335903f,
0.336024f, 0.671877f,
1.000004f, 0.671847f,
0.999958f, 0.336064f,
0.667979f, 0.335851f,
0.668104f, 0.000013f,
0.335973f, 0.335903f,
0.667979f, 0.335851f,
0.335973f, 0.335903f,
0.668104f, 0.000013f,
0.336098f, 0.000071f,
0.000103f, 0.336048f,
0.000004f, 0.671870f,
0.336024f, 0.671877f,
0.000103f, 0.336048f,
0.336024f, 0.671877f,
0.335973f, 0.335903f,
0.667969f, 0.671889f,
1.000004f, 0.671847f,
0.667979f, 0.335851f
};
//skybox image faces
std::vector <std::string>faces;
{
"right.BMP",
"left.BMP",
"top.BMP",
"bottom.BMP",
"front.BMP",
"back.BMP";
};
GLuint CubemapTexture = loadCubemap(faces);
//Cube
GLuint vertexbuffer;
glGenBuffers(1, &vertexbuffer);
glBindBuffer(GL_ARRAY_BUFFER, vertexbuffer);
glBufferData(GL_ARRAY_BUFFER, sizeof(g_vertex_buffer_data), g_vertex_buffer_data, GL_STATIC_DRAW);
GLuint uvbuffer;
glGenBuffers(1, &uvbuffer);
glBindBuffer(GL_ARRAY_BUFFER, uvbuffer);
glBufferData(GL_ARRAY_BUFFER, sizeof(g_uv_buffer_data), g_uv_buffer_data, GL_STATIC_DRAW);
//skybox
GLuint skyboxVAO, skyboxVBO;
glGenBuffers(1, &skyboxVBO);
glBindBuffer(GL_ARRAY_BUFFER, skyboxVBO);
glBufferData(GL_ARRAY_BUFFER, sizeof(skyboxVertices), &skyboxVertices, GL_STATIC_DRAW);
do{
// Clear the screen
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
// Use our shader for the cube
glUseProgram(programID);
// Compute the MVP matrix from keyboard and mouse input to be uniformed
computeMatricesFromInputs();
glm::mat4 ProjectionMatrix = getProjectionMatrix();
glm::mat4 ViewMatrix = getViewMatrix();
glm::mat4 ModelMatrix = glm::mat4(1.0);
glm::mat4 MVP = ProjectionMatrix * ViewMatrix * ModelMatrix;
// Send our transformation to the currently bound shader,
// in the "MVP" uniform .MatrixID = glGetUniformLocation(programID, "MVP");
glUniformMatrix4fv(MatrixID, 1, GL_FALSE, &MVP[0][0]);
// Bind our texture in Texture Unit 0 Cube
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_2D, Texture);
// Set our "myTextureSampler" sampler to use Texture Unit 0. Texture = LoadDDS
glUniform1i(TextureID, 0);
// 1rst attribute buffer : vertices
glEnableVertexAttribArray(0);
glBindBuffer(GL_ARRAY_BUFFER, vertexbuffer);
glVertexAttribPointer(
0, // attribute. No particular reason for 0, but must match the layout in the shader.
3, // size
GL_FLOAT, // type
GL_FALSE, // normalized?
0, // stride
(void*)0 // array buffer offset
);
// 2nd attribute buffer : UVs
glEnableVertexAttribArray(1);
glBindBuffer(GL_ARRAY_BUFFER, uvbuffer);
glVertexAttribPointer(
1, // attribute. No particular reason for 1, but must match the layout in the shader.
2, // size : U+V => 2
GL_FLOAT, // type
GL_FALSE, // normalized?
0, // stride
(void*)0 // array buffer offset
);
//Skybox
// Draw the triangle !
glDrawArrays(GL_TRIANGLES, 0, 12*3); // 12*3 indices starting at 0 -> 12 triangles
//cube
//cube
glm::mat4 ModelMatrix2 = glm::mat4(1.0);
ModelMatrix2 = glm::translate(ModelMatrix2, glm::vec3(2.0f, 0.0f, 0.0f));
glm::mat4 MVP2 = ProjectionMatrix * ViewMatrix * ModelMatrix2;
//ModelMatrix = GetModelMatrix
glUniformMatrix4fv(MatrixID, 1, GL_FALSE, &MVP2[0][0]);
glUniformMatrix4fv(ModelMatrixID, 1, GL_FALSE, &ModelMatrix2[0][0]);
// 2nd object
glDrawArrays(GL_TRIANGLES, 0, 12 * 3);
// 1rst attribute buffer : vertices
glEnableVertexAttribArray(0);
glBindBuffer(GL_ARRAY_BUFFER, vertexbuffer);
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 0, (void*)0);
// 2nd attribute buffer : UVs
glEnableVertexAttribArray(1);
glBindBuffer(GL_ARRAY_BUFFER, uvbuffer);
glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 0, (void*)0);
//3rd attribute buffer:skybox
glEnableVertexAttribArray(3);
glGenVertexArrays(1, &skyboxVAO);
glBindVertexArray(skyboxVAO);
glVertexAttribPointer(3, 3, GL_FLOAT, GL_FALSE, 3 * sizeof(GLfloat), (GLvoid*)0);
glBindVertexArray(0);
glDisableVertexAttribArray(0);
glDisableVertexAttribArray(1);
//newshit
glDepthFunc(GL_LEQUAL);
glUseProgram(skyboxShader);
//skybox matrix
glm::mat4 view = glm::mat4(glm::mat3(getViewMatrix()));
// skybox Uniform 4 INCLUDE glm value_PTR.hpp
glUniformMatrix4fv(glGetUniformLocation(skyboxShader, "view"), 1, GL_FALSE, glm::value_ptr(view));
glUniformMatrix4fv(glGetUniformLocation(skyboxShader, "Projection"), 1, GL_FALSE, glm::value_ptr(ProjectionMatrix));
//skybox
glBindVertexArray(skyboxVAO);
glBindTexture(GL_TEXTURE_CUBE_MAP, CubemapTexture); //CubemapTexture = loadCubemap(faces);
glDrawArrays(GL_TRIANGLES, 0, 36);
glBindVertexArray(0);
glDepthFunc(GL_LESS);
// Swap buffers
glfwSwapBuffers(window);
glfwPollEvents();
} // Check if the ESC key was pressed or the window was closed
while( glfwGetKey(window, GLFW_KEY_ESCAPE ) != GLFW_PRESS &&
glfwWindowShouldClose(window) == 0 );
// Cleanup VBO and shader
glDeleteBuffers(1, &vertexbuffer);
glDeleteBuffers(1, &uvbuffer);
glDeleteProgram(programID);
glDeleteTextures(1, &TextureID);
glDeleteVertexArrays(1, &VertexArrayID);
// Close OpenGL window and terminate GLFW
glfwTerminate();
return 0;
}
AND THE SKYBOX-TEXTURE FILE.HPP
#pragma once
#include "SOIL.h"
#define GLEW_STATIC
#include <GL/glew.h>
#include <vector>
int width, height, nrChannels;
unsigned char *data;
GLuint loadCubemap(std::vector<std::string> faces)
{
unsigned int textureID;
glGenTextures(1, &textureID);
glBindTexture(GL_TEXTURE_CUBE_MAP, textureID);
for (GLuint i = 0; i < faces.size(); i++)
{
unsigned char *data = SOIL_load_image(faces[i].c_str(), &width, &height, &nrChannels, 0);
if (data)
{
glTexImage2D(
GL_TEXTURE_CUBE_MAP_POSITIVE_X + i,
0, GL_RGB, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, data
);
SOIL_free_image_data(data);
}
else
{
printf("Cubemap texture failed to load at path:");
}
}
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_EDGE);
return textureID;
}