Whenever i use matrix multiplication i get a black screen [closed] - c++

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I am having this problem while trying to run OpenGl code on mac OS, so I get a triangle on the screen, but whenever i try to multiply a matrix (that is not the identity matrix) i get a black screen, so i stripped all my code away looking for a mistake but i still got the same mistake, then i got this
generic code from learnOpengl and i tried to run it but i got the same problem so i don't think the problem is in he code but rather this makefile i use to compile it with.
CC := g++
SOURCE_DIR := Sources/ Includes/ Libs/ graphics/ Other/stb_image/
Includes/glm/gtc/ Includes/glm/
INCLUDE_DIR := -ILibs/ -IIncludes/ -IOther/ -ISources/ -Igraphics/ -
Ishaders/ -I/usr/X11R6/include
LIBS_DIR := -L/usr/local/Cellar/glfw/3.2.1 -lglfw3
CFLAGS := $(CC) -std=c++14 -c -Wall
LFLAGS := -o
FRAMEWORKS := -I/usr/X11R6/include -framework Cocoa -framework OpenGL -
framework IOKit -framework CoreVideo -framework GLUT
EXE := App
APP_DIR := ApplicationDir/
OBJ_DIR := libraries/
SOURCE_FILES := $(foreach dir, $(SOURCE_DIR), $(wildcard $(dir)*.cpp))
OBJ_FILES := $(wildcard Objects/*)
SOURCE_FILES += Other/glad.c
all :
make build ; \
make run
build : $(EXE)
$(EXE)
$(EXE): $(OBJ_FILES)
$(CC) $(FRAMEWORKS) $(LIBS_DIR) $(OBJ_FILES) $(LFLAGS) $(EXE)
$(OBJ_FILES) : $(SOURCE_FILES)
for file in $(SOURCE_FILES) ; do \
$(CFLAGS) $(INCLUDE_DIR) $$file ; \
mv *.o Objects ; \
done
run:
echo && ./$(EXE) && echo
clean :
rm -f $(EXE) $(OBJ_FILES)
my code :
#include <glad/glad.h>
#include <GLFW/glfw3.h>
#include <glm/glm.hpp>
#include <glm/gtc/matrix_transform.hpp>
#include <glm/gtc/type_ptr.hpp>
#include <iostream>
void framebuffer_size_callback(GLFWwindow* window, int width, int height);
void processInput(GLFWwindow *window);
// settings
const unsigned int SCR_WIDTH = 800;
const unsigned int SCR_HEIGHT = 600;
static const char *vertexShaderSource = R"(
#version 330 core
layout (location = 0) in vec3 aPos;
layout (location = 1) in vec3 aColor;
out vec3 ourColor;
uniform mat4 Model;
uniform mat4 View;
uniform mat4 Projection;
uniform vec4 Colour;
out vec4 unifColour;
void main()
{
mat4 transform = Projection;
gl_Position = transform * vec4(aPos, 1.0);
ourColor = aColor;
unifColour = Colour;
}
)";
const char *fragmentShaderSource = R"(
#version 330 core
out vec4 FragColor;
in vec3 ourColor;
in vec4 unifColour;
void main()
{
FragColor = unifColour;
})";
int main()
{
// glfw: initialize and configure
// ------------------------------
glfwInit();
glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 4);
glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 1);
glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE);
// std::cout << glGetString(GL_SHADING_LANGUAGE_VERSION) << std::endl;
// glfw window creation
// --------------------
GLFWwindow* window = glfwCreateWindow(SCR_WIDTH, SCR_HEIGHT, "LearnOpenGL", NULL, NULL);
if (window == NULL)
{
std::cout << "Failed to create GLFW window" << std::endl;
glfwTerminate();
return -1;
}
glfwMakeContextCurrent(window);
glfwSetFramebufferSizeCallback(window, framebuffer_size_callback);
// glad: load all OpenGL function pointers
// ---------------------------------------
if (!gladLoadGLLoader((GLADloadproc)glfwGetProcAddress))
{
std::cout << "Failed to initialize GLAD" << std::endl;
return -1;
}
glEnable(GL_DEPTH_TEST);
// build and compile our shader program
// ------------------------------------
// vertex shader
int vertexShader = glCreateShader(GL_VERTEX_SHADER);
glShaderSource(vertexShader, 1, &vertexShaderSource, NULL);
glCompileShader(vertexShader);
// check for shader compile errors
int success;
char infoLog[512];
glGetShaderiv(vertexShader, GL_COMPILE_STATUS, &success);
if (!success)
{
glGetShaderInfoLog(vertexShader, 512, NULL, infoLog);
std::cout << "ERROR::SHADER::VERTEX::COMPILATION_FAILED\n" << infoLog << std::endl;
}
// fragment shader
int fragmentShader = glCreateShader(GL_FRAGMENT_SHADER);
glShaderSource(fragmentShader, 1, &fragmentShaderSource, NULL);
glCompileShader(fragmentShader);
// check for shader compile errors
glGetShaderiv(fragmentShader, GL_COMPILE_STATUS, &success);
if (!success)
{
glGetShaderInfoLog(fragmentShader, 512, NULL, infoLog);
std::cout << "ERROR::SHADER::FRAGMENT::COMPILATION_FAILED\n" << infoLog << std::endl;
}
// link shaders
int shaderProgram = glCreateProgram();
glAttachShader(shaderProgram, vertexShader);
glAttachShader(shaderProgram, fragmentShader);
glLinkProgram(shaderProgram);
// check for linking errors
glGetProgramiv(shaderProgram, GL_LINK_STATUS, &success);
if (!success) {
glGetProgramInfoLog(shaderProgram, 512, NULL, infoLog);
std::cout << "ERROR::SHADER::PROGRAM::LINKING_FAILED\n" << infoLog << std::endl;
}
glDeleteShader(vertexShader);
glDeleteShader(fragmentShader);
// set up vertex data (and buffer(s)) and configure vertex attributes
// ------------------------------------------------------------------
float vertices[] = {
// positions // colors
0.5f, -0.5f, 0.0f, 1.0f, 0.0f, 0.0f, // bottom right
-0.5f, -0.5f, 0.0f, 0.0f, 1.0f, 0.0f, // bottom left
0.0f, 0.5f, 0.0f, 0.0f, 0.0f, 1.0f // top
};
unsigned int VBO, VAO;
glGenVertexArrays(1, &VAO);
glGenBuffers(1, &VBO);
// bind the Vertex Array Object first, then bind and set vertex buffer(s), and then configure vertex attributes(s).
glBindVertexArray(VAO);
glBindBuffer(GL_ARRAY_BUFFER, VBO);
glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
// position attribute
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 6 * sizeof(float), (void*)0);
glEnableVertexAttribArray(0);
// color attribute
glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 6 * sizeof(float), (void*)(3 * sizeof(float)));
glEnableVertexAttribArray(1);
// You can unbind the VAO afterwards so other VAO calls won't accidentally modify this VAO, but this rarely happens. Modifying other
// VAOs requires a call to glBindVertexArray anyways so we generally don't unbind VAOs (nor VBOs) when it's not directly necessary.
// glBindVertexArray(0);
// as we only have a single shader, we could also just activate our shader once beforehand if we want to
glUseProgram(shaderProgram);
std::cout << shaderProgram << std::endl;
// render loop
// -----------
while (!glfwWindowShouldClose(window))
{
// input
// -----
processInput(window);
// render
// ------
glClearColor(0.2f, 0.3f, 0.3f, 1.0f);
glClear(GL_DEPTH_BUFFER_BIT | GL_COLOR_BUFFER_BIT);
// render the triangle
glBindVertexArray(VAO);
glDrawArrays(GL_TRIANGLES, 0, 3);
glm::mat4 Model(1.0f);
glm::mat4 View(1.0f);
glm::mat4 Projection(1.0f);
Projection = glm::perspective(glm::radians(55.0f), 800.0f/600.0f, 0.01f, 100.0f);
Model = glm::scale(Model, glm::vec3(0.5f, 0.5f, 0.5f));
unsigned int location = glGetUniformLocation(shaderProgram, "Colour");
glm::vec4 colour = glm::vec4(1.0, 0.0, 1.0, 1.0);
glUniform4fv(location, 1, &colour[0]);
glUseProgram(shaderProgram);
GLint model = glGetUniformLocation(shaderProgram, "Model" );
glUniformMatrix4fv(model, 1, GL_FALSE, glm::value_ptr(Model));
GLint view = glGetUniformLocation(shaderProgram, "View" );
glUniformMatrix4fv(view, 1, GL_FALSE, glm::value_ptr(View));
GLint projection = glGetUniformLocation(shaderProgram, "Projection" );
glUniformMatrix4fv(projection, 1, GL_FALSE, glm::value_ptr(Projection));
glBindVertexArray(VAO);
glDrawArrays(GL_TRIANGLES, 0, 3);
// glfw: swap buffers and poll IO events (keys pressed/released, mouse moved etc.)
// -------------------------------------------------------------------------------
glfwSwapBuffers(window);
glfwPollEvents();
}
// optional: de-allocate all resources once they've outlived their purpose:
// ------------------------------------------------------------------------
glDeleteVertexArrays(1, &VAO);
glDeleteBuffers(1, &VBO);
// glfw: terminate, clearing all previously allocated GLFW resources.
// ------------------------------------------------------------------
glfwTerminate();
return 0;
}
// process all input: query GLFW whether relevant keys are pressed/released this frame and react accordingly
// ---------------------------------------------------------------------------------------------------------
void processInput(GLFWwindow *window)
{
if (glfwGetKey(window, GLFW_KEY_ESCAPE) == GLFW_PRESS)
glfwSetWindowShouldClose(window, true);
}
// glfw: whenever the window size changed (by OS or user resize) this callback function executes
// ---------------------------------------------------------------------------------------------
void framebuffer_size_callback(GLFWwindow* window, int width, int height)
{
// make sure the viewport matches the new window dimensions; note that width and
// height will be significantly larger than specified on retina displays.
glViewport(0, 0, width, height);
}

Answer 1

You do not use a view matrix, so you have to set up the position of the model in view space. In view space the X-axis points from the left to the right, the Y-axis points from the bottom to the top. The z-Axis points out of the viewport (cross product of x-axis and y-axis in a Right-hand system).
This means you have to shift the mesh along the negative Z-axis, in between the near and the far plane, which is defined by the projection matrix ([0.01, 100.0] in your case).
Use the Model, View and Projection matrix in the fragment shader:
gl_Position = Projection * View * Model * vec4(aPos, 1.0);
Set up the model matrix with a translation along the negative Z-axis (e.g. -2.0):
glm::mat4 Model(1.0f);
Model = glm::translate(Model, glm::vec3(0.0f, 0.0f, -2.0f));