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Finish hello triangle

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This commit is contained in:
Joseph Ferano 2023-10-13 22:18:59 +07:00
parent 8326b110df
commit 32228da922
2 changed files with 20 additions and 8 deletions
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5
README.org
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@ -17,5 +17,6 @@ For faster compilation, compile glad;
gcc -Ilibs/glad/include/ -c libs/glad/src/glad.c
#+end_src
* Terms
VBO - vertex buffer objects
VAO - vertex array object
VBO - Vertex Buffer Objects
VAO - Vertex Array Object
EBO - Element Buffer Object

23
main.c
View File

@ -110,17 +110,25 @@ int main(void) {
glDeleteShader(fragmentShader);
float vertices[] = {
-0.5f, -0.5f, 0.0f,
0.5f, -0.5f, 0.0f,
0.0f, 0.5f, 0.0f
};
0.5f, 0.5f, 0.0f, // top right
0.5f, -0.5f, 0.0f, // bottom right
-0.5f, -0.5f, 0.0f, // bottom left
-0.5f, 0.5f, 0.0f // top left
};
unsigned int indices[] = { // note that we start from 0!
0, 1, 3, // first triangle
1, 2, 3 // second triangle
};
unsigned int VBO, VAO;
unsigned int VBO, VAO, EBO;
glGenVertexArrays(1, &VAO);
glGenBuffers(1, &EBO);
glGenBuffers(1, &VBO);
glBindVertexArray(VAO);
glBindBuffer(GL_ARRAY_BUFFER, VBO);
glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, EBO);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(indices), indices, GL_STATIC_DRAW);
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 3 * sizeof(float), (void*)0);
glEnableVertexAttribArray(0);
@ -136,7 +144,10 @@ int main(void) {
glUseProgram(shaderProgram);
glBindVertexArray(VAO);
glDrawArrays(GL_TRIANGLES, 0, 3);
// glDrawArrays(GL_TRIANGLES, 0, 3);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, EBO);
glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0);
glfwSwapBuffers(window);
glfwPollEvents();