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Add GLM and make the triangle move

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Nathan Chapman 2025-07-02 08:09:31 -06:00
parent 27452c30a5
commit 56cf609849
2 changed files with 42 additions and 18 deletions
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4
CMakeLists.txt
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@ -5,6 +5,7 @@ set(CMAKE_CXX_STANDARD 17)
find_package(OpenGL REQUIRED) find_package(OpenGL REQUIRED)
find_package(GLEW REQUIRED) find_package(GLEW REQUIRED)
find_package(glm REQUIRED)
find_package(glfw3 REQUIRED) find_package(glfw3 REQUIRED)
add_executable(opengl_test src/main.cpp) add_executable(opengl_test src/main.cpp)
@ -12,5 +13,6 @@ add_executable(opengl_test src/main.cpp)
target_link_libraries(opengl_test target_link_libraries(opengl_test
OpenGL::GL OpenGL::GL
GLEW::GLEW GLEW::GLEW
glm::glm
glfw glfw
) )

56
src/main.cpp
View File

@ -2,28 +2,31 @@
#include <string.h> #include <string.h>
#include <GL/glew.h> #include <GL/glew.h>
#include <GLFW/glfw3.h> #include <GLFW/glfw3.h>
#include <cmath>
// Window dimensions // Window dimensions
const GLint WIDTH = 800, HEIGHT = 600; const GLint WIDTH = 800, HEIGHT = 600;
// Vertex Shader // Vertex Shader
static const char *vertex_shader = " \n\ static const char *vertex_shader = " \n\
#version 330 \n\ #version 330 \n\
\n\ \n\
layout (location = 0) in vec3 pos; \n\ layout (location = 0) in vec3 pos; \n\
\n\ \n\
void main() { \n\ uniform float x_move; \n\
gl_Position = vec4(pos.x, pos.y, pos.z, 1.0); \n\ \n\
void main() { \n\
gl_Position = vec4(pos.x + x_move, pos.y, pos.z, 1.0); \n\
}"; }";
// Fragment shader // Fragment shader
static const char *fragment_shader = " \n\ static const char *fragment_shader = " \n\
#version 330 \n\ #version 330 \n\
\n\ \n\
out vec4 color; \n\ out vec4 color; \n\
\n\ \n\
void main() { \n\ void main() { \n\
color = vec4(1.0, 0.0, 0.0, 1.0); \n\ color = vec4(1.0, 0.0, 0.0, 1.0); \n\
}"; }";
bool add_shader(GLuint *program, const char *shader_code, GLenum shader_type) { bool add_shader(GLuint *program, const char *shader_code, GLenum shader_type) {
@ -51,7 +54,7 @@ bool add_shader(GLuint *program, const char *shader_code, GLenum shader_type) {
return true; return true;
} }
bool compile_shaders(GLuint *shader_program) { bool compile_shaders(GLuint *shader_program, GLuint *x_move) {
*shader_program = glCreateProgram(); *shader_program = glCreateProgram();
if (!shader_program) { if (!shader_program) {
@ -83,6 +86,8 @@ bool compile_shaders(GLuint *shader_program) {
return false; return false;
} }
*x_move = glGetUniformLocation(*shader_program, "x_move");
return true; return true;
} }
@ -109,7 +114,11 @@ void create_triangle(GLuint *VAO, GLuint *VBO) {
} }
int main() { int main() {
GLuint VAO, VBO, shader_program; GLuint VAO, VBO, shader_program, x_move;
bool direction = true;
float tri_offset = 0.0f;
float tri_max_offset = 0.7f;
float tri_increment = 0.005f;
// Initialize GLFW // Initialize GLFW
glfwInitHint(GLFW_PLATFORM, GLFW_PLATFORM_WAYLAND); glfwInitHint(GLFW_PLATFORM, GLFW_PLATFORM_WAYLAND);
@ -168,18 +177,31 @@ int main() {
// Create our triangle // Create our triangle
create_triangle(&VAO, &VBO); create_triangle(&VAO, &VBO);
compile_shaders(&shader_program); compile_shaders(&shader_program, &x_move);
// Loop until window is closed // Loop until window is closed
while (!glfwWindowShouldClose(window)) { while (!glfwWindowShouldClose(window)) {
// Get and handle user input events // Get and handle user input events
glfwPollEvents(); glfwPollEvents();
if (direction) {
tri_offset += tri_increment;
} else {
tri_offset -= tri_increment;
}
if (std::abs(tri_offset) >= tri_max_offset) {
direction = !direction;
}
// Clear window // Clear window
glClearColor(0.0f, 0.0f, 0.0f, 1.0f); glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT); glClear(GL_COLOR_BUFFER_BIT);
glUseProgram(shader_program); glUseProgram(shader_program);
glUniform1f(x_move, tri_offset);
glBindVertexArray(VAO); glBindVertexArray(VAO);
glDrawArrays(GL_TRIANGLES, 0, 3); glDrawArrays(GL_TRIANGLES, 0, 3);