commit 59805d495e4c595f6abdf9ea7d716ad12e864a59
parent f465d3c30706dea3647cfdd546ae975436d86d8c
Author: mpizzzle <m@michaelpercival.xyz>
Date: Sun, 11 Oct 2020 00:22:51 +0100
draws a fricken triangle
Diffstat:
6 files changed, 216 insertions(+), 60 deletions(-)
diff --git a/Makefile b/Makefile
@@ -1,12 +1,12 @@
CXX = clang++
CXXFLAGS = -O2 -Wall -Wextra -pedantic -std=c++17 -I.
-LIBS= -lSDL2
+LIBS = -lGL -lglfw -lGLEW
+DEPS = shader.hpp
ODIR = obj
-_OBJ = penrose.o
-
+_OBJ = penrose.o shader.o
OBJ = $(patsubst %,$(ODIR)/%,$(_OBJ))
-$(ODIR)/%.o: %.cpp $(LIBS)
+$(ODIR)/%.o: %.cpp $(DEPS)
$(CXX) -c -o $@ $< $(CXXFLAGS)
penrose: $(OBJ) $(LIBS)
diff --git a/fragment.frag b/fragment.frag
@@ -0,0 +1,5 @@
+#version 330 core
+out vec3 color;
+void main() {
+ color = vec3(1,0,0);
+}
diff --git a/penrose.cpp b/penrose.cpp
@@ -1,68 +1,118 @@
-#include <SDL2/SDL.h>
+#include <GL/glew.h>
+#include <GLFW/glfw3.h>
+
#include <iostream>
+#include <fstream>
+#include <sstream>
#include <vector>
-class triangle {
-public:
- SDL_Point* points;
- std::vector<triangle*> subtriangles;
-};
-
-class t123 : public triangle {
-};
-
-class t124 : public triangle {
-};
-
-void draw(SDL_Renderer* Renderer, std::vector<triangle> triangles) {
- SDL_SetRenderDrawColor(Renderer, 0x33, 0x66, 0x99, SDL_ALPHA_OPAQUE);
- SDL_RenderClear(Renderer);
-
- SDL_SetRenderDrawColor(Renderer, 255, 255, 255, SDL_ALPHA_OPAQUE);
-
- for (triangle t : triangles) {
- SDL_RenderDrawLines(Renderer, t.points, 4);
- }
-
- SDL_RenderPresent(Renderer);
-}
+#include "shader.hpp"
+
+//class triangle {
+//public:
+// SDL_Point* points;
+// std::vector<triangle*> subtriangles;
+//};
+//
+//class t123 : public triangle {
+//};
+//
+//class t124 : public triangle {
+//};
+//
+//void draw(SDL_Renderer* Renderer, std::vector<triangle> triangles) {
+// SDL_SetRenderDrawColor(Renderer, 0x33, 0x66, 0x99, SDL_ALPHA_OPAQUE);
+// SDL_RenderClear(Renderer);
+//
+// SDL_SetRenderDrawColor(Renderer, 255, 255, 255, SDL_ALPHA_OPAQUE);
+//
+// for (triangle t : triangles) {
+// SDL_RenderDrawLines(Renderer, t.points, 4);
+// }
+//
+// SDL_RenderPresent(Renderer);
+//}
int main() {
- bool quit = false;
-
- SDL_DisplayMode current;
- SDL_Event event;
-
- SDL_Init(SDL_INIT_EVERYTHING);
- SDL_GetCurrentDisplayMode(0, ¤t);
- SDL_Log("Display #%d: current display mode is %dx%dpx @ %dhz.", 0, current.w, current.h, current.refresh_rate);
-
- std::vector<triangle> triangles;
-
- t123 t;
- SDL_Point points[4] = { {0, 480}, {320, 0}, {640, 480}, {0, 480} };
- t.points = points;
- triangles.push_back(t);
-
- SDL_Window* Window = SDL_CreateWindow("penrose", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, current.w, current.h, SDL_WINDOW_OPENGL | SDL_WINDOW_FULLSCREEN);
- SDL_Renderer* Renderer = SDL_CreateRenderer(Window, -1, 0);
-
- while (!quit) {
- SDL_WaitEvent(&event);
+ // An array of 3 vectors which represents 3 vertices
+ static const GLfloat g_vertex_buffer_data[] = {
+ -.5f, -.5f, 0.0f,
+ .5f, -.5f, 0.0f,
+ 0.0f, .5f, 0.0f,
+ };
+
+ //std::vector<triangle> triangles;
+ //t123 t;
+ //SDL_Point points[4] = { {0, 480}, {320, 0}, {640, 480}, {0, 480} };
+ //t.points = points;
+ //triangles.push_back(t);
+
+ // Initialise GLFW
+ glewExperimental = true;
+ if(!glfwInit())
+ {
+ return -1;
+ }
+ glfwWindowHint(GLFW_SAMPLES, 4); // 4x antialiasing
+ glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3); // We want OpenGL 3.3
+ glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
+ glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE); // We don't want the old OpenGL
+
+ // Open a window and create its OpenGL context
+ GLFWwindow* window; // (In the accompanying source code, this variable is global for simplicity)
+ window = glfwCreateWindow(1920, 1080, "penrose", NULL, NULL);
+
+ if(window == NULL) {
+ glfwTerminate();
+ return -1;
+ }
- switch (event.type)
- {
- case SDL_QUIT:
- quit = true;
- break;
- }
+ glfwMakeContextCurrent(window); // Initialize GLEW
+ glewExperimental=true;
- draw(Renderer, triangles);
+ if (glewInit() != GLEW_OK) {
+ return -1;
}
- SDL_DestroyRenderer(Renderer);
- SDL_DestroyWindow(Window);
- SDL_Quit();
+ GLuint VertexArrayID;
+ glGenVertexArrays(1, &VertexArrayID);
+ glBindVertexArray(VertexArrayID);
+
+ glfwSetInputMode(window, GLFW_STICKY_KEYS, GL_TRUE);
+
+ // This will identify our vertex buffer
+ GLuint vertexbuffer;
+ // Generate 1 buffer, put the resulting identifier in vertexbuffer
+ glGenBuffers(1, &vertexbuffer);
+ // The following commands will talk about our 'vertexbuffer' buffer
+ glBindBuffer(GL_ARRAY_BUFFER, vertexbuffer);
+ // Give our vertices to OpenGL.
+ glBufferData(GL_ARRAY_BUFFER, sizeof(g_vertex_buffer_data), g_vertex_buffer_data, GL_STATIC_DRAW);
+
+ GLuint programID = Shader::loadShaders("vertex.vert", "fragment.frag");
+ glUseProgram(programID);
+
+ do{
+ glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+ // 1st attribute buffer : vertices
+ glEnableVertexAttribArray(0);
+ glBindBuffer(GL_ARRAY_BUFFER, vertexbuffer);
+ glVertexAttribPointer(
+ 0, // attribute 0. 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
+ );
+ // Draw the triangle !
+ glDrawArrays(GL_TRIANGLES, 0, 3); // Starting from vertex 0; 3 vertices total -> 1 triangle
+ glDisableVertexAttribArray(0);
+ glfwSwapBuffers(window);
+ glfwPollEvents();
+ }
+ while(glfwGetKey(window, GLFW_KEY_ESCAPE) != GLFW_PRESS && glfwWindowShouldClose(window) == 0);
return 0;
}
diff --git a/shader.cpp b/shader.cpp
@@ -0,0 +1,85 @@
+#include <fstream>
+#include <iostream>
+#include <sstream>
+#include <vector>
+
+#include "shader.hpp"
+
+GLuint Shader::loadShaders(std::string vert_shader, std::string frag_shader) {
+ // Create the shaders
+ GLuint VertexShaderID = glCreateShader(GL_VERTEX_SHADER);
+ GLuint FragmentShaderID = glCreateShader(GL_FRAGMENT_SHADER);
+
+ // Read the Vertex Shader code from the file
+ std::string VertexShaderCode;
+ std::ifstream VertexShaderStream(vert_shader, std::ios::in);
+ if (VertexShaderStream.is_open()) {
+ std::stringstream sstr;
+ sstr << VertexShaderStream.rdbuf();
+ VertexShaderCode = sstr.str();
+ VertexShaderStream.close();
+ }
+
+ // Read the Fragment Shader code from the file
+ std::string FragmentShaderCode;
+ std::ifstream FragmentShaderStream(frag_shader, std::ios::in);
+ if (FragmentShaderStream.is_open()) {
+ std::stringstream sstr;
+ sstr << FragmentShaderStream.rdbuf();
+ FragmentShaderCode = sstr.str();
+ FragmentShaderStream.close();
+ }
+
+ GLint Result = GL_FALSE;
+ int InfoLogLength;
+
+ // Compile Vertex Shader
+ char const * VertexSourcePointer = VertexShaderCode.c_str();
+ glShaderSource(VertexShaderID, 1, &VertexSourcePointer , NULL);
+ glCompileShader(VertexShaderID);
+
+ // Check Vertex Shader
+ glGetShaderiv(VertexShaderID, GL_COMPILE_STATUS, &Result);
+ glGetShaderiv(VertexShaderID, GL_INFO_LOG_LENGTH, &InfoLogLength);
+ if (!InfoLogLength) {
+ std::vector<char> VertexShaderErrorMessage(InfoLogLength + 1);
+ glGetShaderInfoLog(VertexShaderID, InfoLogLength, NULL, &VertexShaderErrorMessage[0]);
+ printf("%sn", &VertexShaderErrorMessage[0]);
+ }
+
+ // Compile Fragment Shader
+ char const * FragmentSourcePointer = FragmentShaderCode.c_str();
+ glShaderSource(FragmentShaderID, 1, &FragmentSourcePointer , NULL);
+ glCompileShader(FragmentShaderID);
+
+ // Check Fragment Shader
+ glGetShaderiv(FragmentShaderID, GL_COMPILE_STATUS, &Result);
+ glGetShaderiv(FragmentShaderID, GL_INFO_LOG_LENGTH, &InfoLogLength);
+ if (!InfoLogLength) {
+ std::vector<char> FragmentShaderErrorMessage(InfoLogLength + 1);
+ glGetShaderInfoLog(FragmentShaderID, InfoLogLength, NULL, &FragmentShaderErrorMessage[0]);
+ printf("%sn", &FragmentShaderErrorMessage[0]);
+ }
+
+ // Link the program
+ GLuint ProgramID = glCreateProgram();
+ glAttachShader(ProgramID, VertexShaderID);
+ glAttachShader(ProgramID, FragmentShaderID);
+ glLinkProgram(ProgramID);
+
+ // Check the program
+ glGetProgramiv(ProgramID, GL_LINK_STATUS, &Result);
+ glGetProgramiv(ProgramID, GL_INFO_LOG_LENGTH, &InfoLogLength);
+ if (!InfoLogLength) {
+ std::vector<char> ProgramErrorMessage(InfoLogLength + 1);
+ glGetProgramInfoLog(ProgramID, InfoLogLength, NULL, &ProgramErrorMessage[0]);
+ printf("%sn", &ProgramErrorMessage[0]);
+ }
+
+ glDetachShader(ProgramID, VertexShaderID);
+ glDetachShader(ProgramID, FragmentShaderID);
+ glDeleteShader(VertexShaderID);
+ glDeleteShader(FragmentShaderID);
+
+ return ProgramID;
+}
diff --git a/shader.hpp b/shader.hpp
@@ -0,0 +1,8 @@
+#include <GL/glew.h>
+
+#include <string>
+
+class Shader {
+public:
+ static GLuint loadShaders(std::string vert_shader, std::string frag_shader);
+};
diff --git a/vertex.vert b/vertex.vert
@@ -0,0 +1,8 @@
+#version 330 core
+
+layout(location = 0) in vec3 vertexPosition_modelspace;
+
+void main() {
+ gl_Position.xyz = vertexPosition_modelspace;
+ gl_Position.w = 1.0;
+}
