started with coordinate system section

src/Engine/main.cpp

@@ -11,7 +11,7 @@
 #include "util/stb_image.h"
 
 // Continue: https://learnopengl.com/Getting-started/Coordinate-Systems
-// Chapter: not started
+// Chapter: More Cubes!
 //
 // TODO: look at project->properties->VC++ Directories-> change everything to the Environment var
 // For the "real" Nebulix Engine setup everything so it can be compiled/used with VSCode/CLion and not just VS (so basically having an "external" folder which has open gl, GLAD, etc. in it or something like this)
@@ -27,6 +27,8 @@
 
 #define WINDOW_WIDTH 800
 #define WINDOW_HEIGHT 600
+typedef glm::mat4 mat4;
+typedef glm::vec3 vec3;
 
 
 void OnWindowResize(GLFWwindow* window, int width, int height)
@@ -68,16 +70,69 @@ int main()
 	OnWindowResize(window, WINDOW_WIDTH, WINDOW_HEIGHT);
 	glfwSetFramebufferSizeCallback(window, OnWindowResize);
 
-	GLfloat vertices[] = { // world coordinate, colour, uv coordinates
+	float vertices[] = { // object coordinates, uv-coordinates
-	  0.5f,  0.5f, 0.0f,   1.0f, 0.0f, 0.0f,   1.0f, 1.0f,  // top right
+	-0.5f, -0.5f, -0.5f,  0.0f, 0.0f,
-	  0.5f, -0.5f, 0.0f,   0.0f, 1.0f, 0.0f,   1.0f, 0.0f,  // bottom right
+	 0.5f, -0.5f, -0.5f,  1.0f, 0.0f,
-	 -0.5f, -0.5f, 0.0f,   0.0f, 0.0f, 1.0f,   0.0f, 0.0f,  // bottom left
+	 0.5f,  0.5f, -0.5f,  1.0f, 1.0f,
-	 -0.5f,  0.5f, 0.0f,   1.0f, 0.0f, 0.0f,   0.0f, 1.0f   // top left 
+	 0.5f,  0.5f, -0.5f,  1.0f, 1.0f,
+	-0.5f,  0.5f, -0.5f,  0.0f, 1.0f,
+	-0.5f, -0.5f, -0.5f,  0.0f, 0.0f,
+
+	-0.5f, -0.5f,  0.5f,  0.0f, 0.0f,
+	 0.5f, -0.5f,  0.5f,  1.0f, 0.0f,
+	 0.5f,  0.5f,  0.5f,  1.0f, 1.0f,
+	 0.5f,  0.5f,  0.5f,  1.0f, 1.0f,
+	-0.5f,  0.5f,  0.5f,  0.0f, 1.0f,
+	-0.5f, -0.5f,  0.5f,  0.0f, 0.0f,
+
+	-0.5f,  0.5f,  0.5f,  1.0f, 0.0f,
+	-0.5f,  0.5f, -0.5f,  1.0f, 1.0f,
+	-0.5f, -0.5f, -0.5f,  0.0f, 1.0f,
+	-0.5f, -0.5f, -0.5f,  0.0f, 1.0f,
+	-0.5f, -0.5f,  0.5f,  0.0f, 0.0f,
+	-0.5f,  0.5f,  0.5f,  1.0f, 0.0f,
+
+	 0.5f,  0.5f,  0.5f,  1.0f, 0.0f,
+	 0.5f,  0.5f, -0.5f,  1.0f, 1.0f,
+	 0.5f, -0.5f, -0.5f,  0.0f, 1.0f,
+	 0.5f, -0.5f, -0.5f,  0.0f, 1.0f,
+	 0.5f, -0.5f,  0.5f,  0.0f, 0.0f,
+	 0.5f,  0.5f,  0.5f,  1.0f, 0.0f,
+
+	-0.5f, -0.5f, -0.5f,  0.0f, 1.0f,
+	 0.5f, -0.5f, -0.5f,  1.0f, 1.0f,
+	 0.5f, -0.5f,  0.5f,  1.0f, 0.0f,
+	 0.5f, -0.5f,  0.5f,  1.0f, 0.0f,
+	-0.5f, -0.5f,  0.5f,  0.0f, 0.0f,
+	-0.5f, -0.5f, -0.5f,  0.0f, 1.0f,
+
+	-0.5f,  0.5f, -0.5f,  0.0f, 1.0f,
+	 0.5f,  0.5f, -0.5f,  1.0f, 1.0f,
+	 0.5f,  0.5f,  0.5f,  1.0f, 0.0f,
+	 0.5f,  0.5f,  0.5f,  1.0f, 0.0f,
+	-0.5f,  0.5f,  0.5f,  0.0f, 0.0f,
+	-0.5f,  0.5f, -0.5f,  0.0f, 1.0f
 	};
+
 	GLuint faces[]{
 		0, 1, 3,
-		1, 2, 3
+		1, 2, 3,
-	};
+
+		4, 5, 6,
+		5, 6, 7,
+
+		8, 9, 10,
+		9, 10, 11,
+
+		12, 13, 14,
+		13, 14, 15,
+
+		16, 17, 18,
+		17, 18, 19,
+
+		20, 21, 22,
+		21, 22, 23
+	}; // 23
 
 	// VBO == all verticies; EBO == connection of vertices (faces) and is optional although it is a bit more efficient than using VBOs; 
 	// VAO == collection of VBOs/EBOs used for rendering
@@ -95,13 +150,10 @@ int main()
 	glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(faces), faces, GL_STATIC_DRAW);
 
 	// position attribute
-	glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)0);
+	glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 5 * sizeof(float), (void*)0);
 	glEnableVertexAttribArray(0);
-	// colour (or more general, the second vertex Attribute)
-	glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(3 * sizeof(float)));
-	glEnableVertexAttribArray(1);
 	// uv-coordinates (or more general the third vertex attribute)
-	glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(6 * sizeof(float)));
+	glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 5 * sizeof(float), (void*)(3 * sizeof(float)));
 	glEnableVertexAttribArray(2);
 	// I could unbind the VAO, but this is usually not needed because when creating a new VAO we need to bind that to change it anyway, so there shouldn't be a problem
 
@@ -156,27 +208,32 @@ int main()
 	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); // use nearest neighbour when zooming out
 	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); // use bilinear when zooming in
 
+	mat4 modelMatrix = mat4(1.0f);
+	modelMatrix = glm::rotate(modelMatrix, glm::radians(-55.0f), vec3(1.0f, 0, 0));
+	mat4 viewMatrix = mat4(1.0f);
+	viewMatrix = glm::translate(viewMatrix, vec3(0, 0, -3.0f));
+	mat4 projectionMatrix = glm::perspective(glm::radians(45.0f), 800.0f / 600.0f, 0.1f, 100.0f);
 
+	glEnable(GL_DEPTH_TEST);
+	float timeLastFrame = glfwGetTime();
 	// main loop
 	while(!glfwWindowShouldClose(window))
 	{
 		glClearColor(0.2f, 0.3f, 0.3f, 1.0f);
-		glClear(GL_COLOR_BUFFER_BIT);
+		glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 
 		ProcessInput(window);
+		
+		float time = glfwGetTime();
 
-		glm::mat4 transform = glm::mat4(1.0f);
+		modelMatrix = glm::rotate(modelMatrix, time * (time - timeLastFrame) + 0.001f * glm::radians(50.0f), glm::vec3(0.5f, 1.0f, 0.0f));
-		transform = glm::rotate(transform, (float)glfwGetTime(), glm::vec3(0, 0, 1.0f));
-		transform = glm::translate(transform, glm::vec3(glm::sin((float)glfwGetTime()), 0, 0));
-		//transform = glm::scale(transform, glm::vec3(glm::sin((float)glfwGetTime())));
 
 		shader->Use();
 		shader->SetInt("ourTexture1", 0);
 		shader->SetInt("ourTexture2", 1);
-		shader->SetMatrix("transform", transform);
+		shader->SetMatrix("modelMatrix", modelMatrix);
-		//float time = glfwGetTime();
+		shader->SetMatrix("viewMatrix", viewMatrix);
-		//float greenValue = (sin(time) / 2.0f) + 0.5f;
+		shader->SetMatrix("projectionMatrix", projectionMatrix);
-		//shader->setFloat("ourColour", 0.0f, greenValue, 0.0f, 0.0f);
 
 		glActiveTexture(GL_TEXTURE0); // before binding texture, activate correct textre Unit (some drivers might show nothing if this is omitted)
 		glBindTexture(GL_TEXTURE_2D, textureID_container);
@@ -184,10 +241,12 @@ int main()
 		glBindTexture(GL_TEXTURE_2D, textureID_face);
 		
 		glBindVertexArray(vertexArrayObject);
-		glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0);
+		//glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0); // for EBOs
+		glDrawArrays(GL_TRIANGLES, 0, 36); // for VAOs
 
 		glfwSwapBuffers(window);
 		glfwPollEvents();
+		timeLastFrame = glfwGetTime();
 	}
 
 	// optional, as we are at the end of the program.

src/Engine/shaders/default/default.vert

@@ -1,16 +1,22 @@
 #version 330 core
 layout (location = 0) in vec3 aPos;
-layout (location = 1) in vec3 aColour;
+//layout (location = 1) in vec3 aColour;
 layout (location = 2) in vec2 aTexCoord;
 
 out vec3 ourColour;
 out vec2 texCoord;
 
-uniform mat4 transform;
+uniform mat4 modelMatrix;
+uniform mat4 viewMatrix;
+uniform mat4 projectionMatrix;
+
+//uniform mat4 transform;
 
 void main()
 {
-	gl_Position = transform * vec4(aPos, 1.0);
+	// note that we read the multiplication from right to left
-	ourColour = aColour;
+    gl_Position = projectionMatrix * viewMatrix * modelMatrix * vec4(aPos, 1.0);
+	//gl_Position = transform * vec4(aPos, 1.0);
+	ourColour = vec3(1.0);
 	texCoord = aTexCoord;
 }