gltut / Tut 05 Objects in Depth / DepthBuffer.cpp

Jason McKesson ff914d3 



Jason McKesson da7c819 

Jason McKesson 74c4b9b 
Jason McKesson ff914d3 











































































































































































































Jason McKesson c689e4d 



Jason McKesson ff914d3 








Jason McKesson 8618f34 
Jason McKesson 5cddc8c 
Jason McKesson ff914d3 

























































Jason McKesson f314aea 
#include <string>
#include <vector>
#include <math.h>
#include <stdio.h>
#include <string.h>
#include <glload/gl_3_3.h>
#include <GL/freeglut.h>
#include "../framework/framework.h"

#define ARRAY_COUNT( array ) (sizeof( array ) / (sizeof( array[0] ) * (sizeof( array ) != sizeof(void*) || sizeof( array[0] ) <= sizeof(void*))))

GLuint theProgram;

GLuint offsetUniform;
GLuint perspectiveMatrixUnif;

float perspectiveMatrix[16];
const float fFrustumScale = 1.0f;

void InitializeProgram()
{
	std::vector<GLuint> shaderList;

	shaderList.push_back(Framework::LoadShader(GL_VERTEX_SHADER, "Standard.vert"));
	shaderList.push_back(Framework::LoadShader(GL_FRAGMENT_SHADER, "Standard.frag"));

	theProgram = Framework::CreateProgram(shaderList);

	offsetUniform = glGetUniformLocation(theProgram, "offset");

	perspectiveMatrixUnif = glGetUniformLocation(theProgram, "perspectiveMatrix");

	float fzNear = 1.0f; float fzFar = 3.0f;

	memset(perspectiveMatrix, 0, sizeof(float) * 16);

	perspectiveMatrix[0] = fFrustumScale;
	perspectiveMatrix[5] = fFrustumScale;
	perspectiveMatrix[10] = (fzFar + fzNear) / (fzNear - fzFar);
	perspectiveMatrix[14] = (2 * fzFar * fzNear) / (fzNear - fzFar);
	perspectiveMatrix[11] = -1.0f;

	glUseProgram(theProgram);
	glUniformMatrix4fv(perspectiveMatrixUnif, 1, GL_FALSE, perspectiveMatrix);
	glUseProgram(0);
}

const int numberOfVertices = 36;

#define RIGHT_EXTENT 0.8f
#define LEFT_EXTENT -RIGHT_EXTENT
#define TOP_EXTENT 0.20f
#define MIDDLE_EXTENT 0.0f
#define BOTTOM_EXTENT -TOP_EXTENT
#define FRONT_EXTENT -1.25f
#define REAR_EXTENT -1.75f

#define GREEN_COLOR 0.75f, 0.75f, 1.0f, 1.0f
#define BLUE_COLOR 	0.0f, 0.5f, 0.0f, 1.0f
#define RED_COLOR 1.0f, 0.0f, 0.0f, 1.0f
#define GREY_COLOR 0.8f, 0.8f, 0.8f, 1.0f
#define BROWN_COLOR 0.5f, 0.5f, 0.0f, 1.0f

const float vertexData[] = {
	//Object 1 positions
	LEFT_EXTENT,	TOP_EXTENT,		REAR_EXTENT,
	LEFT_EXTENT,	MIDDLE_EXTENT,	FRONT_EXTENT,
	RIGHT_EXTENT,	MIDDLE_EXTENT,	FRONT_EXTENT,
	RIGHT_EXTENT,	TOP_EXTENT,		REAR_EXTENT,

	LEFT_EXTENT,	BOTTOM_EXTENT,	REAR_EXTENT,
	LEFT_EXTENT,	MIDDLE_EXTENT,	FRONT_EXTENT,
	RIGHT_EXTENT,	MIDDLE_EXTENT,	FRONT_EXTENT,
	RIGHT_EXTENT,	BOTTOM_EXTENT,	REAR_EXTENT,

	LEFT_EXTENT,	TOP_EXTENT,		REAR_EXTENT,
	LEFT_EXTENT,	MIDDLE_EXTENT,	FRONT_EXTENT,
	LEFT_EXTENT,	BOTTOM_EXTENT,	REAR_EXTENT,

	RIGHT_EXTENT,	TOP_EXTENT,		REAR_EXTENT,
	RIGHT_EXTENT,	MIDDLE_EXTENT,	FRONT_EXTENT,
	RIGHT_EXTENT,	BOTTOM_EXTENT,	REAR_EXTENT,

	LEFT_EXTENT,	BOTTOM_EXTENT,	REAR_EXTENT,
	LEFT_EXTENT,	TOP_EXTENT,		REAR_EXTENT,
	RIGHT_EXTENT,	TOP_EXTENT,		REAR_EXTENT,
	RIGHT_EXTENT,	BOTTOM_EXTENT,	REAR_EXTENT,

	//	0, 2, 1,
	//	3, 2, 0,

	//Object 2 positions
	TOP_EXTENT,		RIGHT_EXTENT,	REAR_EXTENT,
	MIDDLE_EXTENT,	RIGHT_EXTENT,	FRONT_EXTENT,
	MIDDLE_EXTENT,	LEFT_EXTENT,	FRONT_EXTENT,
	TOP_EXTENT,		LEFT_EXTENT,	REAR_EXTENT,

	BOTTOM_EXTENT,	RIGHT_EXTENT,	REAR_EXTENT,
	MIDDLE_EXTENT,	RIGHT_EXTENT,	FRONT_EXTENT,
	MIDDLE_EXTENT,	LEFT_EXTENT,	FRONT_EXTENT,
	BOTTOM_EXTENT,	LEFT_EXTENT,	REAR_EXTENT,

	TOP_EXTENT,		RIGHT_EXTENT,	REAR_EXTENT,
	MIDDLE_EXTENT,	RIGHT_EXTENT,	FRONT_EXTENT,
	BOTTOM_EXTENT,	RIGHT_EXTENT,	REAR_EXTENT,

	TOP_EXTENT,		LEFT_EXTENT,	REAR_EXTENT,
	MIDDLE_EXTENT,	LEFT_EXTENT,	FRONT_EXTENT,
	BOTTOM_EXTENT,	LEFT_EXTENT,	REAR_EXTENT,

	BOTTOM_EXTENT,	RIGHT_EXTENT,	REAR_EXTENT,
	TOP_EXTENT,		RIGHT_EXTENT,	REAR_EXTENT,
	TOP_EXTENT,		LEFT_EXTENT,	REAR_EXTENT,
	BOTTOM_EXTENT,	LEFT_EXTENT,	REAR_EXTENT,

	//Object 1 colors
	GREEN_COLOR,
	GREEN_COLOR,
	GREEN_COLOR,
	GREEN_COLOR,

	BLUE_COLOR,
	BLUE_COLOR,
	BLUE_COLOR,
	BLUE_COLOR,

	RED_COLOR,
	RED_COLOR,
	RED_COLOR,

	GREY_COLOR,
	GREY_COLOR,
	GREY_COLOR,

	BROWN_COLOR,
	BROWN_COLOR,
	BROWN_COLOR,
	BROWN_COLOR,

	//Object 2 colors
	RED_COLOR,
	RED_COLOR,
	RED_COLOR,
	RED_COLOR,

	BROWN_COLOR,
	BROWN_COLOR,
	BROWN_COLOR,
	BROWN_COLOR,

	BLUE_COLOR,
	BLUE_COLOR,
	BLUE_COLOR,

	GREEN_COLOR,
	GREEN_COLOR,
	GREEN_COLOR,

	GREY_COLOR,
	GREY_COLOR,
	GREY_COLOR,
	GREY_COLOR,
};

const GLshort indexData[] =
{
	0, 2, 1,
	3, 2, 0,

	4, 5, 6,
	6, 7, 4,

	8, 9, 10,
	11, 13, 12,

	14, 16, 15,
	17, 16, 14,
};

GLuint vertexBufferObject;
GLuint indexBufferObject;
GLuint vao;


void InitializeVertexBuffer()
{
	glGenBuffers(1, &vertexBufferObject);

	glBindBuffer(GL_ARRAY_BUFFER, vertexBufferObject);
	glBufferData(GL_ARRAY_BUFFER, sizeof(vertexData), vertexData, GL_STATIC_DRAW);
	glBindBuffer(GL_ARRAY_BUFFER, 0);

	glGenBuffers(1, &indexBufferObject);

	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, indexBufferObject);
	glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(indexData), indexData, GL_STATIC_DRAW);
	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
}

//Called after the window and OpenGL are initialized. Called exactly once, before the main loop.
void init()
{
	InitializeProgram();
	InitializeVertexBuffer();

	glGenVertexArrays(1, &vao);
	glBindVertexArray(vao);

	size_t colorDataOffset = sizeof(float) * 3 * numberOfVertices;
	glBindBuffer(GL_ARRAY_BUFFER, vertexBufferObject);
	glEnableVertexAttribArray(0);
	glEnableVertexAttribArray(1);
	glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 0, 0);
	glVertexAttribPointer(1, 4, GL_FLOAT, GL_FALSE, 0, (void*)colorDataOffset);
	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, indexBufferObject);

	glBindVertexArray(0);

	glEnable(GL_CULL_FACE);
	glCullFace(GL_BACK);
	glFrontFace(GL_CW);

	glEnable(GL_DEPTH_TEST);
	glDepthMask(GL_TRUE);
	glDepthFunc(GL_LEQUAL);
	glDepthRange(0.0f, 1.0f);
}

//Called to update the display.
//You should call glutSwapBuffers after all of your rendering to display what you rendered.
//If you need continuous updates of the screen, call glutPostRedisplay() at the end of the function.
void display()
{
	glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
	glClearDepth(1.0f);
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

	glUseProgram(theProgram);

	glBindVertexArray(vao);

	glUniform3f(offsetUniform, 0.0f, 0.0f, 0.0f);
	glDrawElements(GL_TRIANGLES, ARRAY_COUNT(indexData), GL_UNSIGNED_SHORT, 0);

	glUniform3f(offsetUniform, 0.0f, 0.0f, -1.0f);
	glDrawElementsBaseVertex(GL_TRIANGLES, ARRAY_COUNT(indexData),
		GL_UNSIGNED_SHORT, 0, numberOfVertices / 2);

	glBindVertexArray(0);
	glUseProgram(0);

	glutSwapBuffers();
}

//Called whenever the window is resized. The new window size is given, in pixels.
//This is an opportunity to call glViewport or glScissor to keep up with the change in size.
void reshape (int w, int h)
{
	perspectiveMatrix[0] = fFrustumScale * (h / (float)w);
	perspectiveMatrix[5] = fFrustumScale;

	glUseProgram(theProgram);
	glUniformMatrix4fv(perspectiveMatrixUnif, 1, GL_FALSE, perspectiveMatrix);
	glUseProgram(0);

	glViewport(0, 0, (GLsizei) w, (GLsizei) h);
}

//Called whenever a key on the keyboard was pressed.
//The key is given by the ''key'' parameter, which is in ASCII.
//It's often a good idea to have the escape key (ASCII value 27) call glutLeaveMainLoop() to 
//exit the program.
void keyboard(unsigned char key, int x, int y)
{
	switch (key)
	{
	case 27:
		glutLeaveMainLoop();
		break;
	}
}


unsigned int defaults(unsigned int displayMode, int &width, int &height) {return displayMode;}
Tip: Filter by directory path e.g. /media app.js to search for public/media/app.js.
Tip: Use camelCasing e.g. ProjME to search for ProjectModifiedEvent.java.
Tip: Filter by extension type e.g. /repo .js to search for all .js files in the /repo directory.
Tip: Separate your search with spaces e.g. /ssh pom.xml to search for src/ssh/pom.xml.
Tip: Use ↑ and ↓ arrow keys to navigate and return to view the file.
Tip: You can also navigate files with Ctrl+j (next) and Ctrl+k (previous) and view the file with Ctrl+o.
Tip: You can also navigate files with Alt+j (next) and Alt+k (previous) and view the file with Alt+o.