Convert tearing test to GL2

This commit is contained in:
Camilla Berglund 2016-08-22 00:54:05 +02:00
parent f86edf8d3c
commit fbb2d5e10d

View File

@ -35,8 +35,34 @@
#include <stdlib.h>
#include <math.h>
#include "linmath.h"
#include "getopt.h"
static const struct
{
float x, y;
} vertices[4] =
{
{ -0.25f, -1.f },
{ 0.25f, -1.f },
{ 0.25f, 1.f },
{ -0.25f, 1.f }
};
static const char* vertex_shader_text =
"uniform mat4 MVP;\n"
"attribute vec2 vPos;\n"
"void main()\n"
"{\n"
" gl_Position = MVP * vec4(vPos, 0.0, 1.0);\n"
"}\n";
static const char* fragment_shader_text =
"void main()\n"
"{\n"
" gl_FragColor = vec4(1.0);\n"
"}\n";
static int swap_tear;
static int swap_interval;
static double frame_rate;
@ -122,6 +148,8 @@ int main(int argc, char** argv)
int fullscreen = GLFW_FALSE;
GLFWmonitor* monitor = NULL;
GLFWwindow* window;
GLuint vertex_buffer, vertex_shader, fragment_shader, program;
GLint mvp_location, vpos_location, vcol_location;
while ((ch = getopt(argc, argv, "fh")) != -1)
{
@ -163,6 +191,9 @@ int main(int argc, char** argv)
height = 480;
}
glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 2);
glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 0);
window = glfwCreateWindow(width, height, "", monitor, NULL);
if (!window)
{
@ -182,16 +213,44 @@ int main(int argc, char** argv)
glfwSetFramebufferSizeCallback(window, framebuffer_size_callback);
glfwSetKeyCallback(window, key_callback);
glMatrixMode(GL_PROJECTION);
glOrtho(-1.f, 1.f, -1.f, 1.f, 1.f, -1.f);
glMatrixMode(GL_MODELVIEW);
glGenBuffers(1, &vertex_buffer);
glBindBuffer(GL_ARRAY_BUFFER, vertex_buffer);
glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
vertex_shader = glCreateShader(GL_VERTEX_SHADER);
glShaderSource(vertex_shader, 1, &vertex_shader_text, NULL);
glCompileShader(vertex_shader);
fragment_shader = glCreateShader(GL_FRAGMENT_SHADER);
glShaderSource(fragment_shader, 1, &fragment_shader_text, NULL);
glCompileShader(fragment_shader);
program = glCreateProgram();
glAttachShader(program, vertex_shader);
glAttachShader(program, fragment_shader);
glLinkProgram(program);
mvp_location = glGetUniformLocation(program, "MVP");
vpos_location = glGetAttribLocation(program, "vPos");
glEnableVertexAttribArray(vpos_location);
glVertexAttribPointer(vpos_location, 2, GL_FLOAT, GL_FALSE,
sizeof(vertices[0]), (void*) 0);
while (!glfwWindowShouldClose(window))
{
mat4x4 m, p, mvp;
float position = cosf((float) glfwGetTime() * 4.f) * 0.75f;
glClear(GL_COLOR_BUFFER_BIT);
position = cosf((float) glfwGetTime() * 4.f) * 0.75f;
glRectf(position - 0.25f, -1.f, position + 0.25f, 1.f);
mat4x4_ortho(p, -1.f, 1.f, -1.f, 1.f, 0.f, 1.f);
mat4x4_translate(m, position, 0.f, 0.f);
mat4x4_mul(mvp, p, m);
glUseProgram(program);
glUniformMatrix4fv(mvp_location, 1, GL_FALSE, (const GLfloat*) mvp);
glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
glfwSwapBuffers(window);
glfwPollEvents();