glarea 样品
着色器 3.3 + extension.seen 在 radeon hd5500
#version 330
部署的三角形使得法线指向立方体。追踪每个三角形 3 个点的顺序。
//#include <stdio.h>
//#include <string.h>
//#include <iostream>
//#include <glib.h>
#include <gdk/gdkx.h>
#include <epoxy/glx.h>
#include <epoxy/gl.h>
#include <gtk/gtk.h>
#include <glm/glm.hpp>
#include <glm/gtc/matrix_transform.hpp>
#include <glm/gtc/type_ptr.hpp>
const GLchar *vert_src ="\n" \
"#version 330 \n" \
" #extension GL_ARB_explicit_uniform_location : enable \n" \
" \n" \
" out vec4 knn; \n" \
" layout(location = 0) in vec4 in_position; \n" \
" layout(location =10)uniform mat4 projection; \n" \
" out vec4 P; \n" \
"void main() \n" \
"{ \n" \
" gl_Position = projection*in_position; \n" \
"knn=in_position ; \n" \
" \n" \
"// gl_Position = in_position; \n" \
"} \n" ;
const GLchar *frag_src ="\n" \
"#version 330 \n" \
" vec4 b; \n" \
" in vec4 knn; \n" \
"void main (void) \n" \
"{ \n" \
" if(gl_FrontFacing){ \n" \
" b= vec4(gl_FragCoord.x/10.0,gl_FragCoord.y/357.0,gl_FragCoord.z* 0.5,1.0); \n" \
" gl_FragColor = vec4(0.021,-.1777*(knn.y+2)+0.1+1.21557*knn.x+knn.z ,1.215*knn.z+0.583*knn.y +.0357*knn.x+3*b.y, 1.0); \n" \
" } \n" \
"else discard; \n" \
" \n" \
" \n" \
"} \n";
GLfloat t[16]={ 1,0,0,0,
0,1,0,0,
0,0,1,0,
0,0,0,1};
glm::mat4 yt,b;
GLuint gl_vao, gl_buffer, gl_program;
static gboolean realise(GtkGLArea *area, GdkGLContext *context)
{
gtk_gl_area_make_current(GTK_GL_AREA(area));
if (gtk_gl_area_get_error (GTK_GL_AREA(area)) != NULL)
{
printf("failed to initialiize buffers\n");
return false;
}
GLfloat verts[] =
{
+0.7,+0.7,+0.7,
-0.7,0.7, 0.7,
-0.7,+0.7, -0.7,
0.7,+0.7, -0.7,
+0.7,+0.7,+0.7,
-0.7,+0.7, -0.7,
-0.7,-0.7, +0.7,
+0.7,+0.7,+0.7,
-0.7,0.7, 0.7,
+0.7,+0.7,+0.7,
-0.7,-0.7, +0.7,
0.7,-0.7, 0.7,
+0.7,-0.7,-0.7,
-0.7,-0.7,-0.7,
0.7,+0.7, -0.7,
-0.7,+0.7, -0.7,
0.7,+0.7, -0.7,
-0.7,-0.7, -0.7,
-0.7,-0.7, +0.7,
-0.7,-0.7, -0.7,
0.7,-0.7, 0.7,
+0.7,-0.7, -0.7,
0.7,-0.7, 0.7,
-0.7,-0.7, -0.7,
0.7,+0.7, -0.7,
+0.7,+0.7,+0.7,
+0.7,-0.7, -0.7,
0.7,-0.7, -0.7,
+0.7,+0.7,+0.7,
0.7,-0.7, 0.7,
-0.7,-0.7, -0.7,
-0.7,0.7, 0.7,
-0.7,+0.7, -0.7,
-0.7,-0.7, +0.7,
-0.7,0.7, 0.7,
-0.7,-0.7, -0.7
};
b=glm::lookAt(glm::vec3(1.75,-2.38,1.4444), glm::vec3( 0., 0., 0.),glm::vec3( 0.,0.2,-00.));
yt=glm::perspective(45., 1., 1.2, 300.);
b=yt*b*glm::mat4(1.);
//b=glm::lookAt(glm::vec3(0., 0.,-1.),glm::vec3( 0., 0., 0.),glm::vec3( 0.,025.,-1.));
//yt=yt*b;
GLuint frag_shader, vert_shader;
frag_shader = glCreateShader(GL_FRAGMENT_SHADER);
vert_shader = glCreateShader(GL_VERTEX_SHADER);
glShaderSource(frag_shader, 1, &frag_src, NULL);
glShaderSource(vert_shader, 1, &vert_src, NULL);
glCompileShader(frag_shader);
glCompileShader(vert_shader);
gl_program = glCreateProgram();
glAttachShader(gl_program, frag_shader);
glAttachShader(gl_program, vert_shader);
glLinkProgram(gl_program);
// glUniformMatrix4fv(1, 1, 0, glm::value_ptr(b));
glGenVertexArrays(1, &gl_vao);
glBindVertexArray(gl_vao);
glGenBuffers(1, &gl_buffer);
glBindBuffer(GL_ARRAY_BUFFER, gl_buffer);
glBufferData(GL_ARRAY_BUFFER, sizeof(verts), verts, GL_STATIC_DRAW);
glEnableVertexAttribArray(0);
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 0, (void*)0);
glBindVertexArray(0);
return TRUE;
}
static gboolean render(GtkGLArea *area, GdkGLContext *context)
{
glEnable(GL_DEPTH_TEST);
glEnable(GL_BLEND);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glClearColor(0.0, 0.0, 0.0, 1.0);
glUseProgram(gl_program);
glUniformMatrix4fv(10, 1, 0, &b[0][0]);
glBindVertexArray(gl_vao);
glDrawArrays(GL_TRIANGLES,0,36 );
glBindVertexArray (0);
glUseProgram (0);
glFlush();
return TRUE;
}
int main(int argc, char** argv)
{
gtk_init(&argc, &argv);
GtkWidget *window = gtk_window_new(GTK_WINDOW_TOPLEVEL),
*gl_area = gtk_gl_area_new();
g_signal_connect(window, "delete-event", G_CALLBACK(gtk_main_quit), NULL);
g_signal_connect(gl_area, "realize", G_CALLBACK(realise), NULL);
g_signal_connect(gl_area, "render", G_CALLBACK(render), NULL);
gtk_container_add(GTK_CONTAINER(window), gl_area);
gtk_widget_show_all(window);
gtk_main();
return 0;
}