c++openglshaderfragment-shadervertex-shader
Opengl Sierpinski Shader based C code in Visual Studio2012 & 2010
I'm doing my first steps in OpenGl Shader base programming and computer graphics. I'm trying the following example, but when I try to compile the project I got the following error:
fragment shader failed to link. vertex shader failed to link. ERROR: Not all shaders has valid object code
i tried running the program in Visual Studio 2012 and 2010. glut library version is 3.7 and glew library version is 1.10.0. what is the problem?
.cpp Program
#include <stdio.h>
#include <stdlib.h>
#include <glew.h>
#include <glut.h>
#include <gl.h>
#pragma comment(lib,"glew32.lib")
#define NoP 50000
GLuint InitShader(char *, char *);
void mydisplay();
struct points
{ GLfloat x,y,z;
};
void init();
void Sierpinski(points Num[]);
int main(int argc, char** argv)
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_RGB | GLUT_SINGLE|GLUT_DEPTH);
glutInitWindowSize(600, 600);
glutInitWindowPosition(0,0);
glutCreateWindow("Sierpinski 3D");
glewInit();
init();
glEnable(GL_DEPTH_TEST);
glutDisplayFunc(mydisplay);
glutMainLoop();
}
void init()
{
points Num[NoP];
Sierpinski(Num);
glClearColor(1.0f, 1.0f, 1.0f, 0.0f);//set the color for clearing the display
glPointSize(2); // set the point size
// Creating a program object containing shader files
GLuint program;
program = InitShader("vshader.glsl","fshader.glsl");
glUseProgram(program);
//Creating a buffer object containing Sirepinski verteces data
GLuint buffer;
glGenBuffers(1, &buffer);
glBindBuffer(GL_ARRAY_BUFFER, buffer);
glBufferData(GL_ARRAY_BUFFER, sizeof(Num), Num, GL_STATIC_DRAW);
//Make a conncetion between data in object buffer and "vPosition in vertex shader
GLuint location = glGetAttribLocation(program, "vPosition");
glEnableVertexAttribArray ( location );
glVertexAttribPointer( location, 3, GL_FLOAT, GL_FALSE,0, 0);//BUFFER_OFFSET(0));
}
void mydisplay()
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); //the clear call will affect the color buffer
glDrawArrays(GL_POINTS,0,NoP);//Rendering verteces data
glFlush(); //Empty all commands buffer, causing all issued commands to be executed as quickly as they are accepted by the actual rendering engine
}
static char * ReadShaderSource(char * ShaderFile)
{
FILE *fp;
fp = fopen(ShaderFile,"rt");
if (!fp) return NULL;
long size=0;
while (!feof(fp))
{
fgetc (fp);
size++;
}
size--;//EOF should not be counted
fseek(fp, 0, SEEK_SET);
char * buf= new char[size + 1];
fread(buf, 1, size,fp);
buf[size]=0;// string is NULL terminated
fclose(fp);
return buf;
}
GLuint InitShader(char * vShaderFile, char * fShaderFile)
{
char * svs, * sfs;
GLuint program, VertexShader, FragmentShader;
program = glCreateProgram();
VertexShader = glCreateShader(GL_VERTEX_SHADER);
svs=ReadShaderSource(vShaderFile);
glShaderSource(VertexShader,1,(const GLchar **)&svs,NULL);
glCompileShader(VertexShader);
// reading GLSL compiler error messages for vertex shader
GLint compiled;
glGetShaderiv(VertexShader, GL_COMPILE_STATUS, &compiled);
if(!compiled)
{ printf("/n failed to compile");
GLint logSize;
glGetShaderiv(VertexShader, GL_INFO_LOG_LENGTH,&logSize);
char * logMsg = new char[logSize];
glGetShaderInfoLog(VertexShader, logSize, NULL, logMsg);
printf("\n %s",logMsg);
delete [] logMsg;
getchar();
exit(EXIT_FAILURE);
}
FragmentShader = glCreateShader(GL_FRAGMENT_SHADER);
sfs = ReadShaderSource(fShaderFile);
glShaderSource(FragmentShader, 1, (const GLchar **)&sfs, NULL);
glCompileShader(FragmentShader);
// reading GLSL compiler error messages for fragment shader
glGetShaderiv(FragmentShader, GL_COMPILE_STATUS, &compiled);
if(!compiled)
{ printf("\n failed to compile");
GLint logSize2;
glGetShaderiv(FragmentShader, GL_INFO_LOG_LENGTH,&logSize2);
char * logMsg2 = new char[logSize2];
glGetShaderInfoLog(FragmentShader, logSize2, NULL, logMsg2);
printf("\n %s",logMsg2);
delete [] logMsg2;
getchar();
exit(EXIT_FAILURE);
}
glAttachShader(program,VertexShader);
glAttachShader(program, FragmentShader);
glLinkProgram(program);
// reading GLSL linker error messages for program object
GLint linked;
glGetProgramiv(program, GL_LINK_STATUS, &linked);
if(!linked)
{ printf("/n failed to link");
GLint logSize;
glGetProgramiv(program, GL_INFO_LOG_LENGTH,&logSize);
char * logMsg = new char[logSize];
glGetProgramInfoLog(program, logSize, NULL, logMsg);
printf("\n %s",logMsg);
delete [] logMsg;
getchar();
exit(EXIT_FAILURE);
}
glUseProgram(program);
return program;
}
void Sierpinski(points Num[])
{
int j;
points Vertices[4]={{-1.0,-1.0, -1.0},{1.0,-1.0,-1.0},{0.0,1.0,-1.0},{0.0,0.0,1.0}};
Num[0].x = 0;
Num[0].y = 0;
Num[0].z = 0;
for(int i=1;i<NoP;i++)
{
j = rand() % 4;
Num[i].x = (Vertices[j].x + Num[i - 1].x)/2;
Num[i].y = (Vertices[j].y + Num[i - 1].y)/2;
Num[i].z = (Vertices[j].z + Num[i - 1].z)/2;
}
}
vshader.glsl
#version 130
in vec4 vPosition;
out vec4 color;
void main()
{
gl_Position = vPosition;
color = vPosition;
}
fshader.glsl
#version 130
in vec4 color;
void main()
{
gl_FragColor = vec4((1.0 + color.xyz)/2.0,1.0);
}
Solution
Seems to work fine:
#include <GL/glew.h>
#include <GL/glut.h>
#include <iostream>
void CheckStatus( GLuint obj )
{
GLint status = GL_FALSE;
if( glIsShader(obj) ) glGetShaderiv( obj, GL_COMPILE_STATUS, &status );
if( glIsProgram(obj) ) glGetProgramiv( obj, GL_LINK_STATUS, &status );
if( status == GL_TRUE ) return;
GLchar log[ 1 << 17 ] = { 0 };
if( glIsShader(obj) ) glGetShaderInfoLog( obj, sizeof(log), NULL, log );
if( glIsProgram(obj) ) glGetProgramInfoLog( obj, sizeof(log), NULL, log );
std::cerr << log << std::endl;
exit( -1 );
}
void AttachShader( GLuint program, GLenum type, const char* src )
{
GLuint shader = glCreateShader( type );
glShaderSource( shader, 1, &src, NULL );
glCompileShader( shader );
CheckStatus( shader );
glAttachShader( program, shader );
glDeleteShader( shader );
}
GLuint LoadProgram( const char* vert, const char* geom, const char* frag )
{
GLuint prog = glCreateProgram();
if( vert ) AttachShader( prog, GL_VERTEX_SHADER, vert );
if( geom ) AttachShader( prog, GL_GEOMETRY_SHADER, geom );
if( frag ) AttachShader( prog, GL_FRAGMENT_SHADER, frag );
glLinkProgram( prog );
CheckStatus( prog );
return prog;
}
#define GLSL(version, shader) "#version " #version "\n" #shader
const char* vert = GLSL
(
130,
in vec4 vPosition;
out vec4 color;
void main()
{
gl_Position = vPosition;
color = vPosition;
}
);
const char* frag = GLSL
(
130,
precision mediump float;
in vec4 color;
void main()
{
gl_FragColor = vec4((1.0 + color.xyz)/2.0,1.0);
}
);
#define NoP 50000
struct points
{
GLfloat x,y,z;
};
void Sierpinski(points Num[])
{
int j;
points Vertices[4]={{-1.0,-1.0, -1.0},{1.0,-1.0,-1.0},{0.0,1.0,-1.0},{0.0,0.0,1.0}};
Num[0].x = 0;
Num[0].y = 0;
Num[0].z = 0;
for(int i=1;i<NoP;i++)
{
j = rand() % 4;
Num[i].x = (Vertices[j].x + Num[i - 1].x)/2;
Num[i].y = (Vertices[j].y + Num[i - 1].y)/2;
Num[i].z = (Vertices[j].z + Num[i - 1].z)/2;
}
}
void init()
{
points Num[NoP];
Sierpinski(Num);
GLuint program = LoadProgram( vert, NULL, frag );
glUseProgram(program);
//Creating a buffer object containing Sirepinski verteces data
GLuint buffer;
glGenBuffers(1, &buffer);
glBindBuffer(GL_ARRAY_BUFFER, buffer);
glBufferData(GL_ARRAY_BUFFER, sizeof(Num), Num, GL_STATIC_DRAW);
//Make a conncetion between data in object buffer and "vPosition in vertex shader
GLuint location = glGetAttribLocation(program, "vPosition");
glEnableVertexAttribArray ( location );
glVertexAttribPointer( location, 3, GL_FLOAT, GL_FALSE,0, 0);//BUFFER_OFFSET(0));
}
void mydisplay()
{
glClearColor(1.0f, 1.0f, 1.0f, 0.0f);//set the color for clearing the display
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); //the clear call will affect the color buffer
glPointSize(2); // set the point size
glDrawArrays(GL_POINTS,0,NoP);//Rendering verteces data
glutSwapBuffers();
}
int main(int argc, char** argv)
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE|GLUT_DEPTH);
glutInitWindowSize(600, 600);
glutInitWindowPosition(0,0);
glutCreateWindow("Sierpinski 3D");
glewInit();
init();
glEnable(GL_DEPTH_TEST);
glutDisplayFunc(mydisplay);
glutMainLoop();
}
Make sure you use FreeGLUT, Nate's GLUT is way, way old.
- Why would you use 'extern "C++"'?
- Strange Behavior Compiler Ignoring NULL Check Unless I Print Something in the if Statement
- Fast inverse square root using fixed point instead of floating point
- What is the const qualifier attached to in C: the memory area or the pointer?
- What is the scope of `fesetround()`?
- Is this declaration UB?
- GCC options for strictest C code?
- How to do an explicit fall-through in C
- How do compilers treat CONST qualifier when the pointer points to a memory location obtained with malloc()?
- C: cmocka headers - how to unittest?
- Why in C when I print a double with a one decimal it round it to the next number
- Android C to Java SWIG unable to compile: incompatible types: byte cannot be converted to SWIGTYPE_p_uint8_t
- GNU Make in Ubuntu giving fatal error: rpc/types.h: No such file or directory
- How can I exclude non-numeric keys? CS50 Caesar Pset2
- How change every struct in an array of pointers?
- Optimized 2x2 matrix multiplication: Slow assembly versus fast SIMD
- Simple frame by frame video decoder library
- GCC no longer implements <varargs.h>
- Contents of IO buffer unknown == unsafe?
- Avoiding strcpy overflow destination warning
- Sort program not working, not sure why
- Fast & accurate atan/arctan approximation algorithm
- What's the difference between strtok_r and strtok_s in C?
- How memory address for pointer to arrays is same as an element in 2D array?
- Which is the best way to suppress "unused variable" warning
- How to use ellipsis in c's case statement?
- Fast ceiling of an integer division in C / C++
- Is there an invalid pthread_t id?
- How to Implement Universal Setter/Getter Functions for Interrupt-Driven Variables in Embedded C?
- How does SIMD (avx) processing work? for example, if I want 10 32 bit floats how do i fit in a 256 bit avx vector?