Use GLSL shaders (still 1.20, though). Dump GL info.

git-svn-id: https://svn.code.sf.net/p/freeglut/code/trunk@777 7f0cb862-5218-0410-a997-914c9d46530a
This commit is contained in:
spanne 2009-02-15 17:53:48 +00:00
parent 2af3dd1eae
commit 3d7236a470

View File

@ -45,6 +45,7 @@
#include <GL/freeglut.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
/* report GL errors, if any, to stderr */
void checkError(const char *functionName)
@ -55,8 +56,28 @@ void checkError(const char *functionName)
}
}
/* extension types and entries, avoiding a dependency on additional libraries
like GLEW or the GL/glext.h header */
/* extension #defines, types and entries, avoiding a dependency on additional
libraries like GLEW or the GL/glext.h header */
#ifndef GL_VERTEX_SHADER
#define GL_VERTEX_SHADER 0x8B31
#endif
#ifndef GL_SHADING_LANGUAGE_VERSION
#define GL_SHADING_LANGUAGE_VERSION 0x8B8C
#endif
#ifndef GL_COMPILE_STATUS
#define GL_COMPILE_STATUS 0x8B81
#endif
#ifndef GL_LINK_STATUS
#define GL_LINK_STATUS 0x8B82
#endif
#ifndef GL_INFO_LOG_LENGTH
#define GL_INFO_LOG_LENGTH 0x8B84
#endif
typedef void (*PFNGLGENBUFFERSPROC) (GLsizei n, GLuint *buffers);
PFNGLGENBUFFERSPROC gl_GenBuffers;
@ -67,11 +88,58 @@ typedef void (*PFNGLBUFFERDATAPROC) (GLenum target, GLsizeiptr size,
const GLvoid *data, GLenum usage);
PFNGLBUFFERDATAPROC gl_BufferData;
typedef GLuint (*PFNGLCREATESHADERPROC) (GLenum type);
PFNGLCREATESHADERPROC gl_CreateShader;
typedef void (*PFNGLSHADERSOURCEPROC)
(GLuint shader, GLsizei count, const GLchar **string, const GLint *length);
PFNGLSHADERSOURCEPROC gl_ShaderSource;
typedef void (*PFNGLCOMPILESHADERPROC) (GLuint shader);
PFNGLCOMPILESHADERPROC gl_CompileShader;
typedef GLuint (*PFNGLCREATEPROGRAMPROC) (void);
PFNGLCREATEPROGRAMPROC gl_CreateProgram;
typedef void (*PFNGLATTACHSHADERPROC) (GLuint program, GLuint shader);
PFNGLATTACHSHADERPROC gl_AttachShader;
typedef void (*PFNGLLINKPROGRAMPROC) (GLuint program);
PFNGLLINKPROGRAMPROC gl_LinkProgram;
typedef void (*PFNGLUSEPROGRAMPROC) (GLuint program);
PFNGLUSEPROGRAMPROC gl_UseProgram;
typedef void (*PFNGLGETSHADERIVPROC) (GLuint shader, GLenum pname, GLint *params);
PFNGLGETSHADERIVPROC gl_GetShaderiv;
typedef void (*PFNGLGETSHADERINFOLOGPROC)
(GLuint shader, GLsizei bufSize, GLsizei *length, GLchar *infoLog);
PFNGLGETSHADERINFOLOGPROC gl_GetShaderInfoLog;
typedef void (*PFNGLGETPROGRAMIVPROC) (GLenum target, GLenum pname, GLint *params);
PFNGLGETPROGRAMIVPROC gl_GetProgramiv;
typedef void (*PFNGLGETPROGRAMINFOLOGPROC)
(GLuint program, GLsizei bufSize, GLsizei *length, GLchar *infoLog);
PFNGLGETPROGRAMINFOLOGPROC gl_GetProgramInfoLog;
void initExtensionEntries(void)
{
gl_GenBuffers = (PFNGLGENBUFFERSPROC) glutGetProcAddress ("glGenBuffers");
gl_BindBuffer = (PFNGLBINDBUFFERPROC) glutGetProcAddress ("glBindBuffer");
gl_BufferData = (PFNGLBUFFERDATAPROC) glutGetProcAddress ("glBufferData");
gl_CreateShader = (PFNGLCREATESHADERPROC) glutGetProcAddress ("glCreateShader");
gl_ShaderSource = (PFNGLSHADERSOURCEPROC) glutGetProcAddress ("glShaderSource");
gl_CompileShader = (PFNGLCOMPILESHADERPROC) glutGetProcAddress ("glCompileShader");
gl_CreateProgram = (PFNGLCREATEPROGRAMPROC) glutGetProcAddress ("glCreateProgram");
gl_AttachShader = (PFNGLATTACHSHADERPROC) glutGetProcAddress ("glAttachShader");
gl_LinkProgram = (PFNGLLINKPROGRAMPROC) glutGetProcAddress ("glLinkProgram");
gl_UseProgram = (PFNGLUSEPROGRAMPROC) glutGetProcAddress ("glUseProgram");
gl_GetShaderiv = (PFNGLGETSHADERIVPROC) glutGetProcAddress ("glGetShaderiv");
gl_GetShaderInfoLog = (PFNGLGETSHADERINFOLOGPROC) glutGetProcAddress ("glGetShaderInfoLog");
gl_GetProgramiv = (PFNGLGETPROGRAMIVPROC) glutGetProcAddress ("glGetProgramiv");
gl_GetProgramInfoLog = (PFNGLGETPROGRAMINFOLOGPROC) glutGetProcAddress ("glGetProgramInfoLog");
}
/* vertex array data for a colored 2D triangle, consisting of RGB color values
@ -108,6 +176,91 @@ void initBuffer(void)
checkError ("initBuffer");
}
const GLchar *vertexShaderSource[] = {
"#version 120\n",
"void main(void)\n",
"{\n",
" gl_FrontColor = gl_Color;\n",
" gl_Position = ftransform();\n",
"}\n"
};
const GLchar *fragmentShaderSource[] = {
"#version 120\n",
"void main(void)\n",
"{\n",
" gl_FragColor = gl_Color;\n",
"}\n"
};
void compileAndCheck(GLuint shader)
{
GLint status;
gl_CompileShader (shader);
gl_GetShaderiv (shader, GL_COMPILE_STATUS, &status);
if (status == GL_FALSE) {
GLint infoLogLength;
GLchar *infoLog;
gl_GetShaderiv (shader, GL_INFO_LOG_LENGTH, &infoLogLength);
infoLog = (GLchar*) malloc (infoLogLength);
gl_GetShaderInfoLog (shader, infoLogLength, NULL, infoLog);
fprintf (stderr, "compile log: %s\n", infoLog);
free (infoLog);
}
}
GLuint compileShaderSource(GLenum type, GLsizei count, const GLchar **string)
{
GLuint shader = gl_CreateShader (type);
gl_ShaderSource (shader, count, string, NULL);
compileAndCheck (shader);
return shader;
}
void linkAndCheck(GLuint program)
{
GLint status;
gl_LinkProgram (program);
gl_GetProgramiv (program, GL_LINK_STATUS, &status);
if (status == GL_FALSE) {
GLint infoLogLength;
GLchar *infoLog;
gl_GetProgramiv (program, GL_INFO_LOG_LENGTH, &infoLogLength);
infoLog = (GLchar*) malloc (infoLogLength);
gl_GetProgramInfoLog (program, infoLogLength, NULL, infoLog);
fprintf (stderr, "link log: %s\n", infoLog);
free (infoLog);
}
}
GLuint createProgram(GLuint vertexShader, GLuint fragmentShader)
{
GLuint program = gl_CreateProgram ();
if (vertexShader != 0) {
gl_AttachShader (program, vertexShader);
}
if (fragmentShader != 0) {
gl_AttachShader (program, fragmentShader);
}
linkAndCheck (program);
return program;
}
void initShader(void)
{
const GLsizei vertexShaderLines = sizeof(vertexShaderSource) / sizeof(GLchar*);
GLuint vertexShader =
compileShaderSource (GL_VERTEX_SHADER, vertexShaderLines, vertexShaderSource);
const GLsizei fragmentShaderLines = sizeof(fragmentShaderSource) / sizeof(GLchar*);
GLuint fragmentShader =
compileShaderSource (GL_FRAGMENT_SHADER, fragmentShaderLines, fragmentShaderSource);
GLuint program = createProgram (vertexShader, fragmentShader);
gl_UseProgram (program);
checkError ("initShader");
}
void initRendering(void)
{
glClearColor (0.0, 0.0, 0.0, 0.0);
@ -117,9 +270,19 @@ void initRendering(void)
void init(void)
{
initExtensionEntries();
initBuffer();
initRendering();
initExtensionEntries ();
initBuffer ();
initShader ();
initRendering ();
}
void dumpInfo(void)
{
printf ("Vendor: %s\n", glGetString (GL_VENDOR));
printf ("Renderer: %s\n", glGetString (GL_RENDERER));
printf ("Version: %s\n", glGetString (GL_VERSION));
printf ("GLSL: %s\n", glGetString (GL_SHADING_LANGUAGE_VERSION));
checkError ("dumpInfo");
}
const GLvoid *bufferObjectPtr (GLsizei index)
@ -210,6 +373,7 @@ int main(int argc, char** argv)
glutInitWindowSize (500, 500);
glutInitWindowPosition (100, 100);
glutCreateWindow (argv[0]);
dumpInfo ();
init ();
glutDisplayFunc(display);
glutReshapeFunc(reshape);