mirror of
https://gitlab.freedesktop.org/mesa/mesa.git
synced 2025-12-28 10:20:09 +01:00
Demonstrate GLSL fragment and vertex shaders.
This commit is contained in:
Michal Krol
parent
d5aca8bf0c
commit
3699751b0b
2 changed files with 286 additions and 0 deletions
|
|
@ -15,6 +15,7 @@ LIB_DEP = $(LIB_DIR)/$(GL_LIB_NAME) $(LIB_DIR)/$(GLU_LIB_NAME) $(LIB_DIR)/$(GLUT
|
|||
|
||||
PROGS = \
|
||||
arbfplight \
|
||||
arbfslight \
|
||||
arbocclude \
|
||||
bounce \
|
||||
clearspd \
|
||||
|
|
|
|||
285
progs/demos/arbfslight.c
Normal file
285
progs/demos/arbfslight.c
Normal file
|
|
@ -0,0 +1,285 @@
|
|||
/*
|
||||
* Use GL_ARB_fragment_shader and GL_ARB_vertex_shader to implement
|
||||
* simple per-pixel lighting.
|
||||
*
|
||||
* Michal Krol
|
||||
* 14 February 2006
|
||||
*
|
||||
* Based on the original demo by:
|
||||
* Brian Paul
|
||||
* 17 April 2003
|
||||
*/
|
||||
|
||||
#include <stdio.h>
|
||||
#include <stdlib.h>
|
||||
#include <GL/glut.h>
|
||||
|
||||
static GLfloat diffuse[4] = { 0.5f, 0.5f, 1.0f, 1.0f };
|
||||
static GLfloat specular[4] = { 0.8f, 0.8f, 0.8f, 1.0f };
|
||||
static GLfloat lightPos[4] = { 0.0f, 10.0f, 20.0f, 1.0f };
|
||||
static GLfloat delta = 1.0f;
|
||||
|
||||
static GLhandleARB fragShader;
|
||||
static GLhandleARB vertShader;
|
||||
static GLhandleARB program;
|
||||
|
||||
static GLboolean anim = GL_TRUE;
|
||||
static GLboolean wire = GL_FALSE;
|
||||
static GLboolean pixelLight = GL_TRUE;
|
||||
|
||||
static GLint t0 = 0;
|
||||
static GLint frames = 0;
|
||||
|
||||
static GLfloat xRot = 0.0f, yRot = 0.0f;
|
||||
|
||||
static PFNGLCREATESHADEROBJECTARBPROC glCreateShaderObjectARB = NULL;
|
||||
static PFNGLSHADERSOURCEARBPROC glShaderSourceARB = NULL;
|
||||
static PFNGLCOMPILESHADERARBPROC glCompileShaderARB = NULL;
|
||||
static PFNGLCREATEPROGRAMOBJECTARBPROC glCreateProgramObjectARB = NULL;
|
||||
static PFNGLATTACHOBJECTARBPROC glAttachObjectARB = NULL;
|
||||
static PFNGLLINKPROGRAMARBPROC glLinkProgramARB = NULL;
|
||||
static PFNGLUSEPROGRAMOBJECTARBPROC glUseProgramObjectARB = NULL;
|
||||
|
||||
static void Redisplay (void)
|
||||
{
|
||||
glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
|
||||
|
||||
if (pixelLight)
|
||||
{
|
||||
glUseProgramObjectARB (program);
|
||||
/* XXX source from uniform lightPos */
|
||||
glTexCoord4fv (lightPos);
|
||||
glDisable(GL_LIGHTING);
|
||||
}
|
||||
else
|
||||
{
|
||||
glUseProgramObjectARB (0);
|
||||
glLightfv (GL_LIGHT0, GL_POSITION, lightPos);
|
||||
glEnable(GL_LIGHTING);
|
||||
}
|
||||
|
||||
glPushMatrix ();
|
||||
glRotatef (xRot, 1.0f, 0.0f, 0.0f);
|
||||
glRotatef (yRot, 0.0f, 1.0f, 0.0f);
|
||||
glutSolidSphere (2.0, 10, 5);
|
||||
glPopMatrix ();
|
||||
|
||||
glutSwapBuffers();
|
||||
frames++;
|
||||
|
||||
if (anim)
|
||||
{
|
||||
GLint t = glutGet (GLUT_ELAPSED_TIME);
|
||||
if (t - t0 >= 5000)
|
||||
{
|
||||
GLfloat seconds = (GLfloat) (t - t0) / 1000.0f;
|
||||
GLfloat fps = frames / seconds;
|
||||
printf ("%d frames in %6.3f seconds = %6.3f FPS\n", frames, seconds, fps);
|
||||
t0 = t;
|
||||
frames = 0;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
static void Idle (void)
|
||||
{
|
||||
lightPos[0] += delta;
|
||||
if (lightPos[0] > 25.0f || lightPos[0] < -25.0f)
|
||||
delta = -delta;
|
||||
glutPostRedisplay ();
|
||||
}
|
||||
|
||||
static void Reshape (int width, int height)
|
||||
{
|
||||
glViewport (0, 0, width, height);
|
||||
glMatrixMode (GL_PROJECTION);
|
||||
glLoadIdentity ();
|
||||
glFrustum (-1.0, 1.0, -1.0, 1.0, 5.0, 25.0);
|
||||
glMatrixMode (GL_MODELVIEW);
|
||||
glLoadIdentity ();
|
||||
glTranslatef (0.0f, 0.0f, -15.0f);
|
||||
}
|
||||
|
||||
static void Key (unsigned char key, int x, int y)
|
||||
{
|
||||
(void) x;
|
||||
(void) y;
|
||||
|
||||
switch (key)
|
||||
{
|
||||
case ' ':
|
||||
case 'a':
|
||||
anim = !anim;
|
||||
if (anim)
|
||||
glutIdleFunc (Idle);
|
||||
else
|
||||
glutIdleFunc (NULL);
|
||||
break;
|
||||
case 'x':
|
||||
lightPos[0] -= 1.0f;
|
||||
break;
|
||||
case 'X':
|
||||
lightPos[0] += 1.0f;
|
||||
break;
|
||||
case 'w':
|
||||
wire = !wire;
|
||||
if (wire)
|
||||
glPolygonMode (GL_FRONT_AND_BACK, GL_LINE);
|
||||
else
|
||||
glPolygonMode (GL_FRONT_AND_BACK, GL_FILL);
|
||||
break;
|
||||
case 'p':
|
||||
pixelLight = !pixelLight;
|
||||
if (pixelLight)
|
||||
printf ("Per-pixel lighting\n");
|
||||
else
|
||||
printf ("Conventional lighting\n");
|
||||
break;
|
||||
case 27:
|
||||
exit(0);
|
||||
break;
|
||||
}
|
||||
glutPostRedisplay ();
|
||||
}
|
||||
|
||||
static void SpecialKey (int key, int x, int y)
|
||||
{
|
||||
const GLfloat step = 3.0f;
|
||||
|
||||
(void) x;
|
||||
(void) y;
|
||||
|
||||
switch (key)
|
||||
{
|
||||
case GLUT_KEY_UP:
|
||||
xRot -= step;
|
||||
break;
|
||||
case GLUT_KEY_DOWN:
|
||||
xRot += step;
|
||||
break;
|
||||
case GLUT_KEY_LEFT:
|
||||
yRot -= step;
|
||||
break;
|
||||
case GLUT_KEY_RIGHT:
|
||||
yRot += step;
|
||||
break;
|
||||
}
|
||||
glutPostRedisplay ();
|
||||
}
|
||||
|
||||
static void Init (void)
|
||||
{
|
||||
static const char *fragShaderText =
|
||||
"void main () {\n"
|
||||
|
||||
/* XXX source from uniform lightPos */
|
||||
" vec4 lightPos;\n"
|
||||
" lightPos = gl_TexCoord[1];\n"
|
||||
|
||||
/* XXX source from uniform diffuse */
|
||||
" vec4 diffuse;\n"
|
||||
" diffuse.xy = vec2 (0.5);\n"
|
||||
" diffuse.zw = vec2 (1.0);\n"
|
||||
|
||||
/* XXX source from uniform specular */
|
||||
" vec4 specular;\n"
|
||||
" specular.xyz = vec3 (0.8);\n"
|
||||
" specular.w = 1.0;\n"
|
||||
|
||||
" // Compute normalized light direction\n"
|
||||
" vec4 lightDir;\n"
|
||||
" lightDir = lightPos / length (lightPos);\n"
|
||||
" // Compute normalized normal\n"
|
||||
" vec4 normal;\n"
|
||||
" normal = gl_TexCoord[0] / length (gl_TexCoord[0]);\n"
|
||||
" // Compute dot product of light direction and normal vector\n"
|
||||
" float dotProd;\n"
|
||||
" dotProd = clamp (dot (lightDir.xyz, normal.xyz), 0.0, 1.0);\n"
|
||||
" // Compute diffuse and specular contributions\n"
|
||||
" gl_FragColor = diffuse * dotProd + specular * pow (dotProd, 20.0);\n"
|
||||
"}\n"
|
||||
;
|
||||
static const char *vertShaderText =
|
||||
"void main () {\n"
|
||||
" gl_Position = gl_ModelViewProjectionMatrix * gl_Vertex;\n"
|
||||
" gl_TexCoord[0].xyz = gl_NormalMatrix * gl_Normal;\n"
|
||||
" gl_TexCoord[0].w = 1.0;\n"
|
||||
|
||||
/* XXX source from uniform lightPos */
|
||||
" gl_TexCoord[1] = gl_MultiTexCoord0;\n"
|
||||
"}\n"
|
||||
;
|
||||
|
||||
if (!glutExtensionSupported ("GL_ARB_fragment_shader"))
|
||||
{
|
||||
printf ("Sorry, this demo requires GL_ARB_fragment_shader\n");
|
||||
exit(1);
|
||||
}
|
||||
if (!glutExtensionSupported ("GL_ARB_shader_objects"))
|
||||
{
|
||||
printf ("Sorry, this demo requires GL_ARB_shader_objects\n");
|
||||
exit(1);
|
||||
}
|
||||
if (!glutExtensionSupported ("GL_ARB_shading_language_100"))
|
||||
{
|
||||
printf ("Sorry, this demo requires GL_ARB_shading_language_100\n");
|
||||
exit(1);
|
||||
}
|
||||
if (!glutExtensionSupported ("GL_ARB_vertex_shader"))
|
||||
{
|
||||
printf ("Sorry, this demo requires GL_ARB_vertex_shader\n");
|
||||
exit(1);
|
||||
}
|
||||
|
||||
glCreateShaderObjectARB = (PFNGLCREATESHADEROBJECTARBPROC) glutGetProcAddress ("glCreateShaderObjectARB");
|
||||
glShaderSourceARB = (PFNGLSHADERSOURCEARBPROC) glutGetProcAddress ("glShaderSourceARB");
|
||||
glCompileShaderARB = (PFNGLCOMPILESHADERARBPROC) glutGetProcAddress ("glCompileShaderARB");
|
||||
glCreateProgramObjectARB = (PFNGLCREATEPROGRAMOBJECTARBPROC) glutGetProcAddress ("glCreateProgramObjectARB");
|
||||
glAttachObjectARB = (PFNGLATTACHOBJECTARBPROC) glutGetProcAddress ("glAttachObjectARB");
|
||||
glLinkProgramARB = (PFNGLLINKPROGRAMARBPROC) glutGetProcAddress ("glLinkProgramARB");
|
||||
glUseProgramObjectARB = (PFNGLUSEPROGRAMOBJECTARBPROC) glutGetProcAddress ("glUseProgramObjectARB");
|
||||
|
||||
fragShader = glCreateShaderObjectARB (GL_FRAGMENT_SHADER_ARB);
|
||||
glShaderSourceARB (fragShader, 1, &fragShaderText, NULL);
|
||||
glCompileShaderARB (fragShader);
|
||||
|
||||
vertShader = glCreateShaderObjectARB (GL_VERTEX_SHADER_ARB);
|
||||
glShaderSourceARB (vertShader, 1, &vertShaderText, NULL);
|
||||
glCompileShaderARB (vertShader);
|
||||
|
||||
program = glCreateProgramObjectARB ();
|
||||
glAttachObjectARB (program, fragShader);
|
||||
glAttachObjectARB (program, vertShader);
|
||||
glLinkProgramARB (program);
|
||||
glUseProgramObjectARB (program);
|
||||
|
||||
glClearColor (0.3f, 0.3f, 0.3f, 0.0f);
|
||||
glEnable (GL_DEPTH_TEST);
|
||||
glEnable (GL_LIGHT0);
|
||||
glEnable (GL_LIGHTING);
|
||||
glMaterialfv (GL_FRONT_AND_BACK, GL_DIFFUSE, diffuse);
|
||||
glMaterialfv (GL_FRONT_AND_BACK, GL_SPECULAR, specular);
|
||||
glMaterialf (GL_FRONT_AND_BACK, GL_SHININESS, 20.0f);
|
||||
|
||||
printf ("GL_RENDERER = %s\n", (const char *) glGetString (GL_RENDERER));
|
||||
printf ("Press p to toggle between per-pixel and per-vertex lighting\n");
|
||||
}
|
||||
|
||||
int main (int argc, char *argv[])
|
||||
{
|
||||
glutInit (&argc, argv);
|
||||
glutInitWindowPosition ( 0, 0);
|
||||
glutInitWindowSize (200, 200);
|
||||
glutInitDisplayMode (GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH);
|
||||
glutCreateWindow (argv[0]);
|
||||
glutReshapeFunc (Reshape);
|
||||
glutKeyboardFunc (Key);
|
||||
glutSpecialFunc (SpecialKey);
|
||||
glutDisplayFunc (Redisplay);
|
||||
if (anim)
|
||||
glutIdleFunc (Idle);
|
||||
Init ();
|
||||
glutMainLoop ();
|
||||
return 0;
|
||||
}
|
||||
|
||||
Loading…
Add table
Reference in a new issue