--- /dev/null
+/*
+ * Use GL_NV_fragment_program to implement per-pixel lighting.
+ *
+ * Brian Paul
+ * 7 April 2003
+ */
+
+#include <assert.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#define GL_GLEXT_PROTOTYPES
+#include <GL/glut.h>
+
+
+static GLfloat Diffuse[4] = { 0.5, 0.5, 1.0, 1.0 };
+static GLfloat Specular[4] = { 0.8, 0.8, 0.8, 1.0 };
+static GLfloat LightPos[4] = { 0.0, 10.0, 20.0, 1.0 };
+static GLfloat Delta = 1.0;
+
+static GLuint FragProg;
+static GLuint VertProg;
+static GLboolean Anim = GL_TRUE;
+static GLboolean Wire = GL_FALSE;
+static GLboolean PixelLight = GL_TRUE;
+
+static GLfloat Xrot = 0, Yrot = 0;
+
+
+#define NAMED_PARAMETER4FV(prog, name, v) \
+ glProgramNamedParameter4fvNV(prog, strlen(name), (const GLubyte *) name, v)
+
+
+static void Display( void )
+{
+ glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
+
+ if (PixelLight) {
+ NAMED_PARAMETER4FV(FragProg, "LightPos", LightPos);
+ glEnable(GL_FRAGMENT_PROGRAM_NV);
+ glEnable(GL_VERTEX_PROGRAM_NV);
+ glDisable(GL_LIGHTING);
+ }
+ else {
+ glLightfv(GL_LIGHT0, GL_POSITION, LightPos);
+ glDisable(GL_FRAGMENT_PROGRAM_NV);
+ glDisable(GL_VERTEX_PROGRAM_NV);
+ glEnable(GL_LIGHTING);
+ }
+
+ glPushMatrix();
+ glRotatef(Xrot, 1, 0, 0);
+ glRotatef(Yrot, 0, 1, 0);
+
+ glTexCoord2f(0, 0);
+#if 1
+ glutSolidSphere(2.0, 10, 5);
+#else
+ {
+ GLUquadricObj *q = gluNewQuadric();
+ gluQuadricNormals(q, GL_SMOOTH);
+ gluQuadricTexture(q, GL_TRUE);
+ glRotatef(90, 1, 0, 0);
+ glTranslatef(0, 0, -1);
+ gluCylinder(q, 1.0, 1.0, 2.0, 24, 1);
+ gluDeleteQuadric(q);
+ }
+#endif
+
+ glPopMatrix();
+
+ glutSwapBuffers();
+}
+
+
+static void Idle(void)
+{
+ LightPos[0] += Delta;
+ if (LightPos[0] > 25.0)
+ Delta = -1.0;
+ else if (LightPos[0] <- 25.0)
+ Delta = 1.0;
+ 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 );
+ /*glOrtho( -2.0, 2.0, -2.0, 2.0, 5.0, 25.0 );*/
+ glMatrixMode( GL_MODELVIEW );
+ glLoadIdentity();
+ glTranslatef( 0.0, 0.0, -15.0 );
+}
+
+
+static void Key( unsigned char key, int x, int y )
+{
+ (void) x;
+ (void) y;
+ switch (key) {
+ case ' ':
+ Anim = !Anim;
+ if (Anim)
+ glutIdleFunc(Idle);
+ else
+ glutIdleFunc(NULL);
+ break;
+ case 'x':
+ LightPos[0] -= 1.0;
+ break;
+ case 'X':
+ LightPos[0] += 1.0;
+ 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 = 3.0;
+ (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 *fragProgramText =
+ "!!FP1.0\n"
+ "DECLARE Diffuse; \n"
+ "DECLARE Specular; \n"
+ "DECLARE LightPos; \n"
+
+ "# Compute normalized LightPos, put it in R0\n"
+ "DP3 R0.x, LightPos, LightPos;\n"
+ "RSQ R0.y, R0.x;\n"
+ "MUL R0, LightPos, R0.y;\n"
+
+ "# Compute normalized normal, put it in R1\n"
+ "DP3 R1, f[TEX0], f[TEX0]; \n"
+ "RSQ R1.y, R1.x;\n"
+ "MUL R1, f[TEX0], R1.y;\n"
+
+ "# Compute dot product of light direction and normal vector\n"
+ "DP3 R2, R0, R1;"
+
+ "MUL R3, Diffuse, R2; # diffuse attenuation\n"
+
+ "POW R4, R2.x, {20.0}.x; # specular exponent\n"
+
+ "MUL R5, Specular, R4; # specular attenuation\n"
+
+ "ADD o[COLR], R3, R5; # add diffuse and specular colors\n"
+ "END \n"
+ ;
+
+ static const char *vertProgramText =
+ "!!VP1.0\n"
+ "# typical modelview/projection transform\n"
+ "DP4 o[HPOS].x, c[0], v[OPOS] ;\n"
+ "DP4 o[HPOS].y, c[1], v[OPOS] ;\n"
+ "DP4 o[HPOS].z, c[2], v[OPOS] ;\n"
+ "DP4 o[HPOS].w, c[3], v[OPOS] ;\n"
+ "# transform normal by inv transpose of modelview, put in tex0\n"
+ "DP4 o[TEX0].x, c[4], v[NRML] ;\n"
+ "DP4 o[TEX0].y, c[5], v[NRML] ;\n"
+ "DP4 o[TEX0].z, c[6], v[NRML] ;\n"
+ "DP4 o[TEX0].w, c[7], v[NRML] ;\n"
+ "END\n";
+ ;
+
+ if (!glutExtensionSupported("GL_NV_vertex_program")) {
+ printf("Sorry, this demo requires GL_NV_vertex_program\n");
+ exit(1);
+ }
+ if (!glutExtensionSupported("GL_NV_fragment_program")) {
+ printf("Sorry, this demo requires GL_NV_fragment_program\n");
+ exit(1);
+ }
+
+ glGenProgramsNV(1, &FragProg);
+ glGenProgramsNV(1, &VertProg);
+
+ /*
+ * Fragment program
+ */
+ glLoadProgramNV(GL_FRAGMENT_PROGRAM_NV, FragProg,
+ strlen(fragProgramText),
+ (const GLubyte *) fragProgramText);
+ assert(glIsProgramNV(FragProg));
+ glBindProgramNV(GL_FRAGMENT_PROGRAM_NV, FragProg);
+
+ NAMED_PARAMETER4FV(FragProg, "Diffuse", Diffuse);
+ NAMED_PARAMETER4FV(FragProg, "Specular", Specular);
+
+ /*
+ * Vertex program
+ */
+ glLoadProgramNV(GL_VERTEX_PROGRAM_NV, VertProg,
+ strlen(vertProgramText),
+ (const GLubyte *) vertProgramText);
+ assert(glIsProgramNV(VertProg));
+ glBindProgramNV(GL_VERTEX_PROGRAM_NV, VertProg);
+ glTrackMatrixNV(GL_VERTEX_PROGRAM_NV, 0, GL_MODELVIEW_PROJECTION_NV, GL_IDENTITY_NV);
+ glTrackMatrixNV(GL_VERTEX_PROGRAM_NV, 4, GL_MODELVIEW, GL_INVERSE_TRANSPOSE_NV);
+
+ /*
+ * Misc init
+ */
+ glClearColor(0.3, 0.3, 0.3, 0.0);
+ glEnable(GL_ALPHA_TEST); /* temporary hack */
+ 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, 20.0);
+
+ printf("GL_RENDERER = %s\n", (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( Display );
+ if (Anim)
+ glutIdleFunc(Idle);
+ Init();
+ glutMainLoop();
+ return 0;
+}
projects / mesa.git / commitdiff