+++ /dev/null
-/*
- * Warp a triangle mesh with a vertex program.
- */
-
-#include <assert.h>
-#include <string.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <math.h>
-#include <GL/glew.h>
-#include <GL/glut.h>
-
-static float Xrot = -60.0, Yrot = 0.0, Zrot = 0.0;
-static GLboolean Anim = GL_TRUE;
-static GLfloat Phi = 0.0;
-
-
-static void Idle( void )
-{
- Phi += 0.01;
- glutPostRedisplay();
-}
-
-
-static void DrawMesh( int rows, int cols )
-{
- static const GLfloat colorA[3] = { 0, 1, 0 };
- static const GLfloat colorB[3] = { 0, 0, 1 };
- const float dx = 2.0 / (cols - 1);
- const float dy = 2.0 / (rows - 1);
- float x, y;
- int i, j;
-
-#if 1
-#define COLOR3FV(c) glVertexAttrib3fvARB(3, c)
-#define VERTEX2F(x, y) glVertexAttrib2fARB(0, x, y)
-#else
-#define COLOR3FV(c) glColor3fv(c)
-#define VERTEX2F(x, y) glVertex2f(x, y)
-#endif
-
- y = -1.0;
- for (i = 0; i < rows - 1; i++) {
- glBegin(GL_QUAD_STRIP);
- x = -1.0;
- for (j = 0; j < cols; j++) {
- if ((i + j) & 1)
- COLOR3FV(colorA);
- else
- COLOR3FV(colorB);
- VERTEX2F(x, y);
- VERTEX2F(x, y + dy);
- x += dx;
- }
- glEnd();
- y += dy;
- }
-}
-
-
-static void Display( void )
-{
- glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
-
- glPushMatrix();
- glRotatef(Xrot, 1, 0, 0);
- glRotatef(Yrot, 0, 1, 0);
- glRotatef(Zrot, 0, 0, 1);
-
- /* Position the gravity source */
- {
- GLfloat x, y, z, r = 0.5;
- x = r * cos(Phi);
- y = r * sin(Phi);
- z = 1.0;
- glProgramLocalParameter4fARB(GL_VERTEX_PROGRAM_ARB, 30, x, y, z, 1);
- glDisable(GL_VERTEX_PROGRAM_ARB);
- glBegin(GL_POINTS);
- glColor3f(1,1,1);
- glVertex3f(x, y, z);
- glEnd();
- }
-
- glEnable(GL_VERTEX_PROGRAM_ARB);
- DrawMesh(8, 8);
- glPopMatrix();
-
- glutSwapBuffers();
-}
-
-
-static void Reshape( int width, int height )
-{
- float ar = (float) width / (float) height;
- glViewport( 0, 0, width, height );
- glMatrixMode( GL_PROJECTION );
- glLoadIdentity();
- glFrustum( -1.0 * ar, 1.0 * ar, -1.0, 1.0, 5.0, 25.0 );
- glMatrixMode( GL_MODELVIEW );
- glLoadIdentity();
- glTranslatef( 0.0, 0.0, -12.0 );
- glScalef(2, 2, 2);
-}
-
-
-static void Key( unsigned char key, int x, int y )
-{
- (void) x;
- (void) y;
- switch (key) {
- case 'a':
- Anim = !Anim;
- if (Anim)
- glutIdleFunc(Idle);
- else
- glutIdleFunc(NULL);
- break;
- case 'p':
- Phi += 0.2;
- break;
- case 'z':
- Zrot -= 5.0;
- break;
- case 'Z':
- Zrot += 5.0;
- 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 )
-{
- GLuint prognum;
- GLint errno;
-
- /*
- * c[0..3] = modelview matrix
- * c[4..7] = inverse modelview matrix
- * c[30] = gravity source location
- * c[31] = gravity source strength
- * c[32] = light pos
- * c[35] = diffuse color
- */
- static const char prog[] =
- "!!ARBvp1.0\n"
- "TEMP R1, R2, R3; "
-
- "# Compute distance from vertex to gravity source\n"
- "ADD R1, program.local[30], -vertex.position; # vector from vertex to gravity\n"
- "DP3 R2, R1, R1; # dot product\n"
- "RSQ R2, R2.x; # square root = distance\n"
- "MUL R2, R2, program.local[31].xxxx; # scale by the gravity factor\n"
-
- "# Displace vertex by gravity factor along R1 vector\n"
- "MAD R3, R1, R2, vertex.position;\n"
-
- "# Continue with typical modelview/projection\n"
- "DP4 result.position.x, state.matrix.mvp.row[0], R3 ; # object x MVP -> clip\n"
- "DP4 result.position.y, state.matrix.mvp.row[1], R3 ;\n"
- "DP4 result.position.z, state.matrix.mvp.row[2], R3 ;\n"
- "DP4 result.position.w, state.matrix.mvp.row[3], R3 ;\n"
-
- "MOV result.color, vertex.attrib[3];\n # copy input color to output color\n"
-
- "END";
-
- if (!glutExtensionSupported("GL_ARB_vertex_program")) {
- printf("Sorry, this program requires GL_ARB_vertex_program\n");
- exit(1);
- }
-
- glGenProgramsARB(1, &prognum);
- glBindProgramARB(GL_VERTEX_PROGRAM_ARB, prognum);
- glProgramStringARB(GL_VERTEX_PROGRAM_ARB, GL_PROGRAM_FORMAT_ASCII_ARB,
- strlen(prog), (const GLubyte *)prog);
- errno = glGetError();
- printf("glGetError = %d\n", errno);
-
- if (errno != GL_NO_ERROR)
- {
- GLint errorpos;
-
- glGetIntegerv(GL_PROGRAM_ERROR_POSITION_ARB, &errorpos);
- printf("errorpos: %d\n", errorpos);
- printf("%s\n", glGetString(GL_PROGRAM_ERROR_STRING_ARB));
- }
-
- /* Light position */
- glProgramLocalParameter4fARB(GL_VERTEX_PROGRAM_ARB, 32, 2, 2, 4, 1);
- /* Diffuse material color */
- glProgramLocalParameter4fARB(GL_VERTEX_PROGRAM_ARB, 35, 0.25, 0, 0.25, 1);
-
- /* Gravity strength */
- glProgramLocalParameter4fARB(GL_VERTEX_PROGRAM_ARB, 31, .5, 0, 0, 0);
-
- glEnable(GL_DEPTH_TEST);
- glClearColor(0.3, 0.3, 0.3, 1);
- glShadeModel(GL_FLAT);
- glPointSize(3);
-}
-
-
-int main( int argc, char *argv[] )
-{
- glutInit( &argc, argv );
- glutInitWindowPosition( 0, 0 );
- glutInitWindowSize( 250, 250 );
- glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH );
- glutCreateWindow(argv[0]);
- glewInit();
- glutReshapeFunc( Reshape );
- glutKeyboardFunc( Key );
- glutSpecialFunc( SpecialKey );
- glutDisplayFunc( Display );
- if (Anim)
- glutIdleFunc(Idle);
- Init();
- glutMainLoop();
- return 0;
-}
projects / mesa.git / blobdiff