+++ /dev/null
-/**
- * Test two-sided lighting with shaders.
- * Both GL_VERTEX_PROGRAM_TWO_SIDE and gl_FrontFacing can be tested
- * (see keys below).
- *
- * Brian Paul
- * 18 Dec 2007
- */
-
-#include <assert.h>
-#include <string.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <math.h>
-#include <GL/glew.h>
-#include <GL/glut.h>
-#include "shaderutil.h"
-
-#ifndef M_PI
-#define M_PI 3.1415926535
-#endif
-
-static GLint WinWidth = 300, WinHeight = 300;
-static char *FragProgFile = NULL;
-static char *VertProgFile = NULL;
-static GLuint fragShader;
-static GLuint vertShader;
-static GLuint program;
-static GLint win = 0;
-static GLboolean anim;
-static GLboolean DetermineFacingInFragProg;
-static GLfloat Xrot;
-static GLint u_fragface;
-static GLenum FrontWinding;
-static int prevTime = 0;
-
-
-static const GLfloat Red[4] = {1, 0, 0, 1};
-static const GLfloat Green[4] = {0, 1, 0, 0};
-
-
-static void
-SetDefaults(void)
-{
- DetermineFacingInFragProg = GL_TRUE;
- FrontWinding = GL_CCW;
- Xrot = 30;
- anim = 0;
- glutIdleFunc(NULL);
-}
-
-
-static void
-Redisplay(void)
-{
- const int sections = 20;
- int i;
- float radius = 2;
-
- glFrontFace(FrontWinding);
-
- if (DetermineFacingInFragProg) {
- glUniform1i(u_fragface, 1);
- glDisable(GL_VERTEX_PROGRAM_TWO_SIDE);
- }
- else {
- glUniform1i(u_fragface, 0);
- glEnable(GL_VERTEX_PROGRAM_TWO_SIDE);
- }
-
- glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
-
- glPushMatrix();
- glRotatef(Xrot, 1, 0, 0);
-
- /* Draw a tristrip ring */
- glBegin(GL_TRIANGLE_STRIP);
- glColor4fv(Red);
- glSecondaryColor3fv(Green);
- for (i = 0; i <= sections; i++) {
- float a = (float) i / (sections) * M_PI * 2.0;
- float x = radius * cos(a);
- float y = radius * sin(a);
- glVertex3f(x, -1, y);
- glVertex3f(x, +1, y);
- }
- glEnd();
-
- glPopMatrix();
-
- glutSwapBuffers();
-}
-
-
-static void
-Idle(void)
-{
- int curTime = glutGet(GLUT_ELAPSED_TIME);
- int dt = curTime - prevTime;
-
- if (prevTime == 0) {
- prevTime = curTime;
- return;
- }
- prevTime = curTime;
-
- Xrot += dt * 0.1;
- glutPostRedisplay();
-}
-
-
-static void
-Reshape(int width, int height)
-{
- float ar = (float) width / height;
- glViewport(0, 0, width, height);
- glMatrixMode(GL_PROJECTION);
- glLoadIdentity();
- glFrustum(-ar, ar, -1, 1, 3, 25);
- glMatrixMode(GL_MODELVIEW);
- glLoadIdentity();
- glTranslatef(0, 0, -10);
-}
-
-
-static void
-CleanUp(void)
-{
- glDeleteShader(fragShader);
- glDeleteShader(vertShader);
- glDeleteProgram(program);
- glutDestroyWindow(win);
-}
-
-
-static void
-Key(unsigned char key, int x, int y)
-{
- (void) x;
- (void) y;
-
- switch(key) {
- case ' ':
- case 'a':
- anim = !anim;
- if (anim) {
- prevTime = glutGet(GLUT_ELAPSED_TIME);
- glutIdleFunc(Idle);
- }
- else
- glutIdleFunc(NULL);
- break;
- case 'f':
- printf("Using frag shader gl_FrontFacing\n");
- DetermineFacingInFragProg = GL_TRUE;
- break;
- case 'v':
- printf("Using vert shader Two-sided lighting\n");
- DetermineFacingInFragProg = GL_FALSE;
- break;
- case 'r':
- /* reset */
- SetDefaults();
- break;
- case 's':
- Xrot += 5;
- break;
- case 'S':
- Xrot -= 5;
- break;
- case 'w':
- if (FrontWinding == GL_CCW) {
- FrontWinding = GL_CW;
- printf("FrontFace = GL_CW\n");
- }
- else {
- FrontWinding = GL_CCW;
- printf("FrontFace = GL_CCW\n");
- }
- break;
- case 27:
- CleanUp();
- exit(0);
- break;
- }
- glutPostRedisplay();
-}
-
-
-static void
-Init(void)
-{
- static const char *fragShaderText =
- "uniform bool fragface; \n"
- "void main() { \n"
-#if 1
- " if (!fragface || gl_FrontFacing) { \n"
- " gl_FragColor = gl_Color; \n"
- " } \n"
- " else { \n"
- " // note: dim green to help debug \n"
- " gl_FragColor = 0.8 * gl_SecondaryColor; \n"
- " } \n"
-#else
- /* DEBUG CODE */
- " bool f = gl_FrontFacing; \n"
- " if (f) { \n"
- " gl_FragColor = vec4(1.0, 0.0, 0.0, 0.0); \n"
- " } \n"
- " else { \n"
- " gl_FragColor = vec4(0.0, 1.0, 0.0, 0.0); \n"
- " } \n"
-#endif
- "} \n";
- static const char *vertShaderText =
- "uniform bool fragface; \n"
- "void main() { \n"
- " gl_FrontColor = gl_Color; \n"
- " if (fragface) { \n"
- " // front/back chosen in frag prog \n"
- " gl_FrontSecondaryColor = gl_SecondaryColor; \n"
- " } \n"
- " else { \n"
- " // front/back chosen in prim setup \n"
- " gl_BackColor = gl_SecondaryColor; \n"
- " } \n"
- " gl_Position = ftransform(); \n"
- "} \n";
-
- if (!ShadersSupported())
- exit(1);
-
- vertShader = CompileShaderText(GL_VERTEX_SHADER, vertShaderText);
- fragShader = CompileShaderText(GL_FRAGMENT_SHADER, fragShaderText);
- program = LinkShaders(vertShader, fragShader);
-
- glUseProgram(program);
-
- u_fragface = glGetUniformLocation(program, "fragface");
- printf("Uniforms: %d\n", u_fragface);
-
- /*assert(glGetError() == 0);*/
-
- glClearColor(0.3f, 0.3f, 0.3f, 0.0f);
-
- printf("GL_RENDERER = %s\n",(const char *) glGetString(GL_RENDERER));
-
- assert(glIsProgram(program));
- assert(glIsShader(fragShader));
- assert(glIsShader(vertShader));
-
- glEnable(GL_DEPTH_TEST);
-
- SetDefaults();
-}
-
-
-static void
-ParseOptions(int argc, char *argv[])
-{
- int i;
- for (i = 1; i < argc; i++) {
- if (strcmp(argv[i], "-fs") == 0) {
- FragProgFile = argv[i+1];
- }
- else if (strcmp(argv[i], "-vs") == 0) {
- VertProgFile = argv[i+1];
- }
- }
-}
-
-
-static void
-Usage(void)
-{
- printf("Keys:\n");
- printf(" f - do front/back determination in fragment shader\n");
- printf(" v - do front/back determination in vertex shader\n");
- printf(" r - reset, show front\n");
- printf(" a - toggle animation\n");
- printf(" s - step rotation\n");
- printf(" w - toggle CW, CCW front-face winding\n");
- printf("NOTE: red = front face, green = back face.\n");
-}
-
-
-int
-main(int argc, char *argv[])
-{
- glutInit(&argc, argv);
- glutInitWindowSize(WinWidth, WinHeight);
- glutInitDisplayMode(GLUT_RGB | GLUT_DEPTH | GLUT_DOUBLE);
- win = glutCreateWindow(argv[0]);
- glewInit();
- glutReshapeFunc(Reshape);
- glutKeyboardFunc(Key);
- glutDisplayFunc(Redisplay);
- if (anim)
- glutIdleFunc(Idle);
- ParseOptions(argc, argv);
- Init();
- Usage();
- glutMainLoop();
- return 0;
-}
projects / mesa.git / blobdiff