| /** |
| * Test shadow2DRectProj() and shadow2D() functions. |
| * Brian Paul |
| * 11 April 2007 |
| */ |
| |
| #define GL_GLEXT_PROTOTYPES |
| #include <assert.h> |
| #include <string.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <math.h> |
| #include <GL/glew.h> |
| #include <GL/glut.h> |
| |
| |
| /** Use GL_RECTANGLE texture (with projective texcoords)? */ |
| #define USE_RECT 01 |
| |
| #define TEXSIZE 16 |
| |
| |
| static char *FragProgFile = NULL; |
| static char *VertProgFile = NULL; |
| |
| static GLuint fragShader; |
| static GLuint vertShader; |
| static GLuint program; |
| |
| static GLint uTexture2D; |
| static GLint uTextureRect; |
| |
| static GLint win = 0; |
| |
| static GLenum Filter = GL_LINEAR; |
| |
| static void |
| CheckError(int line) |
| { |
| GLenum err = glGetError(); |
| if (err) { |
| printf("GL Error %s (0x%x) at line %d\n", |
| gluErrorString(err), (int) err, line); |
| } |
| } |
| |
| |
| static void |
| PrintString(const char *s) |
| { |
| while (*s) { |
| glutBitmapCharacter(GLUT_BITMAP_8_BY_13, (int) *s); |
| s++; |
| } |
| } |
| |
| |
| static void |
| Redisplay(void) |
| { |
| CheckError(__LINE__); |
| glClear(GL_COLOR_BUFFER_BIT); |
| |
| glPushMatrix(); |
| |
| CheckError(__LINE__); |
| glUseProgram(program); |
| CheckError(__LINE__); |
| |
| glBegin(GL_POLYGON); |
| #if USE_RECT |
| /* scale coords by two to test projection */ |
| glTexCoord4f( 0, 0, 0, 2.0); glVertex2f(-1, -1); |
| glTexCoord4f(2*TEXSIZE, 0, 2*1, 2.0); glVertex2f( 1, -1); |
| glTexCoord4f(2*TEXSIZE, 2*TEXSIZE, 2*1, 2.0); glVertex2f( 1, 1); |
| glTexCoord4f( 0, 2*TEXSIZE, 0, 2.0); glVertex2f(-1, 1); |
| #else |
| glTexCoord3f(0, 0, 0); glVertex2f(-1, -1); |
| glTexCoord3f(1, 0, 1); glVertex2f( 1, -1); |
| glTexCoord3f(1, 1, 1); glVertex2f( 1, 1); |
| glTexCoord3f(0, 1, 0); glVertex2f(-1, 1); |
| #endif |
| glEnd(); |
| |
| glPopMatrix(); |
| |
| glUseProgram(0); |
| glWindowPos2iARB(80, 20); |
| PrintString("white black white black"); |
| |
| glutSwapBuffers(); |
| } |
| |
| |
| 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, -8.0f); |
| } |
| |
| |
| 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 27: |
| CleanUp(); |
| exit(0); |
| break; |
| } |
| glutPostRedisplay(); |
| } |
| |
| |
| static void |
| MakeTexture(void) |
| { |
| GLfloat image[TEXSIZE][TEXSIZE]; |
| GLuint i, j; |
| |
| for (i = 0; i < TEXSIZE; i++) { |
| for (j = 0; j < TEXSIZE; j++) { |
| if (j < (TEXSIZE / 2)) { |
| image[i][j] = 0.25; |
| } |
| else { |
| image[i][j] = 0.75; |
| } |
| } |
| } |
| |
| glActiveTexture(GL_TEXTURE0); /* unit 0 */ |
| glBindTexture(GL_TEXTURE_2D, 42); |
| glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT, TEXSIZE, TEXSIZE, 0, |
| GL_DEPTH_COMPONENT, GL_FLOAT, image); |
| glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAX_LEVEL, 1); |
| glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, Filter); |
| glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, Filter); |
| glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_MODE_ARB, |
| GL_COMPARE_R_TO_TEXTURE_ARB); |
| CheckError(__LINE__); |
| |
| glActiveTexture(GL_TEXTURE1); /* unit 1 */ |
| glBindTexture(GL_TEXTURE_RECTANGLE_ARB, 43); |
| glTexImage2D(GL_TEXTURE_RECTANGLE_ARB, 0, GL_DEPTH_COMPONENT, |
| TEXSIZE, 10, 0,/*16x10*/ |
| GL_DEPTH_COMPONENT, GL_FLOAT, image); |
| glTexParameteri(GL_TEXTURE_RECTANGLE_ARB, GL_TEXTURE_MIN_FILTER, Filter); |
| glTexParameteri(GL_TEXTURE_RECTANGLE_ARB, GL_TEXTURE_MAG_FILTER, Filter); |
| glTexParameteri(GL_TEXTURE_RECTANGLE_ARB, GL_TEXTURE_COMPARE_MODE_ARB, |
| GL_COMPARE_R_TO_TEXTURE_ARB); |
| CheckError(__LINE__); |
| } |
| |
| |
| static void |
| LoadAndCompileShader(GLuint shader, const char *text) |
| { |
| GLint stat; |
| glShaderSource(shader, 1, (const GLchar **) &text, NULL); |
| glCompileShader(shader); |
| glGetShaderiv(shader, GL_COMPILE_STATUS, &stat); |
| if (!stat) { |
| GLchar log[1000]; |
| GLsizei len; |
| glGetShaderInfoLog(shader, 1000, &len, log); |
| fprintf(stderr, "fslight: problem compiling shader:\n%s\n", log); |
| exit(1); |
| } |
| } |
| |
| |
| /** |
| * Read a shader from a file. |
| */ |
| static void |
| ReadShader(GLuint shader, const char *filename) |
| { |
| const int max = 100*1000; |
| int n; |
| char *buffer = (char*) malloc(max); |
| FILE *f = fopen(filename, "r"); |
| if (!f) { |
| fprintf(stderr, "fslight: Unable to open shader file %s\n", filename); |
| exit(1); |
| } |
| |
| n = fread(buffer, 1, max, f); |
| printf("fslight: read %d bytes from shader file %s\n", n, filename); |
| if (n > 0) { |
| buffer[n] = 0; |
| LoadAndCompileShader(shader, buffer); |
| } |
| |
| fclose(f); |
| free(buffer); |
| } |
| |
| |
| static void |
| CheckLink(GLuint prog) |
| { |
| GLint stat; |
| glGetProgramiv(prog, GL_LINK_STATUS, &stat); |
| if (!stat) { |
| GLchar log[1000]; |
| GLsizei len; |
| glGetProgramInfoLog(prog, 1000, &len, log); |
| fprintf(stderr, "Linker error:\n%s\n", log); |
| } |
| } |
| |
| |
| static void |
| Init(void) |
| { |
| static const char *fragShaderText = |
| "uniform sampler2DShadow shadowTex2D; \n" |
| "uniform sampler2DRectShadow shadowTexRect; \n" |
| "void main() {\n" |
| #if USE_RECT |
| " gl_FragColor = shadow2DRectProj(shadowTexRect, gl_TexCoord[0]); \n" |
| #else |
| " gl_FragColor = shadow2D(shadowTex2D, gl_TexCoord[0].xyz); \n" |
| #endif |
| "}\n"; |
| static const char *vertShaderText = |
| "void main() {\n" |
| " gl_Position = gl_ModelViewProjectionMatrix * gl_Vertex;\n" |
| " gl_TexCoord[0] = gl_MultiTexCoord0; \n" |
| "}\n"; |
| const char *version; |
| |
| #if USE_RECT |
| if (!glutExtensionSupported("GL_ARB_texture_rectangle")) { |
| printf("This program requires GL_ARB_texture_rectangle\n"); |
| exit(1); |
| } |
| #endif |
| |
| version = (const char *) glGetString(GL_VERSION); |
| if (version[0] != '2' || version[1] != '.') { |
| printf("This program requires OpenGL 2.x, found %s\n", version); |
| exit(1); |
| } |
| printf("GL_RENDERER = %s\n",(const char *) glGetString(GL_RENDERER)); |
| |
| fragShader = glCreateShader(GL_FRAGMENT_SHADER); |
| if (FragProgFile) |
| ReadShader(fragShader, FragProgFile); |
| else |
| LoadAndCompileShader(fragShader, fragShaderText); |
| |
| vertShader = glCreateShader(GL_VERTEX_SHADER); |
| if (VertProgFile) |
| ReadShader(vertShader, VertProgFile); |
| else |
| LoadAndCompileShader(vertShader, vertShaderText); |
| |
| program = glCreateProgram(); |
| glAttachShader(program, fragShader); |
| glAttachShader(program, vertShader); |
| glLinkProgram(program); |
| CheckLink(program); |
| glUseProgram(program); |
| |
| uTexture2D = glGetUniformLocation(program, "shadowTex2D"); |
| uTextureRect = glGetUniformLocation(program, "shadowTexRect"); |
| printf("uTexture2D %d uTextureRect %d\n", uTexture2D, uTextureRect); |
| if (uTexture2D >= 0) { |
| glUniform1i(uTexture2D, 0); /* use texture unit 0 */ |
| } |
| if (uTextureRect >= 0) { |
| glUniform1i(uTextureRect, 1); /* use texture unit 0 */ |
| } |
| CheckError(__LINE__); |
| |
| glClearColor(0.3f, 0.3f, 0.3f, 0.0f); |
| glColor3f(1, 1, 1); |
| |
| MakeTexture(); |
| CheckError(__LINE__); |
| } |
| |
| |
| 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]; |
| } |
| } |
| } |
| |
| |
| int |
| main(int argc, char *argv[]) |
| { |
| glutInit(&argc, argv); |
| glutInitWindowSize(400, 300); |
| glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE); |
| win = glutCreateWindow(argv[0]); |
| glewInit(); |
| glutReshapeFunc(Reshape); |
| glutKeyboardFunc(Key); |
| glutDisplayFunc(Redisplay); |
| ParseOptions(argc, argv); |
| Init(); |
| glutMainLoop(); |
| return 0; |
| } |
| |
| |