diff options
-rw-r--r-- | progs/demos/fogcoord.c | 364 |
1 files changed, 185 insertions, 179 deletions
diff --git a/progs/demos/fogcoord.c b/progs/demos/fogcoord.c index 19a15f05b87..00c73c6f048 100644 --- a/progs/demos/fogcoord.c +++ b/progs/demos/fogcoord.c @@ -7,151 +7,136 @@ * Daniel Borca */ - +#define GL_GLEXT_PROTOTYPES #include <stdio.h> #include <stdlib.h> #include <math.h> #include <GL/glut.h> -#include "readtex.h" - -#define TEXTURE_FILE "../images/bw.rgb" - -#define ARRAYS 0 /* use glDrawElements */ - -#define VERBOSE 1 /* tell me what happens */ +#define DEPTH 5.0f -#define DEPTH 15.0f +static PFNGLFOGCOORDFEXTPROC glFogCoordf_ext; +static PFNGLFOGCOORDPOINTEREXTPROC glFogCoordPointer_ext; -#if !defined(GLAPIENTRYP) -# define GLAPIENTRYP * -#endif - -typedef void (GLAPIENTRYP GLFOGCOORDFEXTPROC) (GLfloat f); -typedef void (GLAPIENTRYP GLFOGCOORDPOINTEREXTPROC) (GLenum, GLsizei, const GLvoid *); - -static GLFOGCOORDFEXTPROC glFogCoordf_ext; -#if ARRAYS -static GLFOGCOORDPOINTEREXTPROC glFogCoordPointer_ext; -#endif static GLboolean have_fog_coord; static GLfloat camz; -static GLuint texture[1]; static GLint fogMode; static GLboolean fogCoord; static GLfloat fogDensity = 0.75; -static GLfloat fogStart = 1.0, fogEnd = 40.0; +static GLfloat fogStart = 1.0, fogEnd = DEPTH; static GLfloat fogColor[4] = {0.6f, 0.3f, 0.0f, 1.0f}; +static const char *ModeStr = NULL; +static GLboolean Arrays = GL_FALSE; +static GLboolean Texture = GL_TRUE; -static void APIENTRY glFogCoordf_nop (GLfloat f) +static void +Reset(void) { - (void)f; + fogMode = 1; + fogCoord = 1; + fogDensity = 0.75; + fogStart = 1.0; + fogEnd = DEPTH; + Arrays = GL_FALSE; + Texture = GL_TRUE; } -static int BuildTexture (const char *filename, GLuint texid[]) +static void APIENTRY +glFogCoordf_nop (GLfloat f) { - GLubyte *tex_data; - GLenum tex_format; - GLint tex_width, tex_height; + (void)f; +} - tex_data = LoadRGBImage(filename, &tex_width, &tex_height, &tex_format); - if (tex_data == NULL) { - return -1; - } - { - GLint tex_max; - glGetIntegerv(GL_MAX_TEXTURE_SIZE, &tex_max); - if ((tex_width > tex_max) || (tex_height > tex_max)) { - return -1; - } +static void +PrintString(const char *s) +{ + while (*s) { + glutBitmapCharacter(GLUT_BITMAP_8_BY_13, (int) *s); + s++; } +} - glGenTextures(1, texid); - - glBindTexture(GL_TEXTURE_2D, texid[0]); - glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); - glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); - - glTexImage2D(GL_TEXTURE_2D, 0, tex_format, tex_width, tex_height, 0, - tex_format, GL_UNSIGNED_BYTE, tex_data); - return 0; +static void +PrintInfo(void) +{ + char s[100]; + + glDisable(GL_FOG); + glColor3f(0, 1, 1); + + sprintf(s, "Mode(m): %s Start(s/S): %g End(e/E): %g Density(d/D): %g", + ModeStr, fogStart, fogEnd, fogDensity); + glWindowPos2iARB(5, 20); + PrintString(s); + + sprintf(s, "Arrays(a): %s glFogCoord(c): %s EyeZ(z/z): %g", + (Arrays ? "Yes" : "No"), + (fogCoord ? "Yes" : "No"), + camz); + glWindowPos2iARB(5, 5); + PrintString(s); } -static int SetFogMode (GLint fogMode) +static int +SetFogMode(GLint fogMode) { fogMode &= 3; switch (fogMode) { case 0: + ModeStr = "Off"; glDisable(GL_FOG); -#if VERBOSE - printf("fog(disable)\n"); -#endif break; case 1: + ModeStr = "GL_LINEAR"; glEnable(GL_FOG); glFogi(GL_FOG_MODE, GL_LINEAR); glFogf(GL_FOG_START, fogStart); glFogf(GL_FOG_END, fogEnd); -#if VERBOSE - printf("fog(GL_LINEAR, %.2f, %.2f)\n", fogStart, fogEnd); -#endif break; case 2: + ModeStr = "GL_EXP"; glEnable(GL_FOG); glFogi(GL_FOG_MODE, GL_EXP); glFogf(GL_FOG_DENSITY, fogDensity); -#if VERBOSE - printf("fog(GL_EXP, %.2f)\n", fogDensity); -#endif break; case 3: + ModeStr = "GL_EXP2"; glEnable(GL_FOG); glFogi(GL_FOG_MODE, GL_EXP2); glFogf(GL_FOG_DENSITY, fogDensity); -#if VERBOSE - printf("fog(GL_EXP2, %.2f)\n", fogDensity); -#endif break; } return fogMode; } -static GLboolean SetFogCoord (GLboolean fogCoord) +static GLboolean +SetFogCoord(GLboolean fogCoord) { glFogCoordf_ext = glFogCoordf_nop; if (!have_fog_coord) { -#if VERBOSE - printf("fog(GL_FRAGMENT_DEPTH_EXT)%s\n", fogCoord ? " EXT_fog_coord not available!" : ""); -#endif return GL_FALSE; } if (fogCoord) { - glFogCoordf_ext = (GLFOGCOORDFEXTPROC)glutGetProcAddress("glFogCoordfEXT"); + glFogCoordf_ext = (PFNGLFOGCOORDFEXTPROC)glutGetProcAddress("glFogCoordfEXT"); glFogi(GL_FOG_COORDINATE_SOURCE_EXT, GL_FOG_COORDINATE_EXT); -#if VERBOSE - printf("fog(GL_FOG_COORDINATE_EXT)\n"); -#endif - } else { + } + else { glFogi(GL_FOG_COORDINATE_SOURCE_EXT, GL_FRAGMENT_DEPTH_EXT); -#if VERBOSE - printf("fog(GL_FRAGMENT_DEPTH_EXT)\n"); -#endif } return fogCoord; } -#if ARRAYS /* could reuse vertices */ static GLuint vertex_index[] = { /* Back */ @@ -172,19 +157,19 @@ static GLuint vertex_index[] = { static GLfloat vertex_pointer[][3] = { /* Back */ - {-2.5f,-2.5f,-DEPTH}, { 2.5f,-2.5f,-DEPTH}, { 2.5f, 2.5f,-DEPTH}, {-2.5f, 2.5f,-DEPTH}, + {-1.0f,-1.0f,-DEPTH}, { 1.0f,-1.0f,-DEPTH}, { 1.0f, 1.0f,-DEPTH}, {-1.0f, 1.0f,-DEPTH}, /* Floor */ - {-2.5f,-2.5f,-DEPTH}, { 2.5f,-2.5f,-DEPTH}, { 2.5f,-2.5f, DEPTH}, {-2.5f,-2.5f, DEPTH}, + {-1.0f,-1.0f,-DEPTH}, { 1.0f,-1.0f,-DEPTH}, { 1.0f,-1.0f, 0.0}, {-1.0f,-1.0f, 0.0}, /* Roof */ - {-2.5f, 2.5f,-DEPTH}, { 2.5f, 2.5f,-DEPTH}, { 2.5f, 2.5f, DEPTH}, {-2.5f, 2.5f, DEPTH}, + {-1.0f, 1.0f,-DEPTH}, { 1.0f, 1.0f,-DEPTH}, { 1.0f, 1.0f, 0.0}, {-1.0f, 1.0f, 0.0}, /* Right */ - { 2.5f,-2.5f, DEPTH}, { 2.5f, 2.5f, DEPTH}, { 2.5f, 2.5f,-DEPTH}, { 2.5f,-2.5f,-DEPTH}, + { 1.0f,-1.0f, 0.0}, { 1.0f, 1.0f, 0.0}, { 1.0f, 1.0f,-DEPTH}, { 1.0f,-1.0f,-DEPTH}, /* Left */ - {-2.5f,-2.5f, DEPTH}, {-2.5f, 2.5f, DEPTH}, {-2.5f, 2.5f,-DEPTH}, {-2.5f,-2.5f,-DEPTH} + {-1.0f,-1.0f, 0.0}, {-1.0f, 1.0f, 0.0}, {-1.0f, 1.0f,-DEPTH}, {-1.0f,-1.0f,-DEPTH} }; static GLfloat texcoord_pointer[][2] = { @@ -192,118 +177,139 @@ static GLfloat texcoord_pointer[][2] = { {0.0f, 0.0f}, {1.0f, 0.0f}, {1.0f, 1.0f}, {0.0f, 1.0f}, /* Floor */ - {0.0f, 0.0f}, {1.0f, 0.0f}, {1.0f, 1.0f}, {0.0f, 1.0f}, + {0.0f, 0.0f}, {1.0f, 0.0f}, {1.0f, DEPTH}, {0.0f, DEPTH}, /* Roof */ - {0.0f, 0.0f}, {1.0f, 0.0f}, {1.0f, 1.0f}, {0.0f, 1.0f}, + {1.0f, 0.0f}, {0.0f, 0.0f}, {0.0f, DEPTH}, {1.0f, DEPTH}, /* Right */ - {0.0f, 0.0f}, {0.0f, 1.0f}, {1.0f, 1.0f}, {1.0f, 0.0f}, + {0.0f, 1.0f}, {0.0f, 0.0f}, {DEPTH, 0.0f}, {DEPTH, 1.0f}, /* Left */ - {0.0f, 0.0f}, {0.0f, 1.0f}, {1.0f, 1.0f}, {1.0f, 0.0f} + {0.0f, 0.0f}, {0.0f, 1.0f}, {DEPTH, 1.0f}, {DEPTH, 0.0f} }; -static GLfloat fogcoord_pointer[][1] = { +static GLfloat fogcoord_pointer[] = { /* Back */ - {1.0f}, {1.0f}, {1.0f}, {1.0f}, + DEPTH, DEPTH, DEPTH, DEPTH, /* Floor */ - {1.0f}, {1.0f}, {0.0f}, {0.0f}, + DEPTH, DEPTH, 0.0, 0.0, /* Roof */ - {1.0f}, {1.0f}, {0.0f}, {0.0f}, + DEPTH, DEPTH, 0.0, 0.0, /* Right */ - {0.0f}, {0.0f}, {1.0f}, {1.0f}, + 0.0, 0.0, DEPTH, DEPTH, /* Left */ - {0.0f}, {0.0f}, {1.0f}, {1.0f} + 0.0, 0.0, DEPTH, DEPTH }; -#endif -static void Display( void ) +static void +Display( void ) { glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glLoadIdentity (); - glTranslatef(0.0f, 0.0f, camz); + glTranslatef(0.0f, 0.0f, -camz); -#if ARRAYS - glDrawElements(GL_QUADS, sizeof(vertex_index) / sizeof(vertex_index[0]), GL_UNSIGNED_INT, vertex_index); -#else - /* Back */ - glBegin(GL_QUADS); - glFogCoordf_ext(1.0f); glTexCoord2f(0.0f, 0.0f); glVertex3f(-2.5f,-2.5f,-DEPTH); - glFogCoordf_ext(1.0f); glTexCoord2f(1.0f, 0.0f); glVertex3f( 2.5f,-2.5f,-DEPTH); - glFogCoordf_ext(1.0f); glTexCoord2f(1.0f, 1.0f); glVertex3f( 2.5f, 2.5f,-DEPTH); - glFogCoordf_ext(1.0f); glTexCoord2f(0.0f, 1.0f); glVertex3f(-2.5f, 2.5f,-DEPTH); - glEnd(); + SetFogMode(fogMode); - /* Floor */ - glBegin(GL_QUADS); - glFogCoordf_ext(1.0f); glTexCoord2f(0.0f, 0.0f); glVertex3f(-2.5f,-2.5f,-DEPTH); - glFogCoordf_ext(1.0f); glTexCoord2f(1.0f, 0.0f); glVertex3f( 2.5f,-2.5f,-DEPTH); - glFogCoordf_ext(0.0f); glTexCoord2f(1.0f, 1.0f); glVertex3f( 2.5f,-2.5f, DEPTH); - glFogCoordf_ext(0.0f); glTexCoord2f(0.0f, 1.0f); glVertex3f(-2.5f,-2.5f, DEPTH); - glEnd(); + glColor3f(1, 1, 1); - /* Roof */ - glBegin(GL_QUADS); - glFogCoordf_ext(1.0f); glTexCoord2f(0.0f, 0.0f); glVertex3f(-2.5f, 2.5f,-DEPTH); - glFogCoordf_ext(1.0f); glTexCoord2f(1.0f, 0.0f); glVertex3f( 2.5f, 2.5f,-DEPTH); - glFogCoordf_ext(0.0f); glTexCoord2f(1.0f, 1.0f); glVertex3f( 2.5f, 2.5f, DEPTH); - glFogCoordf_ext(0.0f); glTexCoord2f(0.0f, 1.0f); glVertex3f(-2.5f, 2.5f, DEPTH); - glEnd(); + if (Texture) + glEnable(GL_TEXTURE_2D); - /* Right */ - glBegin(GL_QUADS); - glFogCoordf_ext(0.0f); glTexCoord2f(0.0f, 0.0f); glVertex3f( 2.5f,-2.5f, DEPTH); - glFogCoordf_ext(0.0f); glTexCoord2f(0.0f, 1.0f); glVertex3f( 2.5f, 2.5f, DEPTH); - glFogCoordf_ext(1.0f); glTexCoord2f(1.0f, 1.0f); glVertex3f( 2.5f, 2.5f,-DEPTH); - glFogCoordf_ext(1.0f); glTexCoord2f(1.0f, 0.0f); glVertex3f( 2.5f,-2.5f,-DEPTH); - glEnd(); + if (Arrays) { + glEnableClientState(GL_VERTEX_ARRAY); + glEnableClientState(GL_TEXTURE_COORD_ARRAY); + glDrawElements(GL_QUADS, sizeof(vertex_index) / sizeof(vertex_index[0]), + GL_UNSIGNED_INT, vertex_index); + glDisableClientState(GL_VERTEX_ARRAY); + glDisableClientState(GL_TEXTURE_COORD_ARRAY); + } + else { + /* Back */ + glBegin(GL_QUADS); + glFogCoordf_ext(DEPTH); glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f,-1.0f,-DEPTH); + glFogCoordf_ext(DEPTH); glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f,-1.0f,-DEPTH); + glFogCoordf_ext(DEPTH); glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f, 1.0f,-DEPTH); + glFogCoordf_ext(DEPTH); glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f,-DEPTH); + glEnd(); + + /* Floor */ + glBegin(GL_QUADS); + glFogCoordf_ext(DEPTH); glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f,-1.0f,-DEPTH); + glFogCoordf_ext(DEPTH); glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f,-1.0f,-DEPTH); + glFogCoordf_ext(0.0f); glTexCoord2f(1.0f, DEPTH); glVertex3f( 1.0f,-1.0f,0.0); + glFogCoordf_ext(0.0f); glTexCoord2f(0.0f, DEPTH); glVertex3f(-1.0f,-1.0f,0.0); + glEnd(); + + /* Roof */ + glBegin(GL_QUADS); + glFogCoordf_ext(DEPTH); glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, 1.0f,-DEPTH); + glFogCoordf_ext(DEPTH); glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, 1.0f,-DEPTH); + glFogCoordf_ext(0.0f); glTexCoord2f(0.0f, DEPTH); glVertex3f( 1.0f, 1.0f,0.0); + glFogCoordf_ext(0.0f); glTexCoord2f(1.0f, DEPTH); glVertex3f(-1.0f, 1.0f,0.0); + glEnd(); + + /* Right */ + glBegin(GL_QUADS); + glFogCoordf_ext(0.0f); glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f,-1.0f,0.0); + glFogCoordf_ext(0.0f); glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, 1.0f,0.0); + glFogCoordf_ext(DEPTH); glTexCoord2f(DEPTH, 0.0f); glVertex3f( 1.0f, 1.0f,-DEPTH); + glFogCoordf_ext(DEPTH); glTexCoord2f(DEPTH, 1.0f); glVertex3f( 1.0f,-1.0f,-DEPTH); + glEnd(); + + /* Left */ + glBegin(GL_QUADS); + glFogCoordf_ext(0.0f); glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f,-1.0f,0.0); + glFogCoordf_ext(0.0f); glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f,0.0); + glFogCoordf_ext(DEPTH); glTexCoord2f(DEPTH, 1.0f); glVertex3f(-1.0f, 1.0f,-DEPTH); + glFogCoordf_ext(DEPTH); glTexCoord2f(DEPTH, 0.0f); glVertex3f(-1.0f,-1.0f,-DEPTH); + glEnd(); + } - /* Left */ - glBegin(GL_QUADS); - glFogCoordf_ext(0.0f); glTexCoord2f(0.0f, 0.0f); glVertex3f(-2.5f,-2.5f, DEPTH); - glFogCoordf_ext(0.0f); glTexCoord2f(0.0f, 1.0f); glVertex3f(-2.5f, 2.5f, DEPTH); - glFogCoordf_ext(1.0f); glTexCoord2f(1.0f, 1.0f); glVertex3f(-2.5f, 2.5f,-DEPTH); - glFogCoordf_ext(1.0f); glTexCoord2f(1.0f, 0.0f); glVertex3f(-2.5f,-2.5f,-DEPTH); - glEnd(); -#endif + glDisable(GL_TEXTURE_2D); + + PrintInfo(); glutSwapBuffers(); } -static void Reshape( int width, int height ) +static void +Reshape( int width, int height ) { glViewport(0, 0, width, height); glMatrixMode(GL_PROJECTION); glLoadIdentity(); - gluPerspective(45.0f, (GLfloat)(width)/(GLfloat)(height), 0.1f, 100.0f); + glFrustum(-1, 1, -1, 1, 1.0, 100); glMatrixMode(GL_MODELVIEW); glLoadIdentity(); } -static void Key( unsigned char key, int x, int y ) +static void +Key( unsigned char key, int x, int y ) { (void) x; (void) y; switch (key) { + case 'a': + Arrays = !Arrays; + break; case 'f': + case 'm': fogMode = SetFogMode(fogMode + 1); break; - case '+': - if (fogDensity < 1.0) { - fogDensity += 0.05; - } + case 'D': + fogDensity += 0.05; SetFogMode(fogMode); break; - case '-': + case 'd': if (fogDensity > 0.0) { fogDensity -= 0.05; } @@ -311,31 +317,43 @@ static void Key( unsigned char key, int x, int y ) break; case 's': if (fogStart > 0.0) { - fogStart -= 1.0; + fogStart -= 0.25; } SetFogMode(fogMode); break; case 'S': - if (fogStart < fogEnd) { - fogStart += 1.0; + if (fogStart < 100.0) { + fogStart += 0.25; } SetFogMode(fogMode); break; case 'e': - if (fogEnd > fogStart) { - fogEnd -= 1.0; + if (fogEnd > 0.0) { + fogEnd -= 0.25; } SetFogMode(fogMode); break; case 'E': if (fogEnd < 100.0) { - fogEnd += 1.0; + fogEnd += 0.25; } SetFogMode(fogMode); break; case 'c': fogCoord = SetFogCoord(fogCoord ^ GL_TRUE); break; + case 't': + Texture = !Texture; + break; + case 'z': + camz -= 0.1; + break; + case 'Z': + camz += 0.1; + break; + case 'r': + Reset(); + break; case 27: exit(0); break; @@ -344,37 +362,28 @@ static void Key( unsigned char key, int x, int y ) } -static void SpecialKey( int key, int x, int y ) +static void +Init(void) { - (void) x; - (void) y; - switch (key) { - case GLUT_KEY_UP: - if (camz < (DEPTH - 1.0)) { - camz += 1.0f; - } - break; - case GLUT_KEY_DOWN: - if (camz > -19.0) { - camz -= 1.0f; - } - break; - } - glutPostRedisplay(); -} + static const GLubyte teximage[2][2][4] = { + { { 255, 255, 255, 255}, { 128, 128, 128, 255} }, + { { 128, 128, 128, 255}, { 255, 255, 255, 255} } + }; + printf("GL_RENDERER = %s\n", (char *) glGetString(GL_RENDERER)); -static void Init( void ) -{ have_fog_coord = glutExtensionSupported("GL_EXT_fog_coord"); - - if (BuildTexture(TEXTURE_FILE, texture) == -1) { - exit(1); + if (!have_fog_coord) { + printf("GL_EXT_fog_coord not supported!\n"); } - glEnable(GL_TEXTURE_2D); - glClearColor(0.0f, 0.0f, 0.0f, 0.5f); - glClearDepth(1.0f); + glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, 2, 2, 0, + GL_RGBA, GL_UNSIGNED_BYTE, teximage); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST); + + glClearColor(0.1f, 0.1f, 0.1f, 0.0f); + glDepthFunc(GL_LEQUAL); glEnable(GL_DEPTH_TEST); glShadeModel(GL_SMOOTH); @@ -383,11 +392,8 @@ static void Init( void ) glFogfv(GL_FOG_COLOR, fogColor); glHint(GL_FOG_HINT, GL_NICEST); fogCoord = SetFogCoord(GL_TRUE); /* try to enable fog_coord */ - fogMode = SetFogMode(2); /* GL_EXP */ - - camz = -19.0f; + fogMode = SetFogMode(1); -#if ARRAYS glEnableClientState(GL_VERTEX_ARRAY); glVertexPointer(3, GL_FLOAT, 0, vertex_pointer); @@ -395,24 +401,24 @@ static void Init( void ) glTexCoordPointer(2, GL_FLOAT, 0, texcoord_pointer); if (have_fog_coord) { - glFogCoordPointer_ext = (GLFOGCOORDPOINTEREXTPROC)glutGetProcAddress("glFogCoordPointerEXT"); + glFogCoordPointer_ext = (PFNGLFOGCOORDPOINTEREXTPROC)glutGetProcAddress("glFogCoordPointerEXT"); glEnableClientState(GL_FOG_COORDINATE_ARRAY_EXT); glFogCoordPointer_ext(GL_FLOAT, 0, fogcoord_pointer); } -#endif + + Reset(); } -int main( int argc, char *argv[] ) +int +main( int argc, char *argv[] ) { glutInit( &argc, argv ); - glutInitWindowPosition( 0, 0 ); - glutInitWindowSize( 640, 480 ); + glutInitWindowSize( 600, 600 ); glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH ); glutCreateWindow(argv[0]); glutReshapeFunc( Reshape ); glutKeyboardFunc( Key ); - glutSpecialFunc( SpecialKey ); glutDisplayFunc( Display ); Init(); glutMainLoop(); |