netgen/ng/Togl2.1/texture.c
2016-02-08 15:53:16 +01:00

664 lines
16 KiB
C

/* $Id: texture.c,v 1.14 2007/08/03 16:48:50 gregcouch Exp $ */
/*
* Togl - a Tk OpenGL widget
* Copyright (C) 1996-1997 Brian Paul and Ben Bederson
* Copyright (C) 2006-2007 Greg Couch
* See the LICENSE file for copyright details.
*/
/*
* An example Togl program demonstrating texture mapping
*/
#define USE_TOGL_STUBS
#include "togl.h"
#include <stdlib.h>
#include <string.h>
#if defined(TOGL_AGL)
# include <OpenGL/glu.h>
#else
# include <GL/glu.h>
#endif
#include "image.h"
#undef TCL_STORAGE_CLASS
#define TCL_STORAGE_CLASS DLLEXPORT
#define CHECKER 0
#define FACE 1
#define TREE 2
static GLenum minfilter = GL_NEAREST_MIPMAP_LINEAR;
static GLenum magfilter = GL_LINEAR;
static GLenum swrap = GL_REPEAT;
static GLenum twrap = GL_REPEAT;
static GLenum envmode = GL_MODULATE;
static GLubyte polycolor[4] = { 255, 255, 255, 255 };
static int teximage = CHECKER;
static double coord_scale = 1;
static double xrot = 0;
static double yrot = 0;
static double texscale = 1;
static GLint width, height;
static GLboolean blend = GL_FALSE;
/*
* Load a texture image. n is one of CHECKER, FACE or TREE.
*/
static void
texture_image(int n)
{
if (n == CHECKER) {
#define WIDTH 64
#define HEIGHT 64
GLubyte teximage[WIDTH * HEIGHT][4];
int i, j;
for (i = 0; i < HEIGHT; i++) {
for (j = 0; j < WIDTH; j++) {
GLubyte value;
value = ((i / 4 + j / 4) % 2) ? 0xff : 0x00;
teximage[i * WIDTH + j][0] = value;
teximage[i * WIDTH + j][1] = value;
teximage[i * WIDTH + j][2] = value;
teximage[i * WIDTH + j][3] = value;
}
}
glEnable(GL_TEXTURE_2D);
gluBuild2DMipmaps(GL_TEXTURE_2D, 4, WIDTH, HEIGHT,
GL_RGBA, GL_UNSIGNED_BYTE, teximage);
blend = GL_FALSE;
#undef WIDTH
#undef HEIGHT
} else if (n == FACE) {
TK_RGBImageRec *img = tkRGBImageLoad("ben.rgb");
if (img) {
glEnable(GL_TEXTURE_2D);
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
gluBuild2DMipmaps(GL_TEXTURE_2D, img->sizeZ, img->sizeX, img->sizeY,
img->sizeZ == 3 ? GL_RGB : GL_RGBA,
GL_UNSIGNED_BYTE, img->data);
blend = GL_TRUE;
}
} else if (n == TREE) {
TK_RGBImageRec *img = tkRGBImageLoad("tree2.rgba");
if (img) {
glEnable(GL_TEXTURE_2D);
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
gluBuild2DMipmaps(GL_TEXTURE_2D, img->sizeZ, img->sizeX, img->sizeY,
img->sizeZ == 3 ? GL_RGB : GL_RGBA,
GL_UNSIGNED_BYTE, img->data);
blend = GL_TRUE;
}
} else {
abort();
}
}
/*
* Togl widget create callback. This is called by Tcl/Tk when the widget has
* been realized. Here's where one may do some one-time context setup or
* initializations.
*/
static int
create_cb(ClientData clientData, Tcl_Interp *interp, int objc,
Tcl_Obj *const *objv)
{
glEnable(GL_DEPTH_TEST); /* Enable depth buffering */
texture_image(CHECKER);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, magfilter);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, minfilter);
return TCL_OK;
}
/*
* Togl widget reshape callback. This is called by Tcl/Tk when the widget
* has been resized. Typically, we call glViewport and perhaps setup the
* projection matrix.
*/
static int
reshape_cb(ClientData clientData, Tcl_Interp *interp, int objc,
Tcl_Obj *const *objv)
{
Togl *togl;
if (objc != 2) {
Tcl_WrongNumArgs(interp, 1, objv, "pathName");
return TCL_ERROR;
}
if (Togl_GetToglFromObj(interp, objv[1], &togl) != TCL_OK) {
return TCL_ERROR;
}
width = Togl_Width(togl);
height = Togl_Height(togl);
glViewport(0, 0, width, height);
return TCL_OK;
}
static void
check_error(char *where)
{
GLenum error;
while (1) {
error = glGetError();
if (error == GL_NO_ERROR) {
break;
}
printf("OpenGL error near %s: %s\n", where, gluErrorString(error));
}
}
/*
* Togl widget display callback. This is called by Tcl/Tk when the widget's
* contents have to be redrawn. Typically, we clear the color and depth
* buffers, render our objects, then swap the front/back color buffers.
*/
static int
display_cb(ClientData clientData, Tcl_Interp *interp, int objc,
Tcl_Obj *const *objv)
{
float aspect = (float) width / (float) height;
Togl *togl;
if (objc != 2) {
Tcl_WrongNumArgs(interp, 1, objv, "pathName");
return TCL_ERROR;
}
if (Togl_GetToglFromObj(interp, objv[1], &togl) != TCL_OK) {
return TCL_ERROR;
}
check_error("begin display\n");
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
/* Draw background image */
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glDisable(GL_TEXTURE_2D);
glDisable(GL_DEPTH_TEST);
glBegin(GL_POLYGON);
glColor3f(0, 0, 0.3f);
glVertex2f(-1, -1);
glColor3f(0, 0, 0.3f);
glVertex2f(1, -1);
glColor3f(0, 0, 0.9f);
glVertex2f(1, 1);
glColor3f(0, 0, 0.9f);
glVertex2f(-1, 1);
glEnd();
/* draw textured object */
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glFrustum(-aspect, aspect, -1, 1, 2, 10);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glTranslatef(0, 0, -5);
glScaled(texscale, texscale, texscale);
glRotated(yrot, 0, 1, 0);
glRotated(xrot, 1, 0, 0);
glEnable(GL_DEPTH_TEST);
glEnable(GL_TEXTURE_2D);
glColor4ubv(polycolor);
if (blend) {
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glEnable(GL_BLEND);
}
glBegin(GL_POLYGON);
glTexCoord2f(0, 0);
glVertex2f(-1, -1);
glTexCoord2d(coord_scale, 0);
glVertex2f(1, -1);
glTexCoord2d(coord_scale, coord_scale);
glVertex2f(1, 1);
glTexCoord2d(0, coord_scale);
glVertex2f(-1, 1);
glEnd();
glDisable(GL_BLEND);
Togl_SwapBuffers(togl);
return TCL_OK;
}
/*
* Called when a magnification filter radio button is pressed.
*/
static int
magfilter_cmd(ClientData clientData, Tcl_Interp *interp, int objc,
Tcl_Obj *const *objv)
{
static const char *names[] = { "GL_NEAREST", "GL_LINEAR", NULL };
static const GLenum magfilters[] = { GL_NEAREST, GL_LINEAR };
int result, index;
Togl *togl;
if (objc != 3) {
Tcl_WrongNumArgs(interp, 1, objv, "pathName magnification-filter-type");
return TCL_ERROR;
}
if (Togl_GetToglFromObj(interp, objv[1], &togl) != TCL_OK) {
return TCL_ERROR;
}
result = Tcl_GetIndexFromObj(interp, objv[2], names,
"magnification filter type", 0, &index);
if (result == TCL_OK) {
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER,
magfilters[index]);
Togl_PostRedisplay(togl);
}
return result;
}
/*
* Called when a minification filter radio button is pressed.
*/
static int
minfilter_cmd(ClientData clientData, Tcl_Interp *interp, int objc,
Tcl_Obj *const *objv)
{
static const char *names[] = {
"GL_NEAREST", "GL_LINEAR",
"GL_NEAREST_MIPMAP_NEAREST", "GL_LINEAR_MIPMAP_NEAREST",
"GL_NEAREST_MIPMAP_LINEAR", "GL_LINEAR_MIPMAP_LINEAR", NULL
};
static const GLenum minfilters[] = {
GL_NEAREST, GL_LINEAR,
GL_NEAREST_MIPMAP_NEAREST, GL_LINEAR_MIPMAP_NEAREST,
GL_NEAREST_MIPMAP_LINEAR, GL_LINEAR_MIPMAP_LINEAR
};
int result, index;
Togl *togl;
if (objc != 3) {
Tcl_WrongNumArgs(interp, 1, objv, "pathName minification-filter-type");
return TCL_ERROR;
}
if (Togl_GetToglFromObj(interp, objv[1], &togl) != TCL_OK) {
return TCL_ERROR;
}
result = Tcl_GetIndexFromObj(interp, objv[2], names,
"minification filter type", 0, &index);
if (result == TCL_OK) {
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER,
minfilters[index]);
Togl_PostRedisplay(togl);
}
return result;
}
static int
xrot_cmd(ClientData clientData, Tcl_Interp *interp, int objc,
Tcl_Obj *const *objv)
{
Togl *togl;
if (objc != 3) {
Tcl_WrongNumArgs(interp, 1, objv, "pathName angle");
return TCL_ERROR;
}
if (Togl_GetToglFromObj(interp, objv[1], &togl) != TCL_OK) {
return TCL_ERROR;
}
if (Tcl_GetDoubleFromObj(interp, objv[2], &xrot) != TCL_OK) {
return TCL_ERROR;
}
Togl_PostRedisplay(togl);
/* Let result string equal value */
Tcl_SetObjResult(interp, objv[2]);
return TCL_OK;
}
static int
yrot_cmd(ClientData clientData, Tcl_Interp *interp, int objc,
Tcl_Obj *const *objv)
{
Togl *togl;
if (objc != 3) {
Tcl_WrongNumArgs(interp, 1, objv, "pathName angle");
return TCL_ERROR;
}
if (Togl_GetToglFromObj(interp, objv[1], &togl) != TCL_OK) {
return TCL_ERROR;
}
if (Tcl_GetDoubleFromObj(interp, objv[2], &yrot) != TCL_OK) {
return TCL_ERROR;
}
Togl_PostRedisplay(togl);
/* Let result string equal value */
Tcl_SetObjResult(interp, objv[2]);
return TCL_OK;
}
static int
texscale_cmd(ClientData clientData, Tcl_Interp *interp, int objc,
Tcl_Obj *const *objv)
{
Togl *togl;
if (objc != 3) {
Tcl_WrongNumArgs(interp, 1, objv, "pathName value");
return TCL_ERROR;
}
if (Togl_GetToglFromObj(interp, objv[1], &togl) != TCL_OK) {
return TCL_ERROR;
}
if (Tcl_GetDoubleFromObj(interp, objv[2], &texscale) != TCL_OK) {
return TCL_ERROR;
}
Togl_PostRedisplay(togl);
/* Let result string equal value */
Tcl_SetObjResult(interp, objv[2]);
return TCL_OK;
}
/*
* Called when S texture coordinate wrapping is changed.
*/
static int
swrap_cmd(ClientData clientData, Tcl_Interp *interp, int objc,
Tcl_Obj *const *objv)
{
static const char *names[] = { "GL_CLAMP", "GL_REPEAT", NULL };
static const GLenum swraps[] = { GL_CLAMP, GL_REPEAT };
int result, index;
Togl *togl;
if (objc != 3) {
Tcl_WrongNumArgs(interp, 1, objv, "pathName wrap-mode");
return TCL_ERROR;
}
if (Togl_GetToglFromObj(interp, objv[1], &togl) != TCL_OK) {
return TCL_ERROR;
}
result = Tcl_GetIndexFromObj(interp, objv[2], names,
"wrap mode", 0, &index);
if (result == TCL_OK) {
swrap = swraps[index];
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, swrap);
Togl_PostRedisplay(togl);
/* Let result string equal value */
Tcl_SetObjResult(interp, objv[2]);
}
return result;
}
/*
* Called when T texture coordinate wrapping is changed.
*/
static int
twrap_cmd(ClientData clientData, Tcl_Interp *interp, int objc,
Tcl_Obj *const *objv)
{
static const char *names[] = { "GL_CLAMP", "GL_REPEAT", NULL };
static const GLenum twraps[] = { GL_CLAMP, GL_REPEAT };
int result, index;
Togl *togl;
if (objc != 3) {
Tcl_WrongNumArgs(interp, 1, objv, "pathName wrap-mode");
return TCL_ERROR;
}
if (Togl_GetToglFromObj(interp, objv[1], &togl) != TCL_OK) {
return TCL_ERROR;
}
result = Tcl_GetIndexFromObj(interp, objv[2], names,
"wrap mode", 0, &index);
if (result == TCL_OK) {
twrap = twraps[index];
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, twrap);
Togl_PostRedisplay(togl);
/* Let result string equal value */
Tcl_SetObjResult(interp, objv[2]);
}
return result;
}
/*
* Called when the texture environment mode is changed.
*/
static int
envmode_cmd(ClientData clientData, Tcl_Interp *interp, int objc,
Tcl_Obj *const *objv)
{
static const char *names[] = {
"GL_MODULATE", "GL_DECAL", "GL_BLEND", NULL
};
static const GLenum envmodes[] = { GL_MODULATE, GL_DECAL, GL_BLEND };
int result, index;
Togl *togl;
if (objc != 3) {
Tcl_WrongNumArgs(interp, 1, objv, "pathName texture-env-mode");
return TCL_ERROR;
}
if (Togl_GetToglFromObj(interp, objv[1], &togl) != TCL_OK) {
return TCL_ERROR;
}
result = Tcl_GetIndexFromObj(interp, objv[2], names,
"texture env mode", 0, &index);
if (result == TCL_OK) {
envmode = envmodes[index];
glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, envmode);
Togl_PostRedisplay(togl);
/* Let result string equal value */
Tcl_SetObjResult(interp, objv[2]);
}
return result;
}
/*
* Called when the polygon color is changed.
*/
static int
polycolor_cmd(ClientData clientData, Tcl_Interp *interp, int objc,
Tcl_Obj *const *objv)
{
Togl *togl;
int r, g, b;
if (objc != 5) {
Tcl_WrongNumArgs(interp, 1, objv, "pathName r g b");
return TCL_ERROR;
}
if (Togl_GetToglFromObj(interp, objv[1], &togl) != TCL_OK) {
return TCL_ERROR;
}
if (Tcl_GetIntFromObj(interp, objv[2], &r) != TCL_OK
|| Tcl_GetIntFromObj(interp, objv[3], &g) != TCL_OK
|| Tcl_GetIntFromObj(interp, objv[4], &b) != TCL_OK) {
return TCL_ERROR;
}
polycolor[0] = r;
polycolor[1] = g;
polycolor[2] = b;
Togl_PostRedisplay(togl);
return TCL_OK;
}
/*
* Called when the texture image is to be changed
*/
static int
teximage_cmd(ClientData clientData, Tcl_Interp *interp, int objc,
Tcl_Obj *const *objv)
{
static const char *names[] = {
"CHECKER", "FACE", "TREE", NULL
};
static const GLenum teximages[] = {
CHECKER, FACE, TREE
};
int result, index;
Togl *togl;
if (objc != 3) {
Tcl_WrongNumArgs(interp, 1, objv, "pathName texture-image-name");
return TCL_ERROR;
}
if (Togl_GetToglFromObj(interp, objv[1], &togl) != TCL_OK) {
return TCL_ERROR;
}
result = Tcl_GetIndexFromObj(interp, objv[2], names,
"texture image name", 0, &index);
if (result == TCL_OK) {
teximage = teximages[index];
texture_image(teximage);
Togl_PostRedisplay(togl);
/* Let result string equal value */
Tcl_SetObjResult(interp, objv[2]);
}
return result;
}
/*
* Called when the texture coordinate scale is changed.
*/
static int
coord_scale_cmd(ClientData clientData, Tcl_Interp *interp, int objc,
Tcl_Obj *const *objv)
{
double s;
Togl *togl;
if (objc != 3) {
Tcl_WrongNumArgs(interp, 1, objv, "pathName scale");
return TCL_ERROR;
}
if (Togl_GetToglFromObj(interp, objv[1], &togl) != TCL_OK) {
return TCL_ERROR;
}
if (Tcl_GetDoubleFromObj(interp, objv[2], &s) != TCL_OK) {
return TCL_ERROR;
}
if (s > 0 && s < 10) {
coord_scale = s;
Togl_PostRedisplay(togl);
}
/* Let result string equal value */
Tcl_SetObjResult(interp, objv[2]);
return TCL_OK;
}
EXTERN int
Texture_Init(Tcl_Interp *interp)
{
/*
* Initialize Tcl and the Togl widget module.
*/
if (Tcl_InitStubs(interp, "8.1", 0) == NULL
|| Togl_InitStubs(interp, "2.0", 0) == NULL) {
return TCL_ERROR;
}
/*
* Specify the C callback functions for widget creation, display,
* and reshape.
*/
Tcl_CreateObjCommand(interp, "create_cb", create_cb, NULL, NULL);
Tcl_CreateObjCommand(interp, "display_cb", display_cb, NULL, NULL);
Tcl_CreateObjCommand(interp, "reshape_cb", reshape_cb, NULL, NULL);
/*
* Make a new Togl widget command so the Tcl code can set a C variable.
*/
Tcl_CreateObjCommand(interp, "min_filter", minfilter_cmd, NULL, NULL);
Tcl_CreateObjCommand(interp, "mag_filter", magfilter_cmd, NULL, NULL);
Tcl_CreateObjCommand(interp, "xrot", xrot_cmd, NULL, NULL);
Tcl_CreateObjCommand(interp, "yrot", yrot_cmd, NULL, NULL);
Tcl_CreateObjCommand(interp, "texscale", texscale_cmd, NULL, NULL);
Tcl_CreateObjCommand(interp, "swrap", swrap_cmd, NULL, NULL);
Tcl_CreateObjCommand(interp, "twrap", twrap_cmd, NULL, NULL);
Tcl_CreateObjCommand(interp, "envmode", envmode_cmd, NULL, NULL);
Tcl_CreateObjCommand(interp, "polycolor", polycolor_cmd, NULL, NULL);
Tcl_CreateObjCommand(interp, "teximage", teximage_cmd, NULL, NULL);
Tcl_CreateObjCommand(interp, "coord_scale", coord_scale_cmd, NULL, NULL);
/*
* Call Tcl_CreateCommand for application-specific commands, if
* they weren't already created by the init procedures called above.
*/
return TCL_OK;
}