2025-04-27 07:49:33 -04:00

111 lines
2.9 KiB
C

#include "pch.c"
#pragma hdrstop
#include <math.h>
static GLfloat ctrlpoints[4][4][3] = {
{{ -1.5, -1.5, 4.0}, { -0.5, -1.5, 2.0},
{0.5, -1.5, -1.0}, {1.5, -1.5, 2.0}},
{{ -1.5, -0.5, 1.0}, { -0.5, -0.5, 3.0},
{0.5, -0.5, 0.0}, {1.5, -0.5, -1.0}},
{{ -1.5, 0.5, 4.0}, { -0.5, 0.5, 0.0},
{0.5, 0.5, 3.0}, {1.5, 0.5, 4.0}},
{{ -1.5, 1.5, -2.0}, { -0.5, 1.5, -2.0},
{0.5, 1.5, 0.0}, {1.5, 1.5, -1.0}}
};
static GLfloat texpts[2][2][2] = {{{0.0, 0.0}, {0.0, 1.0}},
{{1.0, 0.0}, {1.0, 1.0}}};
static void display(void)
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glColor3f(1.0, 1.0, 1.0);
glEvalMesh2(GL_FILL, 0, 20, 0, 20);
glFlush();
}
#define imageWidth 64
#define imageHeight 64
GLubyte image[3*imageWidth*imageHeight];
static void makeImage(void)
{
int i, j;
float ti, tj;
for (i = 0; i < imageWidth; i++) {
ti = 2.0*3.14159265*i/imageWidth;
for (j = 0; j < imageHeight; j++) {
tj = 2.0*3.14159265*j/imageHeight;
image[3*(imageHeight*i+j)] = (GLubyte) 127*(1.0+sin(ti));
image[3*(imageHeight*i+j)+1] = (GLubyte) 127*(1.0+cos(2*tj));
image[3*(imageHeight*i+j)+2] = (GLubyte) 127*(1.0+cos(ti+tj));
}
}
}
static void myinit(void)
{
glMap2f(GL_MAP2_VERTEX_3, 0, 1, 3, 4,
0, 1, 12, 4, &ctrlpoints[0][0][0]);
glMap2f(GL_MAP2_TEXTURE_COORD_2, 0, 1, 2, 2,
0, 1, 4, 2, &texpts[0][0][0]);
glEnable(GL_MAP2_TEXTURE_COORD_2);
glEnable(GL_MAP2_VERTEX_3);
glMapGrid2f(20, 0.0, 1.0, 20, 0.0, 1.0);
makeImage();
glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_DECAL);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexImage2D(GL_TEXTURE_2D, 0, 3, imageWidth, imageHeight, 0,
GL_RGB, GL_UNSIGNED_BYTE, image);
glEnable(GL_TEXTURE_2D);
glEnable(GL_DEPTH_TEST);
glEnable(GL_NORMALIZE);
glShadeModel (GL_FLAT);
}
static void myReshape(GLsizei w, GLsizei h)
{
glViewport(0, 0, w, h);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
if (w <= h)
glOrtho(-4.0, 4.0, -4.0*(GLfloat)h/(GLfloat)w,
4.0*(GLfloat)h/(GLfloat)w, -4.0, 4.0);
else
glOrtho(-4.0*(GLfloat)w/(GLfloat)h,
4.0*(GLfloat)w/(GLfloat)h, -4.0, 4.0, -4.0, 4.0);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glRotatef(85.0, 1.0, 1.0, 1.0);
}
#define WIDTH 300
#define HEIGHT 300
static void OglBounds(int *w, int *h)
{
*w = WIDTH;
*h = HEIGHT;
}
static void OglDraw(int w, int h)
{
myinit();
myReshape(w, h);
display();
}
OglModule oglmod_texsurf =
{
"texsurf",
NULL,
OglBounds,
NULL,
OglDraw
};