world_of_cow/mmn_17.c

273 lines
No EOL
8 KiB
C

#include <GL/freeglut.h>
#include <GL/freeglut_std.h>
#include <GL/gl.h>
#include <GL/glext.h>
#include <GL/glu.h>
#include <stdio.h>
#include <math.h>
#include "ui.h"
#include "grass_texture_color.h"
// close enough
#define PI 3.14
// Camera rotation and stuff
float camRadius = 10.0;
vec3 camCenter = { 0.0, 0.0, 0.0 };
vec3 camRot = { -PI * 0.125, 0.0, 0.0 };
struct {
unsigned char lockYMovement: 1;
GLenum textureFilter;
} settings = {
0, GL_NEAREST,
};
vec3 rotateByCameraRotation(vec3 v) {
vec3 r;
// rotate along the x axis(yz plane)
r.z = cosf(camRot.x) * v.z + sinf(camRot.x) * v.y;
r.y = -sinf(camRot.x) * v.z + cosf(camRot.x) * v.y;
v = r;
// rotate along the y axis(xy plane)
r.z = cosf(camRot.y) * v.z + sinf(camRot.y) * v.x;
r.x = -sinf(camRot.y) * v.z + cosf(camRot.y) * v.x;
return r;
}
// Ui stuff
int lastMouseButton = GLUT_LEFT_BUTTON;
int lastMouseX = 0, lastMouseY = 0;
ui_slider* draggedSlider = NULL;
void changeFilterButton();
void lockYButton();
ui_button buttons[] = {
{
/* pos */ { { 0.9, 0.5, 0.0 }, { -65.0, -20.0, 0.0 } },
/* size */ { 130.0, 40.0, 0.0 },
/* onclick */ changeFilterButton,
/* text */ "Cycle filter",
0
},
{
{ { 0.9, 0.5, 0.0 }, { -50.0, 25.0, 0.0 } },
{ 100.0, 40.0, 0.0 },
lockYButton,
"Lock Y"
}
};
ui_slider sliders[] = {
{
/* pos */ { { 0.9, 0.7, 0.0 }, { -50.0, -5.0, 0.0 } },
/* size */ { 100.0, 10.0, 10.0 },
0.1
}
};
void changeFilterButton() {
static int current = 0;
GLenum filters[] = { GL_NEAREST, GL_LINEAR };
current = (current + 1) % (sizeof(filters) / sizeof(GLenum));
settings.textureFilter = filters[current];
glutPostRedisplay();
}
void lockYButton() {
settings.lockYMovement ^= 1;
buttons[1].text = settings.lockYMovement ? "Unlock Y" : "Lock Y";
}
void drawUi(void) {
glDisable(GL_LIGHTING);
glDisable(GL_DEPTH_TEST);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
// set ui camera
int wWidth = glutGet(GLUT_WINDOW_WIDTH);
int wHeight = glutGet(GLUT_WINDOW_HEIGHT);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluOrtho2D(0.0, wWidth, 0.0, wHeight);
// Draw buttons
for(ui_button* b = buttons; b < buttons + sizeof buttons / sizeof(ui_button); b += 1) {
ui_button_draw(b);
}
for(ui_slider* s = sliders; s < sliders + sizeof sliders / sizeof(ui_slider); s += 1) {
ui_slider_draw(s);
}
int err = glGetError();
if(err != 0) {
printf("opengl error %d: %s\n", err, gluErrorString(err));
}
}
void drawWorld(void) {
glEnable(GL_DEPTH_TEST);
// set perspective camera
GLdouble wWidth = (GLdouble) glutGet(GLUT_WINDOW_WIDTH);
GLdouble wHeight = (GLdouble) glutGet(GLUT_WINDOW_HEIGHT);
// Calculate current camera position from rotation
vec3 cp = vec3_new(0.0, 0.0, camRadius);
cp = rotateByCameraRotation(cp);
cp = vec3_add(cp, camCenter);
vec3 up = rotateByCameraRotation(vec3_new(0.0, 1.0, 0.0));
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
gluLookAt(cp.x, cp.y, cp.z, camCenter.x, camCenter.y, camCenter.z, up.x, up.y, up.z);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(90, wWidth / wHeight , 1.0, 500.0);
// Lights
glEnable(GL_LIGHTING);
glEnable(GL_LIGHT0);
// Directional light - aka light
GLfloat light1[] = { 0.0, 1.0, 0.0, 0.0 };
glLightfv(GL_LIGHT0, GL_POSITION, light1);
// World
// Ground
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, settings.textureFilter);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, settings.textureFilter);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, 128, 128, 0, GL_RGBA, GL_UNSIGNED_BYTE, grass_color_128);
glEnable(GL_TEXTURE_2D);
glBegin(GL_QUADS);
glColor3f(1.0, 1.0, 0.0);
glNormal3f(0.0, 5.0, 0.0);
glTexCoord2f(0.0, 0.0); glVertex3f(-50.0, 0.0, -50.0);
glTexCoord2f(0.0, 1.0); glVertex3f(-50.0, 0.0, 50.0);
glTexCoord2f(1.0, 1.0); glVertex3f(50.0, 0.0, 50.0);
glTexCoord2f(1.0, 0.0); glVertex3f(50.0, 0.0, -50.0);
glEnd();
glDisable(GL_TEXTURE_2D);
glMatrixMode(GL_MODELVIEW);
glPushMatrix();
glTranslatef(0.0, 5.0, 0.0);
glScalef(3.0, 3.0, 3.0);
glColor3f(1.0, 1.0, 1.0);
glutSolidDodecahedron();
glPopMatrix();
}
void display(void) {
// Clear screen
glClearColor(0.0, 0.0, 0.0, 1.0); // Dark theme :)
glClear(GL_COLOR_BUFFER_BIT);
glClear(GL_DEPTH_BUFFER_BIT);
drawWorld();
drawUi();
glutSwapBuffers();
glFlush();
}
void mouseEvent(int button, int state, int x, int y) {
lastMouseX = x; lastMouseY = y;
if(state == 0) lastMouseButton = button;
if(state == 0 && button == GLUT_LEFT_BUTTON) {
for(ui_button* b = buttons; b < buttons + sizeof buttons / sizeof(ui_button); b += 1) {
if(ui_button_mouse_over(b, x, y) && b->onClick != NULL) {
b->clicked = 1;
}
}
for(ui_slider* s = sliders; s < sliders + sizeof sliders / sizeof(ui_slider); s += 1) {
if(ui_slider_mouse_over(s, x, y)) {
ui_slider_onclick(s, x, y);
draggedSlider = s;
}
}
}
else if(state == 1 && button == GLUT_LEFT_BUTTON) {
draggedSlider = NULL;
for(ui_button* b = buttons; b < buttons + sizeof buttons / sizeof(ui_button); b += 1) {
b->clicked = 0;
if(ui_button_mouse_over(b, x, y) && b->onClick != NULL) {
b->onClick();
}
}
}
glutPostRedisplay();
}
void mouseMotionEvent(int x, int y) {
if(lastMouseButton == GLUT_LEFT_BUTTON) {
if(draggedSlider != NULL) {
if(ui_slider_mouse_over(draggedSlider, x, y)) {
ui_slider_onclick(draggedSlider, x, y);
}
}
}
else if(lastMouseButton == GLUT_MIDDLE_BUTTON) {
vec3 moveX = rotateByCameraRotation(vec3_new(1.0, 0.0, 0.0));
vec3 moveY = rotateByCameraRotation(vec3_new(0.0, 1.0, 0.0));
if(settings.lockYMovement) {
moveX.y = 0;
moveY.y = 0;
}
camCenter = vec3_add(camCenter, vec3_mult(moveX, (lastMouseX - x)));
camCenter = vec3_add(camCenter, vec3_mult(moveY, (y - lastMouseY)));
}
else if(lastMouseButton == GLUT_RIGHT_BUTTON) {
// rotate the camera
camRot.y -= (x - lastMouseX) * PI * 0.01;
if(camRot.y > 2 * PI) camRot.y -= 2 * PI;
else if(camRot.y < 0.0) camRot.y += 2 * PI;
camRot.x = fmin(PI * 0.5, fmax(-PI * 0.5, camRot.x - (y - lastMouseY) * 0.01 * PI));
}
lastMouseX = x; lastMouseY = y;
glutPostRedisplay();
}
void mouseWheelEvent(int wheel, int dir, int x, int y) {
char slided = 0;
for(ui_slider* s = sliders; s < sliders + sizeof sliders / sizeof(ui_slider); s += 1) {
if(ui_slider_mouse_over(s, x, y)) {
s->value += dir * 0.05;
if(s->value < 0.0) s->value = 0.0;
if(s->value > 1.0) s->value = 1.0;
slided = 1;
}
}
if(!slided) {
camRadius *= 1.0 - (dir * 0.1);
}
glutPostRedisplay();
}
void keyboardEvent(unsigned char c, int x, int y) {
if(c == '\e') {
glutLeaveMainLoop();
exit(0);
}
if(c == 'a') {
glutPostRedisplay();
}
}
int main(int argc, char** argv) {
/* initialize glut and window */
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH);
glutInitWindowSize(800, 500);
glutInitWindowPosition(450, 450);
/* create window and set callbacks */
glutCreateWindow("World of Cow");
glutDisplayFunc(display);
glutMouseFunc(mouseEvent);
glutKeyboardFunc(keyboardEvent);
glutMouseWheelFunc(mouseWheelEvent);
glutMotionFunc(mouseMotionEvent);
// set up some rendering related stuff
glEnable(GL_CULL_FACE);
glCullFace(GL_BACK);
glutMainLoop();
return 0;
}