diff --git a/GNUmakefile b/GNUmakefile index c469583..b40c3d5 100644 --- a/GNUmakefile +++ b/GNUmakefile @@ -90,7 +90,7 @@ EXAMPLES = examples/example$(EXEC) examples/rotate$(EXEC) examples/image$(EXEC) ifeq ($(OPENGL),1) L_OBJS += src/widget/opengl.o -EXAMPLES += examples/opengl$(EXEC) +EXAMPLES += examples/opengl$(EXEC) examples/gears$(EXEC) endif ifeq ($(VULKAN),1) @@ -114,6 +114,9 @@ src/libMw$(SO): $(L_OBJS) examples/opengl$(EXEC): examples/opengl.o src/libMw$(SO) $(CC) $(E_LDFLAGS) -o $@ $< $(E_LIBS) $(GL) +examples/gears$(EXEC): examples/gears.o src/libMw$(SO) + $(CC) $(E_LDFLAGS) -o $@ $< $(E_LIBS) $(GL) + examples/%$(EXEC): examples/%.o src/libMw$(SO) $(CC) $(E_LDFLAGS) -o $@ $< $(E_LIBS) diff --git a/examples/gears.c b/examples/gears.c new file mode 100644 index 0000000..fcf9dae --- /dev/null +++ b/examples/gears.c @@ -0,0 +1,278 @@ +/* $Id$ */ +#include +#include + +#include + +MwWidget opengl; + +/* + * 3-D gear wheels. This program is in the public domain. + * + * Brian Paul + */ + +/* Conversion to GLUT by Mark J. Kilgard */ + +#include +#include + +#ifndef M_PI +#define M_PI 3.14159265 +#endif + +/** + + Draw a gear wheel. You'll probably want to call this function when + building a display list since we do a lot of trig here. + + Input: inner_radius - radius of hole at center + outer_radius - radius at center of teeth + width - width of gear + teeth - number of teeth + tooth_depth - depth of tooth + + **/ + +static void gear(GLfloat inner_radius, GLfloat outer_radius, GLfloat width, GLint teeth, GLfloat tooth_depth) { + GLint i; + GLfloat r0, r1, r2; + GLfloat angle, da; + GLfloat u, v, len; + + r0 = inner_radius; + r1 = outer_radius - tooth_depth / 2.0; + r2 = outer_radius + tooth_depth / 2.0; + + da = 2.0 * M_PI / teeth / 4.0; + + glShadeModel(GL_FLAT); + + glNormal3f(0.0, 0.0, 1.0); + + /* draw front face */ + glBegin(GL_QUAD_STRIP); + for(i = 0; i <= teeth; i++) { + angle = i * 2.0 * M_PI / teeth; + glVertex3f(r0 * cos(angle), r0 * sin(angle), width * 0.5); + glVertex3f(r1 * cos(angle), r1 * sin(angle), width * 0.5); + glVertex3f(r0 * cos(angle), r0 * sin(angle), width * 0.5); + glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da), width * 0.5); + } + glEnd(); + + /* draw front sides of teeth */ + glBegin(GL_QUADS); + da = 2.0 * M_PI / teeth / 4.0; + for(i = 0; i < teeth; i++) { + angle = i * 2.0 * M_PI / teeth; + + glVertex3f(r1 * cos(angle), r1 * sin(angle), width * 0.5); + glVertex3f(r2 * cos(angle + da), r2 * sin(angle + da), width * 0.5); + glVertex3f(r2 * cos(angle + 2 * da), r2 * sin(angle + 2 * da), width * 0.5); + glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da), width * 0.5); + } + glEnd(); + + glNormal3f(0.0, 0.0, -1.0); + + /* draw back face */ + glBegin(GL_QUAD_STRIP); + for(i = 0; i <= teeth; i++) { + angle = i * 2.0 * M_PI / teeth; + glVertex3f(r1 * cos(angle), r1 * sin(angle), -width * 0.5); + glVertex3f(r0 * cos(angle), r0 * sin(angle), -width * 0.5); + glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da), -width * 0.5); + glVertex3f(r0 * cos(angle), r0 * sin(angle), -width * 0.5); + } + glEnd(); + + /* draw back sides of teeth */ + glBegin(GL_QUADS); + da = 2.0 * M_PI / teeth / 4.0; + for(i = 0; i < teeth; i++) { + angle = i * 2.0 * M_PI / teeth; + + glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da), -width * 0.5); + glVertex3f(r2 * cos(angle + 2 * da), r2 * sin(angle + 2 * da), -width * 0.5); + glVertex3f(r2 * cos(angle + da), r2 * sin(angle + da), -width * 0.5); + glVertex3f(r1 * cos(angle), r1 * sin(angle), -width * 0.5); + } + glEnd(); + + /* draw outward faces of teeth */ + glBegin(GL_QUAD_STRIP); + for(i = 0; i < teeth; i++) { + angle = i * 2.0 * M_PI / teeth; + + glVertex3f(r1 * cos(angle), r1 * sin(angle), width * 0.5); + glVertex3f(r1 * cos(angle), r1 * sin(angle), -width * 0.5); + u = r2 * cos(angle + da) - r1 * cos(angle); + v = r2 * sin(angle + da) - r1 * sin(angle); + len = sqrt(u * u + v * v); + u /= len; + v /= len; + glNormal3f(v, -u, 0.0); + glVertex3f(r2 * cos(angle + da), r2 * sin(angle + da), width * 0.5); + glVertex3f(r2 * cos(angle + da), r2 * sin(angle + da), -width * 0.5); + glNormal3f(cos(angle), sin(angle), 0.0); + glVertex3f(r2 * cos(angle + 2 * da), r2 * sin(angle + 2 * da), width * 0.5); + glVertex3f(r2 * cos(angle + 2 * da), r2 * sin(angle + 2 * da), -width * 0.5); + u = r1 * cos(angle + 3 * da) - r2 * cos(angle + 2 * da); + v = r1 * sin(angle + 3 * da) - r2 * sin(angle + 2 * da); + glNormal3f(v, -u, 0.0); + glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da), width * 0.5); + glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da), -width * 0.5); + glNormal3f(cos(angle), sin(angle), 0.0); + } + + glVertex3f(r1 * cos(0), r1 * sin(0), width * 0.5); + glVertex3f(r1 * cos(0), r1 * sin(0), -width * 0.5); + + glEnd(); + + glShadeModel(GL_SMOOTH); + + /* draw inside radius cylinder */ + glBegin(GL_QUAD_STRIP); + for(i = 0; i <= teeth; i++) { + angle = i * 2.0 * M_PI / teeth; + + glNormal3f(-cos(angle), -sin(angle), 0.0); + glVertex3f(r0 * cos(angle), r0 * sin(angle), -width * 0.5); + glVertex3f(r0 * cos(angle), r0 * sin(angle), width * 0.5); + } + glEnd(); +} + +static GLfloat view_rotx = 20.0, view_roty = 30.0, view_rotz = 0.0; +static GLint gear1, gear2, gear3; +static GLfloat angle = 0.0; + +static void draw(void) { + glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); + + glPushMatrix(); + glRotatef(view_rotx, 1.0, 0.0, 0.0); + glRotatef(view_roty, 0.0, 1.0, 0.0); + glRotatef(view_rotz, 0.0, 0.0, 1.0); + + glPushMatrix(); + glTranslatef(-3.0, -2.0, 0.0); + glRotatef(angle, 0.0, 0.0, 1.0); + glCallList(gear1); + glPopMatrix(); + + glPushMatrix(); + glTranslatef(3.1, -2.0, 0.0); + glRotatef(-2.0 * angle - 9.0, 0.0, 0.0, 1.0); + glCallList(gear2); + glPopMatrix(); + + glPushMatrix(); + glTranslatef(-3.1, 4.2, 0.0); + glRotatef(-2.0 * angle - 25.0, 0.0, 0.0, 1.0); + glCallList(gear3); + glPopMatrix(); + + glPopMatrix(); +} + +/* new window size or exposure */ +static void reshape(int width, int height) { + GLfloat h = (GLfloat)height / (GLfloat)width; + + glViewport(0, 0, (GLint)width, (GLint)height); + glMatrixMode(GL_PROJECTION); + glLoadIdentity(); + glFrustum(-1.0, 1.0, -h, h, 5.0, 60.0); + glMatrixMode(GL_MODELVIEW); + glLoadIdentity(); + glTranslatef(0.0, 0.0, -40.0); +} + +static void init(void) { + static GLfloat pos[4] = + {5.0, 5.0, 10.0, 0.0}; + static GLfloat red[4] = + {0.8, 0.1, 0.0, 1.0}; + static GLfloat green[4] = + {0.0, 0.8, 0.2, 1.0}; + static GLfloat blue[4] = + {0.2, 0.2, 1.0, 1.0}; + + glLightfv(GL_LIGHT0, GL_POSITION, pos); + glEnable(GL_CULL_FACE); + glEnable(GL_LIGHTING); + glEnable(GL_LIGHT0); + glEnable(GL_DEPTH_TEST); + + /* make the gears */ + gear1 = glGenLists(1); + glNewList(gear1, GL_COMPILE); + glMaterialfv(GL_FRONT, GL_AMBIENT_AND_DIFFUSE, red); + gear(1.0, 4.0, 1.0, 20, 0.7); + glEndList(); + + gear2 = glGenLists(1); + glNewList(gear2, GL_COMPILE); + glMaterialfv(GL_FRONT, GL_AMBIENT_AND_DIFFUSE, green); + gear(0.5, 2.0, 2.0, 10, 0.7); + glEndList(); + + gear3 = glGenLists(1); + glNewList(gear3, GL_COMPILE); + glMaterialfv(GL_FRONT, GL_AMBIENT_AND_DIFFUSE, blue); + gear(1.3, 2.0, 0.5, 10, 0.7); + glEndList(); + + glEnable(GL_NORMALIZE); +} + +static void tick(MwWidget handle, void* user, void* client) { + (void)handle; + (void)user; + (void)client; + + draw(); + angle += 2.0; + + MwOpenGLSwapBuffer(opengl); +} + +static void resize(MwWidget handle, void* user, void* client) { + int ww, wh; + + (void)handle; + (void)user; + (void)client; + + ww = MwGetInteger(handle, MwNwidth) - 100; + wh = MwGetInteger(handle, MwNheight) - 100; + + MwVaApply(opengl, + MwNwidth, ww, + MwNheight, wh, + NULL); + + reshape(ww, wh); +} + +int main() { + MwWidget window; + + window = MwVaCreateWidget(MwWindowClass, "main", NULL, 0, 0, 500, 500, + MwNtitle, "main", + NULL); + opengl = MwCreateWidget(MwOpenGLClass, "opengl", window, 50, 50, 400, 400); + + MwOpenGLMakeCurrent(opengl); + + init(); + reshape(400, 400); + + MwAddUserHandler(window, MwNresizeHandler, resize, NULL); + MwAddUserHandler(window, MwNtickHandler, tick, NULL); + + MwLoop(window); +} diff --git a/src/core.c b/src/core.c index fdea2ff..2f05c7b 100644 --- a/src/core.c +++ b/src/core.c @@ -96,7 +96,7 @@ MwWidget MwCreateWidget(MwClass widget_class, const char* name, MwWidget parent, shdefault(h->handler, NULL); shdefault(h->data, NULL); - if(MwDispatch2(h, create)) { + if(MwDispatch2(h, create) != 0) { h->widget_class = NULL; MwDestroyWidget(h); return NULL;