From 3b2fceed064c06d55e1cd33d51e855e909c81f75 Mon Sep 17 00:00:00 2001 From: dec05eba Date: Sun, 10 Oct 2021 12:56:55 +0200 Subject: add event and test graphics --- README.md | 6 +++- include/mgl/gl.h | 14 ++++++++ include/mgl/glx.h | 10 ++++-- include/mgl/mgl.h | 4 +++ include/mgl/window.h | 17 ++++++++-- project.conf | 3 ++ src/gl.c | 53 +++++++++++++++++++++++++++++ src/glx.c | 26 ++++++++++++--- src/mgl.c | 86 +++++++++++++++++++++++++++++++++++++++++++++-- src/window.c | 94 +++++++++++++++++++++++++++++++++++++++++++++++++++- tests/main.c | 31 ++++++++++++++++- tests/project.conf | 3 ++ 12 files changed, 331 insertions(+), 16 deletions(-) create mode 100644 include/mgl/gl.h create mode 100644 src/gl.c create mode 100644 tests/project.conf diff --git a/README.md b/README.md index b96efe3..80de338 100644 --- a/README.md +++ b/README.md @@ -1,7 +1,11 @@ # Minimal Graphics Library +Written in C. # Dependencies ## Build `xlib` ## Runtime -`libglvnd (libGLX.so, libOpenGL.so)` \ No newline at end of file +`libglvnd (libGLX.so, libOpenGL.so)` + +# TODO +vsync \ No newline at end of file diff --git a/include/mgl/gl.h b/include/mgl/gl.h new file mode 100644 index 0000000..1791059 --- /dev/null +++ b/include/mgl/gl.h @@ -0,0 +1,14 @@ +#ifndef MGL_GL_H +#define MGL_GL_H + +typedef struct { + void *handle; + void (*glViewport)(int x, int y, int width, int height); + void (*glClearColor)(float red, float green, float blue, float alpha); + void (*glClear)(unsigned int mask); +} mgl_gl; + +int mgl_gl_load(mgl_gl *self); +void mgl_gl_unload(mgl_gl *self); + +#endif /* MGL_GL_H */ diff --git a/include/mgl/glx.h b/include/mgl/glx.h index dfb736d..4197402 100644 --- a/include/mgl/glx.h +++ b/include/mgl/glx.h @@ -1,12 +1,18 @@ #ifndef MGL_GLX_H #define MGL_GLX_H +typedef struct _XVisualInfo _XVisualInfo; typedef struct _XDisplay Display; -typedef struct __GLXFBConfigRec *GLXFBConfig; +typedef struct __GLXcontextRec *GLXContext; +typedef unsigned long GLXDrawable; typedef struct { void *handle; - GLXFBConfig* (*glXGetFBConfigs)(Display *dpy, int screen, int *nelements); + _XVisualInfo* (*glXChooseVisual)(Display *dpy, int screen, int *attribList); + GLXContext (*glXCreateContext)(Display *dpy, _XVisualInfo *vis, GLXContext shareList, int direct); + void (*glXDestroyContext)(Display *dpy, GLXContext ctx); + int (*glXMakeCurrent)(Display *dpy, GLXDrawable drawable, GLXContext ctx); + void (*glXSwapBuffers)(Display *dpy, GLXDrawable drawable); } mgl_glx; int mgl_glx_load(mgl_glx *self); diff --git a/include/mgl/mgl.h b/include/mgl/mgl.h index d896497..606c14b 100644 --- a/include/mgl/mgl.h +++ b/include/mgl/mgl.h @@ -2,13 +2,17 @@ #define MGL_MGL_H #include "glx.h" +#include "gl.h" /* Display* on x11 */ typedef void* mgl_connection; typedef struct { mgl_connection connection; + GLXContext glx_context; + _XVisualInfo *visual_info; mgl_glx glx; + mgl_gl gl; } mgl_context; /* diff --git a/include/mgl/window.h b/include/mgl/window.h index bd29936..c6dc9e2 100644 --- a/include/mgl/window.h +++ b/include/mgl/window.h @@ -1,12 +1,23 @@ #ifndef MGL_WINDOW_H #define MGL_WINDOW_H +typedef struct mgl_window mgl_window; + typedef struct { - int booba; -} mgl_window; + void (*draw)(mgl_window *window, void *userdata); +} mgl_window_callback; + +struct mgl_window { + unsigned long window; + mgl_window_callback callback; + void *callback_userdata; +}; -void mgl_window_init(mgl_window *self); +int mgl_window_create(mgl_window *self, const char *title, int width, int height, mgl_window_callback *callback, void *userdata); +int mgl_window_create_with_params(mgl_window *self, const char *title, int width, int height, unsigned long parent_window, mgl_window_callback *callback, void *userdata); void mgl_window_deinit(mgl_window *self); + void mgl_window_show(mgl_window *self); +void mgl_window_event_poll(mgl_window *self, int timeout_ms); #endif /* MGL_WINDOW_H */ diff --git a/project.conf b/project.conf index f9d0fdc..62353a2 100644 --- a/project.conf +++ b/project.conf @@ -4,5 +4,8 @@ type = "static" version = "0.1.0" platforms = ["posix"] +[config] +expose_include_dirs = ["include"] + [dependencies] x11 = ">=1" \ No newline at end of file diff --git a/src/gl.c b/src/gl.c new file mode 100644 index 0000000..c83ab49 --- /dev/null +++ b/src/gl.c @@ -0,0 +1,53 @@ +#include "../include/mgl/gl.h" +#include +/*#include */ +#include + +typedef struct { + void **func; + const char *name; +} dlsym_assign; + +static void* dlsym_print_fail(void *handle, const char *name) { + dlerror(); + void *sym = dlsym(handle, name); + char *err_str = dlerror(); + + if(!sym) + fprintf(stderr, "dlsym(handle, \"%s\") failed, error: %s\n", name, err_str ? err_str : "(null)"); + + return sym; +} + +int mgl_gl_load(mgl_gl *self) { + const char *gl_path = "/usr/lib/libOpenGL.so.0"; + self->handle = dlopen(gl_path, RTLD_LAZY); + if(!self->handle) { + fprintf(stderr, "dlopen(\"%s\", RTLD_LAZY) failed\n", gl_path); + return -1; + } + + const dlsym_assign assign[] = { + { &self->glViewport, "glViewport" }, + { &self->glClearColor, "glClearColor" }, + { &self->glClear, "glClear" }, + { NULL, NULL } + }; + + for(int i = 0; assign[i].func; ++i) { + *assign[i].func = dlsym_print_fail(self->handle, assign[i].name); + if(!assign[i].func) { + mgl_gl_unload(self); + return -1; + } + } + + return 0; +} + +void mgl_gl_unload(mgl_gl *self) { + if(self->handle) { + dlclose(self->handle); + self->handle = NULL; + } +} diff --git a/src/glx.c b/src/glx.c index 4a5af9d..6712947 100644 --- a/src/glx.c +++ b/src/glx.c @@ -1,7 +1,12 @@ #include "../include/mgl/glx.h" #include +/*#include */ #include -#include + +typedef struct { + void **func; + const char *name; +} dlsym_assign; static void* dlsym_print_fail(void *handle, const char *name) { dlerror(); @@ -22,10 +27,21 @@ int mgl_glx_load(mgl_glx *self) { return -1; } - self->glXGetFBConfigs = (GLXFBConfig* (*)(Display*, int, int*))dlsym_print_fail(self->handle, "glXGetFBConfigs"); - if(!self->glXGetFBConfigs) { - mgl_glx_unload(self); - return -1; + const dlsym_assign assign[] = { + { &self->glXChooseVisual, "glXChooseVisual" }, + { &self->glXCreateContext, "glXCreateContext" }, + { &self->glXDestroyContext, "glXDestroyContext" }, + { &self->glXMakeCurrent, "glXMakeCurrent" }, + { &self->glXSwapBuffers, "glXSwapBuffers" }, + { NULL, NULL } + }; + + for(int i = 0; assign[i].func; ++i) { + *assign[i].func = dlsym_print_fail(self->handle, assign[i].name); + if(!assign[i].func) { + mgl_glx_unload(self); + return -1; + } } return 0; diff --git a/src/mgl.c b/src/mgl.c index a7221d0..27d33ae 100644 --- a/src/mgl.c +++ b/src/mgl.c @@ -1,7 +1,26 @@ #include "../include/mgl/mgl.h" -#include +#include +#include #include +#define GLX_USE_GL 1 +#define GLX_BUFFER_SIZE 2 +#define GLX_LEVEL 3 +#define GLX_RGBA 4 +#define GLX_DOUBLEBUFFER 5 +#define GLX_STEREO 6 +#define GLX_AUX_BUFFERS 7 +#define GLX_RED_SIZE 8 +#define GLX_GREEN_SIZE 9 +#define GLX_BLUE_SIZE 10 +#define GLX_ALPHA_SIZE 11 +#define GLX_DEPTH_SIZE 12 +#define GLX_STENCIL_SIZE 13 +#define GLX_ACCUM_RED_SIZE 14 +#define GLX_ACCUM_GREEN_SIZE 15 +#define GLX_ACCUM_BLUE_SIZE 16 +#define GLX_ACCUM_ALPHA_SIZE 17 + static mgl_context context; static int init_count = 0; static XErrorHandler prev_xerror = NULL; @@ -12,6 +31,46 @@ static int ignore_xerror(Display *display, XErrorEvent *ee) { return 0; } +static int glx_context_init() { + const int attr[] = { + GLX_RGBA, + GLX_DEPTH_SIZE, 0, + GLX_STENCIL_SIZE, 0, + GLX_RED_SIZE, 8, + GLX_GREEN_SIZE, 8, + GLX_BLUE_SIZE, 8, + GLX_ALPHA_SIZE, 0, + GLX_DOUBLEBUFFER, /* TODO: Add option to turn this off? */ + None + }; + + context.visual_info = context.glx.glXChooseVisual(context.connection, DefaultScreen(context.connection), (int*)attr); + if(!context.visual_info) { + fprintf(stderr, "glXChooseVisual failed, no appropriate visual found\n"); + return -1; + } + + context.glx_context = context.glx.glXCreateContext(context.connection, context.visual_info, NULL, 1); + if(!context.glx_context) { + fprintf(stderr, "glXCreateContext failed\n"); + return -1; + } + + return 0; +} + +static void glx_context_deinit() { + if(context.glx_context) { + context.glx.glXDestroyContext(context.connection, context.glx_context); + context.glx_context = NULL; + } + + if(context.visual_info) { + XFree(context.visual_info); + context.visual_info = NULL; + } +} + int mgl_init(void) { ++init_count; if(init_count == 1) { @@ -23,20 +82,35 @@ int mgl_init(void) { } prev_xerror = XSetErrorHandler(ignore_xerror); + if(mgl_glx_load(&context.glx) != 0) { mgl_deinit(); return -1; } + + if(mgl_gl_load(&context.gl) != 0) { + mgl_deinit(); + return -1; + } + + if(glx_context_init() != 0) { + mgl_deinit(); + return -1; + } } return 0; } void mgl_deinit(void) { if(init_count == 1) { + glx_context_deinit(); + mgl_gl_unload(&context.gl); mgl_glx_unload(&context.glx); XSetErrorHandler(prev_xerror); - XCloseDisplay(context.connection); - context.connection = NULL; + if(context.connection) { + XCloseDisplay(context.connection); + context.connection = NULL; + } } if(init_count > 0) @@ -44,5 +118,11 @@ void mgl_deinit(void) { } mgl_context* mgl_get_context(void) { +#ifndef NDEBUG + if(init_count == 0) { + fprintf(stderr, "Error: mgl_get_context was called before mgl_init\n"); + abort(); + } +#endif return &context; } diff --git a/src/window.c b/src/window.c index 39855da..9836907 100644 --- a/src/window.c +++ b/src/window.c @@ -1,13 +1,105 @@ #include "../include/mgl/window.h" +#include "../include/mgl/mgl.h" +#include +#include -void mgl_window_init(mgl_window *self) { +#define GL_COLOR_BUFFER_BIT 0x00004000 +int mgl_window_create(mgl_window *self, const char *title, int width, int height, mgl_window_callback *callback, void *userdata) { + return mgl_window_create_with_params(self, title, width, height, DefaultRootWindow(mgl_get_context()->connection), callback, userdata); +} + +int mgl_window_create_with_params(mgl_window *self, const char *title, int width, int height, unsigned long parent_window, mgl_window_callback *callback, void *userdata) { + self->window = 0; + self->callback = *callback; + self->callback_userdata = userdata; + + mgl_context *context = mgl_get_context(); + + Colormap color_map = XCreateColormap(context->connection, DefaultRootWindow(context->connection), ((XVisualInfo*)context->visual_info)->visual, AllocNone); + if(!color_map) { + fprintf(stderr, "XCreateColormap failed\n"); + return -1; + } + + XSetWindowAttributes window_attr; + window_attr.colormap = color_map; + window_attr.event_mask = ExposureMask | KeyPressMask; + + self->window = XCreateWindow(context->connection, parent_window, 0, 0, width, height, 0, ((XVisualInfo*)context->visual_info)->depth, InputOutput, ((XVisualInfo*)context->visual_info)->visual, CWColormap | CWEventMask, &window_attr); + //XFreeColormap(context->connection, color_map); + if(!self->window) { + fprintf(stderr, "XCreateWindow failed\n"); + mgl_window_deinit(self); + return -1; + } + + /* TODO: Test utf8 */ + XStoreName(context->connection, self->window, title); + return 0; } void mgl_window_deinit(mgl_window *self) { + mgl_context *context = mgl_get_context(); + if(self->window) { + XDestroyWindow(context->connection, self->window); + self->window = 0; + } +} + +static void mgl_window_draw(mgl_window *self) { + mgl_context *context = mgl_get_context(); + + /* TODO: Get window size from window resize event instead */ + XWindowAttributes gwa; + XGetWindowAttributes(context->connection, self->window, &gwa); + + context->gl.glViewport(0, 0, gwa.width, gwa.height); + context->gl.glClear(GL_COLOR_BUFFER_BIT); + context->gl.glClearColor(0.0f, 0.0f, 0.0f, 1.0f); + if(self->callback.draw) + self->callback.draw(self, self->callback_userdata); + context->glx.glXSwapBuffers(context->connection, self->window); } void mgl_window_show(mgl_window *self) { + mgl_context *context = mgl_get_context(); + + XMapWindow(context->connection, self->window); + XFlush(context->connection); + + /* TODO: Switch current when rendering to another window, and set current to NULL when destroying the currently selected context */ + context->glx.glXMakeCurrent(context->connection, self->window, context->glx_context); + mgl_window_draw(self); +} + +static void on_receive_x11_event(mgl_window *window, XEvent *xev) { + switch(xev->type) { + case Expose: + mgl_window_draw(window); + break; + } +} + +void mgl_window_event_poll(mgl_window *self, int timeout_ms) { + Display *display = mgl_get_context()->connection; + const int x11_fd = ConnectionNumber(display); + + fd_set in_fds; + FD_ZERO(&in_fds); /* TODO: Optimize */ + FD_SET(x11_fd, &in_fds); + + struct timeval tv; + tv.tv_sec = timeout_ms / 1000; + tv.tv_usec = (timeout_ms * 1000) - (tv.tv_sec * 1000 * 1000); + const int num_ready_fds = select(1 + x11_fd, &in_fds, NULL, NULL, &tv); + if(num_ready_fds > 0) { + XEvent xev; + while(XPending(display)) { + XNextEvent(display, &xev); + on_receive_x11_event(self, &xev); + } + } } diff --git a/tests/main.c b/tests/main.c index ff1570b..e6a4f5a 100644 --- a/tests/main.c +++ b/tests/main.c @@ -1,6 +1,35 @@ #include +#include +#include +#include +#include + +static void draw(mgl_window *window, void *userdata) { + glBegin(GL_QUADS); + glColor3f(1., 0., 0.); glVertex3f(-.75, -.75, 0.); + glColor3f(0., 1., 0.); glVertex3f( .75, -.75, 0.); + glColor3f(0., 0., 1.); glVertex3f( .75, .75, 0.); + glColor3f(1., 1., 0.); glVertex3f(-.75, .75, 0.); + glEnd(); +} int main(int argc, char **argv) { - printf("hello, world!\n"); + if(mgl_init() != 0) + return 1; + + mgl_window_callback window_callback; + window_callback.draw = draw; + + mgl_window window; + if(mgl_window_create(&window, "mgl", 1280, 720, &window_callback, NULL) != 0) + return 1; + + mgl_window_show(&window); + for(;;) { + mgl_window_event_poll(&window, 500); + } + + mgl_window_deinit(&window); + mgl_deinit(); return 0; } diff --git a/tests/project.conf b/tests/project.conf new file mode 100644 index 0000000..3c15235 --- /dev/null +++ b/tests/project.conf @@ -0,0 +1,3 @@ +[dependencies] +gl = ">=1" +glu = ">=9" -- cgit v1.2.3