Mercurial > hg > ascension / file revision

 /*

  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.

  * Copyright 2023 Mike Becker. All rights reserved.

  *

  * Redistribution and use in source and binary forms, with or without

  * modification, are permitted provided that the following conditions are met:

  *

  *   1. Redistributions of source code must retain the above copyright

  *      notice, this list of conditions and the following disclaimer.

  *

  *   2. Redistributions in binary form must reproduce the above copyright

  *      notice, this list of conditions and the following disclaimer in the

  *      documentation and/or other materials provided with the distribution.

  *

  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"

  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE

  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR

  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF

  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS

  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN

  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

  * POSSIBILITY OF SUCH DAMAGE.

  */

 #include "ascension/window.h"

 #include "ascension/context.h"

 #include "ascension/error.h"

 #include "ascension/utils.h"

 #include <cx/printf.h>

 #include <GL/glew.h>

 static void asc_gl_debug_callback(

         GLenum source, GLenum type, GLuint id, GLenum severity,

         GLsizei length, const GLchar* message,

         const void* userParam

 ) {

     cxmutstr buf = cx_asprintf(

             "source = %d, id = %u, type = %d, severity= %d, message = %.*s",

             source, id, type, severity, length, message);

     if (type == GL_DEBUG_TYPE_ERROR) {

         asc_error(buf.ptr);

     } else {

         asc_dprintf("GL debug: %.*s", (int)buf.length, buf.ptr);

     }

     cx_strfree(&buf);

 }

 void asc_window_settings_init_defaults(AscWindowSettings* settings) {

     settings->depth_size = 24;

     settings->vsync = 1;

     settings->dimensions.width = 800;

     settings->dimensions.height = 600;

     settings->fullscreen = 0;

     settings->gl_major_version = 4;

     settings->gl_minor_version = 0;

     settings->title = "Ascended Window";

 }

 AscWindow *asc_window_initialize(unsigned int index, AscWindowSettings const *settings) {

     if (index >= ASC_MAX_WINDOWS) {

         asc_error("Maximum number of windows exceeded.");

         return NULL;

     }

     AscWindow *window = &asc_context.windows[index];

     if (window->id > 0) {

         asc_error("Cannot create window - slot already occupied.");

         asc_dprintf("Tried to create window with index %u", index);

         return NULL;

     }

     Uint32 flags = SDL_WINDOW_OPENGL | SDL_WINDOW_SHOWN;

     flags |= settings->fullscreen ? SDL_WINDOW_FULLSCREEN_DESKTOP : SDL_WINDOW_RESIZABLE;

     window->window = SDL_CreateWindow(

             settings->title,

             SDL_WINDOWPOS_CENTERED,

             SDL_WINDOWPOS_CENTERED,

             settings->dimensions.width,

             settings->dimensions.height,

             flags

     );

     if (window->window == NULL) {

         asc_error(SDL_GetError());

         return NULL;

     }

     window->id = SDL_GetWindowID(window->window);

     SDL_GetWindowSize(window->window,

             &window->dimensions.width,

             &window->dimensions.height

     );

     asc_mat4f_ortho(

             window->projection,

             0,

             (float) window->dimensions.width,

             (float) window->dimensions.height,

             0

     );

     SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_CORE);

     SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, settings->gl_major_version);

     SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, settings->gl_minor_version);

     SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, settings->depth_size);

     SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);

     window->glctx = SDL_GL_CreateContext(window->window);

     if (window->glctx == NULL) {

         asc_dprintf("Creating GL context failed for window %u", window->id);

     } else {

         glewExperimental = GL_TRUE;

         GLenum err = glewInit();

         if (err == GLEW_OK) {

             SDL_GL_SetSwapInterval(settings->vsync);

             glEnable(GL_DEPTH_TEST);

             glEnable(GL_BLEND);

             glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

             glEnable(GL_DEBUG_OUTPUT);

             glDebugMessageCallback(asc_gl_debug_callback, NULL);

             asc_dprintf("Window %u initialized", window->id);

             if (asc_primitives_init(&window->primitives)) {

                 asc_context.active_window = window;

                 return window;

             } else {

                 asc_dprintf("!!! Creating primitives for window %u failed !!!", window->id);

             }

         } else {

             asc_error(glewGetErrorString(err));

         }

     }

     // cleanup on error

     if (window->glctx != NULL) {

         SDL_GL_DeleteContext(window->glctx);

     }

     window->glctx = NULL;

     SDL_DestroyWindow(window->window);

     window->window = NULL;

     window->id = 0;

 }

 void asc_window_destroy(AscWindow* window) {

     // safeguard

     if (window->id == 0) return;

     // this window cannot be active anymore

     if (asc_context.active_window == window) {

         asc_context.active_window = NULL;

     }

     // release context related data (we have to make the GL context current for this)

     SDL_GL_MakeCurrent(window->window, window->glctx);

     asc_primitives_destroy(&window->primitives);

     // destroy the GL context and the window

     if (window->glctx != NULL) {

         SDL_GL_DeleteContext(window->glctx);

     }

     if (window->window != NULL) {

         SDL_DestroyWindow(window->window);

     }

     // if another window was active, make the other context current again

     if (asc_context.active_window != NULL) {

         AscWindow const *aw = asc_context.active_window;

         SDL_GL_MakeCurrent(aw->window, aw->glctx);

     }

     // clean the data

     asc_dprintf("Window %u and its OpenGL context destroyed.", window->id);

     memset(window, 0, sizeof(AscWindow));

 }

 void asc_window_sync(AscWindow const* window) {

     AscWindow const *active_window = asc_context.active_window;

     if (window != active_window) {

         asc_window_activate(window);

     }

     SDL_GL_SwapWindow(window->window);

     glViewport(0, 0, window->dimensions.width, window->dimensions.height);

     glClearColor(0.0f, 0.0f, 0.0f, 1.0f);

     glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

     if (window != active_window) {

         asc_window_activate(active_window);

     }

 }

 void asc_window_activate(AscWindow const *window) {

     SDL_GL_MakeCurrent(window->window, window->glctx);

     asc_context.active_window = window;

 }