ascension: src/primitives.c@c5dde81b6fb2

     1 /*

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

     3  * Copyright 2023 Mike Becker. All rights reserved.

     4  *

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

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

     7  *

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

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

    10  *

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

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

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

    14  *

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

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

    17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

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

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

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

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

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

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

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

    25  * POSSIBILITY OF SUCH DAMAGE.

    26  */

    28 #include "ascension/primitives.h"

    29 #include "ascension/error.h"

    30 #include "ascension/context.h"

    32 #include <string.h>

    33 #include <GL/glew.h>

    35 static void asc_primitives_init_plane(AscMesh *mesh) {

    36     asc_dprintf("Create primitive plane in VBO %u and VAO %u", mesh->vbo, mesh->vao);

    37     mesh->vertices = 4;

    38     float data[8] = {

    39             0.0f, 0.0f, // bottom left

    40             0.0f, 1.0f,    // top left

    41             1.0f, 0.0f, // bottom right

    42             1.0f, 1.0f    // top right

    43     };

    44     glBindBuffer(GL_ARRAY_BUFFER, mesh->vbo);

    45     glBufferData(GL_ARRAY_BUFFER, sizeof(data), data, GL_STATIC_DRAW);

    46     glBindVertexArray(mesh->vao);

    47     glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 0, NULL);

    48     glEnableVertexAttribArray(0);

    49 }

    51 bool asc_primitives_init(AscPrimitives *primitives) {

    52     asc_dprintf("Create primitives for the GL context of active window.");

    53     // TODO: more primitives

    55     GLuint buffers[1];

    56     GLuint arrays[1];

    57     glGenBuffers(1, buffers);

    58     glGenVertexArrays(1, arrays);

    60     AscMesh *plane = &(primitives->plane);

    61     plane->vbo = buffers[0];

    62     plane->vao = arrays[0];

    63     asc_primitives_init_plane(plane);

    65     GLenum error = glGetError();

    66     if (error == GL_NO_ERROR) {

    67         return true;

    68     } else {

    69         asc_error_gl(error, CX_STR("Initialization of primitive meshes failed."));

    70         return false;

    71     }

    72 }

    74 void asc_primitives_destroy(AscPrimitives *primitives) {

    75     asc_dprintf("Destroy primitives in GL context of active window.");

    77     GLuint buffers[1];

    78     GLuint arrays[1];

    80     buffers[0] = primitives->plane.vbo;

    81     arrays[0] = primitives->plane.vao;

    83     glDeleteBuffers(1, buffers);

    84     glDeleteVertexArrays(1, arrays);

    86     memset(primitives, 0, sizeof(AscPrimitives));

    87 }

    89 void asc_primitives_draw_plane(void) {

    90     AscMesh const *mesh = &(asc_context.active_window->primitives.plane);

    91     glBindVertexArray(mesh->vao);

    92     glDrawArrays(GL_TRIANGLE_STRIP, 0, mesh->vertices);

    93 }

Mercurial > hg > ascension / file revision