ascension: src/text.c@8acde7d27904

     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/text.h"

    29 #include "ascension/context.h"

    30 #include "ascension/error.h"

    31 #include "ascension/shader.h"

    33 #include <GL/glew.h>

    35 AscText *asc_text(int x, int y, char const *text) {

    36     AscText *node = calloc(1, sizeof(AscText));

    37     if (node == NULL) {

    38         asc_error("Out of memory.");

    39         return NULL;

    40     }

    42     node->position = (asc_vec2i) {x, y};

    43     node->font = asc_context.active_font;

    44     node->color = asc_context.ink;

    45     if (text != NULL) {

    46         node->text = strdup(text);

    47     }

    49     return node;

    50 }

    52 void asc_text_update(AscText *node) {

    53     // short circuit if fully transparent or hidden, we don't need anything

    54     if (node->color.alpha == 0 || node->hidden) {

    55         return;

    56     }

    58     // Generate new texture, if required

    59     if (node->internal.tex_id == 0) {

    60         glGenTextures(1, &node->internal.tex_id);

    61         glBindTexture(GL_TEXTURE_RECTANGLE, node->internal.tex_id);

    62         glTexParameteri(GL_TEXTURE_RECTANGLE, GL_TEXTURE_MIN_FILTER, GL_LINEAR);

    63         glTexParameteri(GL_TEXTURE_RECTANGLE, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

    64         asc_dprintf("Generated new texture for text node: %u", node->internal.tex_id);

    65     }

    67     // Render text onto a surface

    68     SDL_Surface *surface = TTF_RenderUTF8_Blended_Wrapped(

    69             asc_font_cache_validate(node->font)->ptr,

    70             node->text,

    71             asc_col_sdl(node->color),

    72             node->max_width

    73     );

    74     if (surface == NULL) {

    75         asc_error(SDL_GetError());

    76         return;

    77     }

    79     // Store basic node information

    80     node->position = node->position;

    81     node->internal.dimension.width = surface->w;

    82     node->internal.dimension.height = surface->h;

    84     // Transfer Image Data

    85     // TODO: move the image data transfer to a separate function - we will need it more often

    86     glBindTexture(GL_TEXTURE_RECTANGLE, node->internal.tex_id);

    87     glPixelStorei(GL_UNPACK_ROW_LENGTH, surface->pitch / surface->format->BytesPerPixel);

    88     glTexImage2D(GL_TEXTURE_RECTANGLE, 0, GL_RGBA,

    89                  surface->w, surface->h,

    90                  0, GL_BGRA, GL_UNSIGNED_BYTE, surface->pixels);

    92     // Free the surface

    93     SDL_FreeSurface(surface);

    94 }

    96 void asc_text_draw(AscText const *node) {

    97     if (node->color.alpha == 0 || node->hidden) {

    98         return;

    99     }

   101     if (node->internal.tex_id == 0) {

   102         asc_error("Tried to redraw text node after destruction");

   103         return;

   104     }

   106     glUseProgram(ASC_SHADER_FONT.base.id);

   108     // Upload projection

   109     // TODO: when we group UI draw calls, we don't need this

   110     glUniformMatrix4fv(ASC_SHADER_FONT.base.projection, 1,

   111                        GL_FALSE, asc_context.active_window->projection);

   113     // Upload model matrix

   114     asc_mat4f model = {0};

   115     model[asc_mat4_index(0, 0)] = node->internal.dimension.width;

   116     model[asc_mat4_index(1, 1)] = node->internal.dimension.height;

   117     model[asc_mat4_index(3, 0)] = node->position.x;

   118     model[asc_mat4_index(3, 1)] = node->position.y;

   119     model[asc_mat4_index(3, 3)] = 1;

   120     glUniformMatrix4fv(ASC_SHADER_FONT.base.model, 1, GL_FALSE, model);

   122     // Upload surface

   123     glActiveTexture(GL_TEXTURE0);

   124     glBindTexture(GL_TEXTURE_RECTANGLE, node->internal.tex_id);

   125     glUniform1i(ASC_SHADER_FONT.surface, 0);

   127     // Draw mesh

   128     asc_primitives_draw_plane();

   129 }

   131 void asc_text_free(AscText *node) {

   132     asc_dprintf("Release text node texture: %u", node->internal.tex_id);

   133     glDeleteTextures(1, &node->internal.tex_id);

   134     free(node->text);

   135     free(node);

   136 }

Mercurial > hg > ascension / file revision