ascension: src/text.c@8324037e0148

     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 static void asc_text_draw(AscText const *node) {

    36     if (node->color.alpha == 0 || node->hidden || node->internal.tex_id == 0) {

    37         return;

    38     }

    40     glUseProgram(ASC_SHADER_FONT.base.id);

    42     // Upload projection

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

    44     glUniformMatrix4fv(ASC_SHADER_FONT.base.projection, 1,

    45                        GL_FALSE, asc_context.active_window->projection);

    47     // Upload model matrix

    48     asc_mat4f model = {0};

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

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

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

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

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

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

    56     // Upload surface

    57     glActiveTexture(GL_TEXTURE0);

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

    59     glUniform1i(ASC_SHADER_FONT.surface, 0);

    61     // Draw mesh

    62     asc_primitives_draw_plane();

    63 }

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

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

    67     if (node == NULL) {

    68         asc_error("Out of memory.");

    69         return NULL;

    70     }

    72     node->node.free_func = (asc_scene_free_func) asc_text_free;

    73     node->node.draw_func = (asc_scene_draw_func) asc_text_draw;

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

    76     node->font = asc_context.active_font;

    77     node->color = asc_context.ink;

    78     if (text != NULL) {

    79         node->text = strdup(text);

    80     }

    82     return node;

    83 }

    85 void asc_text_update(AscText *node) {

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

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

    88         return;

    89     }

    91     // Generate new texture, if required

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

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

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

    95         glTexParameteri(GL_TEXTURE_RECTANGLE, GL_TEXTURE_MIN_FILTER, GL_LINEAR);

    96         glTexParameteri(GL_TEXTURE_RECTANGLE, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

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

    98     }

   100     // Render text onto a surface

   101     SDL_Surface *surface = TTF_RenderUTF8_Blended_Wrapped(

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

   103             node->text,

   104             asc_col_sdl(node->color),

   105             node->max_width

   106     );

   107     if (surface == NULL) {

   108         asc_error(SDL_GetError());

   109         return;

   110     }

   112     // Store basic node information

   113     node->position = node->position;

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

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

   117     // Transfer Image Data

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

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

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

   121     glTexImage2D(GL_TEXTURE_RECTANGLE, 0, GL_RGBA,

   122                  surface->w, surface->h,

   123                  0, GL_BGRA, GL_UNSIGNED_BYTE, surface->pixels);

   125     // Free the surface

   126     SDL_FreeSurface(surface);

   127 }

   129 void asc_text_free(AscText *node) {

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

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

   132     free(node->text);

   133     free(node);

   134 }

Mercurial > hg > ascension / file revision