ascension: src/text.c@e26b4ac1661c

invert the logic of converting between specialized nodes and the generic interface

     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     // TODO: when we group draw calls, we don't need to activate shader here

    41     glUseProgram(ASC_SHADER_FONT.base.id);

    43     // TODO: when we group UI draw calls, we don't need to upload matrices here

    44     // Upload matrices

    45     glUniformMatrix4fv(ASC_SHADER_FONT.base.projection, 1,

    46                        GL_FALSE, asc_context.active_window->projection);

    47     glUniformMatrix4fv(ASC_SHADER_FONT.base.model, 1,

    48                        GL_FALSE, node->base.transform);

    50     // Upload surface

    51     glActiveTexture(GL_TEXTURE0);

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

    53     glUniform1i(ASC_SHADER_FONT.surface, 0);

    55     // Draw mesh

    56     asc_primitives_draw_plane();

    57 }

    59 static void asc_text_update(AscText *node) {

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

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

    62         return;

    63     }

    65     // Generate new texture, if required

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

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

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

    69         glTexParameteri(GL_TEXTURE_RECTANGLE, GL_TEXTURE_MIN_FILTER, GL_LINEAR);

    70         glTexParameteri(GL_TEXTURE_RECTANGLE, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

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

    72     }

    74     // Render text onto a surface

    75     SDL_Surface *surface = TTF_RenderUTF8_Blended_Wrapped(

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

    77             node->text,

    78             asc_col_sdl(node->color),

    79             node->max_width

    80     );

    81     if (surface == NULL) {

    82         asc_error(SDL_GetError());

    83         return;

    84     }

    86     // Transform

    87     asc_transform_scale(node->base.transform, (float) surface->w, (float) surface->h, 0);

    88     asc_transform_translate2i(node->base.transform, node->position);

    90     // Transfer Image Data

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

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

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

    94     glTexImage2D(GL_TEXTURE_RECTANGLE, 0, GL_RGBA,

    95                  surface->w, surface->h,

    96                  0, GL_BGRA, GL_UNSIGNED_BYTE, surface->pixels);

    98     // Free the surface

    99     SDL_FreeSurface(surface);

   100 }

   102 AscSceneNode *asc_text(int x, int y, char const *text) {

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

   104     if (node == NULL) {

   105         asc_error("Out of memory.");

   106         return NULL;

   107     }

   109     node->base.free_func = (asc_scene_free_func) asc_text_free;

   110     node->base.update_func = (asc_scene_update_func) asc_text_update;

   111     node->base.draw_func = (asc_scene_draw_func) asc_text_draw;

   113     node->position.x = x;

   114     node->position.y = y;

   115     node->font = asc_context.active_font;

   116     node->color = asc_context.ink;

   117     if (text != NULL) {

   118         node->text = strdup(text);

   119     }

   121     return &node->base;

   122 }

   124 void asc_text_free(AscText *node) {

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

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

   127     free(node->text);

   128     free(node);

   129 }

Mercurial > hg > ascension / file revision