ascension: src/text.c@c5dde81b6fb2 (annotated)

src/text.c@c5dde81b6fb2 (annotated)

src/text.c

Wed, 15 Nov 2023 22:51:40 +0100

author: Mike Becker <universe@uap-core.de>
date: Wed, 15 Nov 2023 22:51:40 +0100
changeset 16: c5dde81b6fb2
parent 14: src/ascension/font.h@9dbfc0031887
child 17: 25013a35e07d
permissions: -rw-r--r--

add text rendering and demo FPS counter

 /*
  * 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/text.h"
 #include "ascension/context.h"
 #include "ascension/error.h"
 #include "ascension/shader.h"
 #include <GL/glew.h>
 void asc_text_draw_lb(
         AscTextNode *node,
         asc_vec2i position,
         unsigned max_width,
         cxmutstr text) {
     // Generate new texture, if required
     if (node->tex_id == 0) {
         glGenTextures(1, &node->tex_id);
         glBindTexture(GL_TEXTURE_RECTANGLE, node->tex_id);
         glTexParameteri(GL_TEXTURE_RECTANGLE, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
         glTexParameteri(GL_TEXTURE_RECTANGLE, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
         asc_dprintf("Generated new texture for text node: %u", node->tex_id);
     }
     // Render text onto a surface
     SDL_Surface *surface = TTF_RenderText_Blended_Wrapped(
             asc_context.active_font->ptr,
             text.ptr,
             (SDL_Color) {
                     .r = asc_context.ink.red,
                     .g = asc_context.ink.green,
                     .b = asc_context.ink.blue,
                     .a = asc_context.ink.alpha
             },
             max_width
     );
     if (surface == NULL) {
         asc_error(SDL_GetError());
         return;
     }
     // Store basic node information
     node->position = position;
     node->dimension.width = surface->w;
     node->dimension.height = surface->h;
     // Transfer Image Data
     // TODO: move the image data transfer to a separate function - we will need it more often
     glBindTexture(GL_TEXTURE_RECTANGLE, node->tex_id);
     glPixelStorei(GL_UNPACK_ROW_LENGTH, surface->pitch / surface->format->BytesPerPixel);
     glTexImage2D(GL_TEXTURE_RECTANGLE, 0, GL_RGBA,
                  surface->w, surface->h,
 , GL_BGRA, GL_UNSIGNED_BYTE, surface->pixels);
     // Free the surface
     SDL_FreeSurface(surface);
     // Redraw the node
     asc_text_redraw(node);
 }
 void asc_text_draw(
         AscTextNode *node,
         asc_vec2i position,
         cxmutstr text) {
     unsigned max_width = asc_context.active_window->dimensions.width - position.width;
     asc_text_draw_lb(node, position, max_width, text);
 }
 void asc_text_redraw(AscTextNode *node) {
     if (node->tex_id == 0) {
         asc_error("Tried to redraw text node after destruction");
         return;
     }
     glUseProgram(ASC_SHADER_FONT.base.id);
     // Upload projection
     // TODO: when we group UI draw calls, we don't need this
     glUniformMatrix4fv(ASC_SHADER_FONT.base.projection, 1, GL_FALSE, asc_context.active_window->projection);
     // Upload model matrix
     asc_mat4f model = {0};
     model[asc_mat4_index(0, 0)] = node->dimension.width;
     model[asc_mat4_index(1, 1)] = node->dimension.height;
     model[asc_mat4_index(3, 0)] = node->position.x;
     model[asc_mat4_index(3, 1)] = node->position.y;
     model[asc_mat4_index(3, 3)] = 1;
     glUniformMatrix4fv(ASC_SHADER_FONT.base.model, 1, GL_FALSE, model);
     // Upload surface
     glActiveTexture(GL_TEXTURE0);
     glBindTexture(GL_TEXTURE_RECTANGLE, node->tex_id);
     glUniform1i(ASC_SHADER_FONT.surface, 0);
     // Draw mesh
     asc_primitives_draw_plane();
 }
 void asc_text_destroy(AscTextNode *node) {
     asc_dprintf("Release text node texture: %u", node->tex_id);
     glDeleteTextures(1, &node->tex_id);
     node->tex_id = 0;
 }

Mercurial > hg > ascension / annotate

src/text.c@c5dde81b6fb2 (annotated)

src/text.c