feat(rendering): ttf font rendering

assets/font/AUTHORS

@@ -0,0 +1,16 @@
+AUTHORS
+
+Current Contributors (sorted alphabetically):
+  
+  - Vishal Vijayraghavan  <vishalvvr at fedoraproject dot org>
+      Project Owner/ Maintainer (Current)
+      Red Hat, Inc.
+
+Previous Contributors
+  - Pravin Satpute  <psatpute at redhat dot com>
+      Project Owner/ Maintainer 
+      Red Hat, Inc.
+      
+  - Steve Matteson
+      Original Designer
+      Ascender, Inc.

assets/font/LICENSE

@@ -0,0 +1,102 @@
+Digitized data copyright (c) 2010 Google Corporation
+	with Reserved Font Arimo, Tinos and Cousine.
+Copyright (c) 2012 Red Hat, Inc.
+	with Reserved Font Name Liberation.
+
+This Font Software is licensed under the SIL Open Font License,
+Version 1.1.
+
+This license is copied below, and is also available with a FAQ at:
+http://scripts.sil.org/OFL
+
+SIL OPEN FONT LICENSE Version 1.1 - 26 February 2007
+
+PREAMBLE The goals of the Open Font License (OFL) are to stimulate
+worldwide development of collaborative font projects, to support the font
+creation efforts of academic and linguistic communities, and to provide
+a free and open framework in which fonts may be shared and improved in
+partnership with others.
+
+The OFL allows the licensed fonts to be used, studied, modified and
+redistributed freely as long as they are not sold by themselves.
+The fonts, including any derivative works, can be bundled, embedded,
+redistributed and/or sold with any software provided that any reserved
+names are not used by derivative works.  The fonts and derivatives,
+however, cannot be released under any other type of license.  The
+requirement for fonts to remain under this license does not apply to
+any document created using the fonts or their derivatives.
+
+ 
+
+DEFINITIONS
+"Font Software" refers to the set of files released by the Copyright
+Holder(s) under this license and clearly marked as such.
+This may include source files, build scripts and documentation.
+
+"Reserved Font Name" refers to any names specified as such after the
+copyright statement(s).
+
+"Original Version" refers to the collection of Font Software components
+as distributed by the Copyright Holder(s).
+
+"Modified Version" refers to any derivative made by adding to, deleting,
+or substituting ? in part or in whole ?
+any of the components of the Original Version, by changing formats or
+by porting the Font Software to a new environment.
+
+"Author" refers to any designer, engineer, programmer, technical writer
+or other person who contributed to the Font Software.
+
+
+PERMISSION & CONDITIONS
+
+Permission is hereby granted, free of charge, to any person obtaining a
+copy of the Font Software, to use, study, copy, merge, embed, modify,
+redistribute, and sell modified and unmodified copies of the Font
+Software, subject to the following conditions:
+
+1) Neither the Font Software nor any of its individual components,in
+   Original or Modified Versions, may be sold by itself.
+
+2) Original or Modified Versions of the Font Software may be bundled,
+   redistributed and/or sold with any software, provided that each copy
+   contains the above copyright notice and this license. These can be
+   included either as stand-alone text files, human-readable headers or
+   in the appropriate machine-readable metadata fields within text or
+   binary files as long as those fields can be easily viewed by the user.
+
+3) No Modified Version of the Font Software may use the Reserved Font
+   Name(s) unless explicit written permission is granted by the
+   corresponding Copyright Holder. This restriction only applies to the
+   primary font name as presented to the users.
+
+4) The name(s) of the Copyright Holder(s) or the Author(s) of the Font
+   Software shall not be used to promote, endorse or advertise any
+   Modified Version, except to acknowledge the contribution(s) of the
+   Copyright Holder(s) and the Author(s) or with their explicit written
+   permission.
+
+5) The Font Software, modified or unmodified, in part or in whole, must
+   be distributed entirely under this license, and must not be distributed
+   under any other license. The requirement for fonts to remain under
+   this license does not apply to any document created using the Font
+   Software.
+
+
+ 
+TERMINATION
+This license becomes null and void if any of the above conditions are not met.
+
+ 
+
+DISCLAIMER
+THE FONT SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT
+OF COPYRIGHT, PATENT, TRADEMARK, OR OTHER RIGHT.  IN NO EVENT SHALL THE
+COPYRIGHT HOLDER BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+INCLUDING ANY GENERAL, SPECIAL, INDIRECT, INCIDENTAL, OR CONSEQUENTIAL
+DAMAGES, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF THE USE OR INABILITY TO USE THE FONT SOFTWARE OR FROM OTHER
+DEALINGS IN THE FONT SOFTWARE.
+

assets/shaders/debug/debugfont.fs

@@ -0,0 +1,22 @@
+#version 330 core
+
+out vec4 FragColor;
+in vec3 vPos;
+in vec2 vTexCoord;
+
+uniform sampler2D fontTex;
+uniform int charIndex;
+
+// Main
+
+void main() {
+    int x = (charIndex-32) % 16;
+    int y = (charIndex-32) / 16;
+
+    float fx = float(x) / 16;
+    float fy = float(y) / 8;
+
+   vec4 color = texture(fontTex, vec2(fx, fy) + vTexCoord * vec2(1.f/32, 1.f/16));
+   FragColor = vec3(color) == vec3(0, 0, 0) ? vec4(0, 0, 0, 0) : color;
+//    FragColor = color;
+}

assets/shaders/debug/debugfont.vs

@@ -0,0 +1,12 @@
+#version 330 core
+in vec3 aPos;
+in vec2 aTexCoord;
+
+out vec3 vPos;
+out vec2 vTexCoord;
+void main()
+{
+    gl_Position = vec4(aPos, 1.0);
+    vPos = aPos;
+    vTexCoord = aTexCoord;
+}

assets/shaders/font.fs

@@ -1,22 +1,14 @@
+// https://learnopengl.com/In-Practice/Text-Rendering
+
 #version 330 core
+in vec2 TexCoords;
+out vec4 color;
 
-out vec4 FragColor;
-in vec3 vPos;
-in vec2 vTexCoord;
+uniform sampler2D text;
+uniform vec3 textColor;
 
-uniform sampler2D fontTex;
-uniform int charIndex;
-
-// Main
-
-void main() {
-    int x = (charIndex-32) % 16;
-    int y = (charIndex-32) / 16;
-
-    float fx = float(x) / 16;
-    float fy = float(y) / 8;
-
-   vec4 color = texture(fontTex, vec2(fx, fy) + vTexCoord * vec2(1.f/32, 1.f/16));
-   FragColor = vec3(color) == vec3(0, 0, 0) ? vec4(0, 0, 0, 0) : color;
-//    FragColor = color;
-}
+void main()
+{    
+    vec4 sampled = vec4(1.0, 1.0, 1.0, texture(text, TexCoords).r);
+    color = vec4(textColor, 1.0) * sampled;
+}  

assets/shaders/font.vs

@@ -1,12 +1,13 @@
-#version 330 core
-in vec3 aPos;
-in vec2 aTexCoord;
+// https://learnopengl.com/In-Practice/Text-Rendering
+
+#version 330 core
+layout (location = 0) in vec4 vertex; // <vec2 pos, vec2 tex>
+out vec2 TexCoords;
+
+uniform mat4 projection;
 
-out vec3 vPos;
-out vec2 vTexCoord;
 void main()
 {
-    gl_Position = vec4(aPos, 1.0);
-    vPos = aPos;
-    vTexCoord = aTexCoord;
-}
+    gl_Position = projection * vec4(vertex.xy, 0.0, 1.0);
+    TexCoords = vertex.zw;
+}

core/CMakeLists.txt

@@ -7,6 +7,7 @@ find_package(OpenGL)
 find_package(glm CONFIG REQUIRED)
 find_package(ReactPhysics3D REQUIRED)
 find_package(pugixml 1.15 REQUIRED)
+find_package(Freetype)
 
 find_package(Stb REQUIRED)
 include_directories(${Stb_INCLUDE_DIR})
@@ -44,7 +45,7 @@ list(APPEND SOURCES ${AUTOGEN_OUTS})
 add_library(openblocks STATIC ${SOURCES})
 set_target_properties(openblocks PROPERTIES OUTPUT_NAME "openblocks")
 target_link_directories(openblocks PUBLIC ${LUAJIT_LIBRARY_DIRS})
-target_link_libraries(openblocks ${GLEW_LIBRARIES} ${LUAJIT_LIBRARIES} OpenGL::GL ReactPhysics3D::ReactPhysics3D pugixml::pugixml)
+target_link_libraries(openblocks ${GLEW_LIBRARIES} ${LUAJIT_LIBRARIES} OpenGL::GL ReactPhysics3D::ReactPhysics3D pugixml::pugixml Freetype::Freetype)
 target_include_directories(openblocks PUBLIC "src" "../include" ${LUAJIT_INCLUDE_DIRS})
 add_dependencies(openblocks autogen_build autogen)
 

core/src/rendering/debug/debugrenderer.cpp

@@ -7,19 +7,19 @@
 #include <string>
 
 extern int viewportWidth, viewportHeight;
-extern Texture* fontTexture;
-extern Shader* fontShader;
+extern Texture* debugFontTexture;
+extern Shader* debugFontShader;
 extern Shader* identityShader;
 
 void drawChar(char c, int x, int y, float scale=1.f) {
-    fontShader->use();
-    fontTexture->activate(1);
-    fontShader->set("fontTex", 1);
+    debugFontShader->use();
+    debugFontTexture->activate(1);
+    debugFontShader->set("fontTex", 1);
 
-    fontShader->set("charIndex", (int)c);
+    debugFontShader->set("charIndex", (int)c);
 
     // https://stackoverflow.com/a/10631263
-    int tex = fontShader->getAttribute("aTexCoord");
+    int tex = debugFontShader->getAttribute("aTexCoord");
 
     y = viewportHeight - y - 16*scale;
     float x0 = float(x)/viewportWidth, y0 = float(y)/viewportHeight, x1 = ((float)x + 8*scale)/viewportWidth, y1 = ((float)y + 16*scale)/viewportHeight;

core/src/rendering/font.cpp

@@ -0,0 +1,162 @@
+#include "font.h"
+#include "logger.h"
+#include "panic.h"
+#include "rendering/shader.h"
+
+#include <GL/glew.h>
+#include <GL/gl.h>
+#include <glm/ext/matrix_clip_space.hpp>
+#include <memory>
+
+#include <ft2build.h>
+#include FT_FREETYPE_H
+
+// https://learnopengl.com/In-Practice/Text-Rendering
+
+FT_Library freetype;
+Shader* fontShader;
+
+extern int viewportWidth, viewportHeight;
+
+unsigned int textVAO, textVBO;
+
+void fontInit() {
+    if (FT_Error err = FT_Init_FreeType(&freetype)) {
+        Logger::fatalErrorf("Failed to initialize Freetype: [%d]", err);
+        panic();
+    }
+
+    fontShader = new Shader("assets/shaders/font.vs", "assets/shaders/font.fs");
+
+    // Set up buffer
+    glGenVertexArrays(1, &textVAO);
+    glBindVertexArray(textVAO);
+
+    glGenBuffers(1, &textVBO);    
+    glBindBuffer(GL_ARRAY_BUFFER, textVBO);
+
+    // Dynamic, because we update the vertices often           V~~~~~~~~~~~~~~
+    glBufferData(GL_ARRAY_BUFFER, sizeof(float) * 6 * 4, NULL, GL_DYNAMIC_DRAW);
+    glEnableVertexAttribArray(0);
+
+    glVertexAttribPointer(0, 4, GL_FLOAT, GL_FALSE, 4 * sizeof(float), 0);
+
+    glBindBuffer(GL_ARRAY_BUFFER, 0);
+    glBindVertexArray(0);      
+}
+
+void fontFinish() {
+    if (FT_Error err = FT_Done_FreeType(freetype)) {
+        Logger::fatalErrorf("Failed to free Freetype: [%d]", err);
+        panic();
+    }
+}
+
+std::shared_ptr<Font> loadFont(std::string fontName) {
+    std::string fontPath = "assets/font/" + fontName;
+
+    FT_Face face;
+    if (FT_Error err = FT_New_Face(freetype, fontPath.c_str(), 0, &face)) {
+        Logger::fatalErrorf("Failed to create font '%s': [%d]", fontName.c_str(), err);
+        panic();
+    }
+
+    std::shared_ptr<Font> font = std::make_shared<Font>();
+
+    FT_Set_Pixel_Sizes(face, 0, 48);
+
+    // Load each glyph
+    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
+    for (unsigned char c = 0; c < 128; c++) {
+        // load character glyph 
+        if (FT_Error err = FT_Load_Char(face, c, FT_LOAD_RENDER)) {
+            Logger::errorf("Failed to load glyph %d in font '%s': [%d]", c, fontName.c_str(), err);
+            continue;
+        }
+
+        // Generate texture
+        unsigned int texture;
+        glGenTextures(1, &texture);
+        glBindTexture(GL_TEXTURE_2D, texture);
+        glTexImage2D(
+            GL_TEXTURE_2D,
+            0,
+            GL_RED,
+            face->glyph->bitmap.width,
+            face->glyph->bitmap.rows,
+            0,
+            GL_RED,
+            GL_UNSIGNED_BYTE,
+            face->glyph->bitmap.buffer
+        );
+        // set texture options
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+        // now store character for later use
+        Character character;
+        character.ID = texture;
+        character.size = glm::ivec2(face->glyph->bitmap.width, face->glyph->bitmap.rows);
+        character.bearing = glm::ivec2(face->glyph->bitmap_left, face->glyph->bitmap_top);
+        character.advance = (unsigned int)face->glyph->advance.x;
+        font->characters[c] = character;
+    }
+
+    FT_Done_Face(face);
+
+    return font;
+}
+
+void drawText(std::shared_ptr<Font> font, std::string text, float x, float y, float scale, glm::vec3 color) {
+    // activate corresponding render state
+    glDisable(GL_CULL_FACE);
+    glDisable(GL_DEPTH_TEST);
+
+    fontShader->use();
+    fontShader->set("textColor", color);
+    fontShader->set("text", 0);
+    glActiveTexture(GL_TEXTURE0);
+
+    glm::mat4 projection = glm::ortho(0.0f, (float)viewportWidth, 0.0f, (float)viewportHeight);
+    fontShader->set("projection", projection);
+
+    // This is not in the learnopengl guide but it is VERY important
+    // I'm surprised I missed it but honestly... not so much. I'm an idiot
+    glBindVertexArray(textVAO);
+
+    // iterate through all characters
+    for (size_t i = 0; i < text.size(); i++) {
+        unsigned char c = text[i];
+        Character ch = font->characters[c];
+
+        float xpos = x + ch.bearing.x * scale;
+        float ypos = y - (ch.size.y - ch.bearing.y) * scale;
+
+        float w = ch.size.x * scale;
+        float h = ch.size.y * scale;
+        // render glyph texture over quad
+        glBindTexture(GL_TEXTURE_2D, ch.ID);
+
+        float vertices[6][4] = {
+            { xpos,     ypos + h,   0.0f, 0.0f },            
+            { xpos,     ypos,       0.0f, 1.0f },
+            { xpos + w, ypos,       1.0f, 1.0f },
+
+            { xpos,     ypos + h,   0.0f, 0.0f },
+            { xpos + w, ypos,       1.0f, 1.0f },
+            { xpos + w, ypos + h,   1.0f, 0.0f }           
+        };
+        // render glyph texture over quad
+        glBindTexture(GL_TEXTURE_2D, ch.ID);
+        // update content of VBO memory
+        glBindBuffer(GL_ARRAY_BUFFER, textVBO);
+        glBufferSubData(GL_ARRAY_BUFFER, 0, sizeof(vertices), vertices); 
+        glBindBuffer(GL_ARRAY_BUFFER, 0);
+        // render quad
+        glDrawArrays(GL_TRIANGLES, 0, 6);
+        // now advance cursors for next glyph (note that advance is number of 1/64 pixels)
+        x += (ch.advance >> 6) * scale; // bitshift by 6 to get value in pixels (2^6 = 64)
+    }
+    glBindTexture(GL_TEXTURE_2D, 0);
+}

core/src/rendering/font.h

@@ -0,0 +1,23 @@
+#pragma once
+
+#include <memory>
+#include <string>
+#include <glm/glm.hpp>
+
+// https://learnopengl.com/In-Practice/Text-Rendering
+
+struct Character {
+    unsigned int ID;  // ID handle of the glyph texture
+    glm::ivec2   size;       // Size of glyph
+    glm::ivec2   bearing;    // Offset from baseline to left/top of glyph
+    unsigned int advance;    // Offset to advance to next glyph
+};
+
+struct Font {
+    Character characters[128];
+};
+
+void fontInit();
+void fontFinish();
+std::shared_ptr<Font> loadFont(std::string fontName);
+void drawText(std::shared_ptr<Font> font, std::string text, float x, float y, float scale=1.f, glm::vec3 color = glm::vec3(1,1,1));

core/src/rendering/renderer.cpp

@@ -23,6 +23,7 @@
 #include "math_helper.h"
 #include "objects/service/selection.h"
 #include "partassembly.h"
+#include "rendering/font.h"
 #include "rendering/mesh2d.h"
 #include "rendering/texture.h"
 #include "rendering/torus.h"
@@ -46,14 +47,16 @@ Shader* identityShader = NULL;
 Shader* ghostShader = NULL;
 Shader* wireframeShader = NULL;
 Shader* outlineShader = NULL;
-Shader* fontShader = NULL;
+Shader* debugFontShader = NULL;
 Shader* generic2dShader = NULL;
 extern Camera camera;
 Skybox* skyboxTexture = NULL;
 Texture3D* studsTexture = NULL;
-Texture* fontTexture = NULL;
+Texture* debugFontTexture = NULL;
 Mesh2D* rect2DMesh = NULL;
 
+std::shared_ptr<Font> sansSerif;
+
 bool debugRendererEnabled = false;
 bool wireframeRendering = false;
 
@@ -74,7 +77,7 @@ void renderInit(GLFWwindow* window, int width, int height) {
     glBlendFunc(GL_ONE, GL_ONE_MINUS_SRC_ALPHA);
     // glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 
-    fontTexture = new Texture("assets/textures/debugfnt.bmp", GL_RGB);
+    debugFontTexture = new Texture("assets/textures/debugfnt.bmp", GL_RGB);
 
     skyboxTexture = new Skybox({
         "assets/textures/skybox/null_plainsky512_lf.jpg",
@@ -95,7 +98,7 @@ void renderInit(GLFWwindow* window, int width, int height) {
     ghostShader = new Shader("assets/shaders/ghost.vs", "assets/shaders/ghost.fs");
     wireframeShader = new Shader("assets/shaders/wireframe.vs", "assets/shaders/wireframe.fs");
     outlineShader = new Shader("assets/shaders/outline.vs", "assets/shaders/outline.fs");
-    fontShader = new Shader("assets/shaders/font.vs", "assets/shaders/font.fs");
+    debugFontShader = new Shader("assets/shaders/debug/debugfont.vs", "assets/shaders/debug/debugfont.fs");
     generic2dShader = new Shader("assets/shaders/generic2d.vs", "assets/shaders/generic2d.fs");
 
     // Create mesh for 2d rectangle
@@ -110,6 +113,10 @@ void renderInit(GLFWwindow* window, int width, int height) {
     };
 
     rect2DMesh = new Mesh2D(6, rectVerts);
+
+    // Initialize fonts
+    fontInit();
+    sansSerif = loadFont("LiberationSans-Regular.ttf");
 }
 
 void renderParts() {
@@ -356,7 +363,6 @@ void renderHandles() {
         glm::vec4 screenPos = projection * view * glm::vec4((glm::vec3)cframe.Position(), 1.0f);
         screenPos /= screenPos.w;
         screenPos += 1; screenPos /= 2; screenPos.y = 1 - screenPos.y; screenPos *= glm::vec4(glm::vec2(viewportWidth, viewportHeight), 1, 1);
-        printVec((glm::vec3)screenPos);
         
         drawRect(screenPos.x - 3, screenPos.y - 3, 6, 6, glm::vec3(0, 1, 1));
     }
@@ -664,6 +670,7 @@ void render(GLFWwindow* window) {
         renderDebugInfo();
     // TODO: Make this a debug flag
     // renderAABB();
+
     renderTime = tu_clock_micros() - startTime;
 }
 

deps.txt

@@ -8,4 +8,5 @@ qt6
 reactphysics3d
 pugixml
 luajit
-qscintilla
+qscintilla
+freetype2