Added text rendering to show fps

Makefile

@@ -1,15 +1,16 @@
 CC := g++
 CFLAGS := -std=c++17 -O3
 LDFLAGS := -ldl -lglfw
+INCLUDES := -I/usr/include/freetype2/ -I/usr/include/libpng16
 
-ghostland: glad.o ghostland.o stb_image.o collisions.o player.o shader.o ghost.o
+ghostland: glad.o ghostland.o stb_image.o collisions.o player.o shader.o ghost.o text.o
-	$(CC) -o ghostland glad.o ghostland.o stb_image.o collisions.o player.o shader.o ghost.o $(LDFLAGS) $(CFLAGS)
+	$(CC) -o ghostland glad.o ghostland.o stb_image.o collisions.o player.o shader.o ghost.o text.o /usr/lib/x86_64-linux-gnu/libfreetype.so $(LDFLAGS) $(CFLAGS)
 
 glad.o: glad.c
 	$(CC) -c -o glad.o glad.c $(CFLAGS)
 
 ghostland.o: ghostland.cpp
-	$(CC) -c -o ghostland.o ghostland.cpp $(CFLAGS)
+	$(CC) -c -o ghostland.o ghostland.cpp $(CFLAGS) $(INCLUDES)
 
 stb_image.o: stb_image.c
 	$(CC) -c -o stb_image.o stb_image.c $(CFLAGS)
@@ -26,5 +27,8 @@ shader.o: shader.cpp shader.h
 ghost.o: ghost.cpp ghost.h
 	$(CC) -c -o ghost.o ghost.cpp $(CFLAGS)
 
+text.o: text.cpp text.h
+	$(CC) -c -o text.o text.cpp $(CFLAGS) $(INCLUDES)
+
 clean:
 	rm -f *.o ghostland

ghostland.cpp

@@ -2,6 +2,7 @@
 #include <stdio.h>
 #include <glad/glad.h>
 #include <GLFW/glfw3.h>
+
 #include <stb_image.h>
 
 #include <glm/glm.hpp>
@@ -17,6 +18,7 @@
 #include "player.h"
 #include "shader.h"
 #include "ghost.h"
+#include "text.h"
 
 void framebuffer_size_callback(GLFWwindow* window, int width, int height);
 void mouse_callback(GLFWwindow* window, double xpos, double ypos);
@@ -172,7 +174,7 @@ int main(int argc, char *argv[])
     }
 
     glEnable(GL_DEPTH_TEST);
-
+    //glEnable(GL_CULL_FACE);
     glEnable(GL_BLEND);
     glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 
@@ -314,6 +316,14 @@ int main(int argc, char *argv[])
     glGenerateMipmap(GL_TEXTURE_2D);
     stbi_image_free(ghost_data);
 
+    // do stuff for text
+    int text_program;
+    if (init_text(&text_program) < 0) {
+        printf("Failed to load text module!\n");
+        glfwTerminate();
+        return -1;
+    }
+ 
     // TODO move these into config file??
     int time_secI = 0, num_frames = 1;
     float time_sec;
@@ -333,13 +343,16 @@ int main(int argc, char *argv[])
         ghosts.push_back(new Ghost(xmin_wall, xmax_wall, zmin_wall, zmax_wall));
     }
 
-    player->mouse_callback(window, WINDOWWIDTH/2, WINDOWHEIGHT/2);
+    player->mouse_callback(window, WINDOWWIDTH, WINDOWHEIGHT);
+
+    int FPS = -1;
 
     while (!glfwWindowShouldClose(window))
     {
         float current_frame = static_cast<float>(glfwGetTime());
         int current_frameI = (int)current_frame;
-        if (current_frameI != time_secI) {
+        if (current_frameI != time_secI) {  // show stats every second
+            FPS = num_frames;
             glm::vec3 player_pos = player->get_position();
             float yaw, pitch;
             yaw = player->get_yaw();
@@ -358,7 +371,7 @@ int main(int argc, char *argv[])
             if (trail_sz < trailmax) {
                 trail_sz++;
             }
-        } else {
+        } else { // otherwise increase number of frames
             num_frames++;
         }
         timed = current_frame - last_frame;
@@ -463,6 +476,15 @@ int main(int argc, char *argv[])
             glDrawArrays(GL_TRIANGLES, 0, (3 + 3 + 2) * 6);
         }
 
+        if (FPS != -1) {
+            glUseProgram(text_program);
+            projection = glm::ortho(0.0f, static_cast<float>(WINDOWWIDTH), 0.0f, static_cast<float>(WINDOWHEIGHT));
+            set_uniform(text_program, projectionC, projection);
+            char fps_buff[256];
+            sprintf(fps_buff, "FPS: %d", FPS);
+            render_text(text_program, std::string(fps_buff), 25.0F, WINDOWHEIGHT - 35.0f, 0.5f, glm::vec3(1.0f, 0.0f, 0.0f));
+        }
+
         player->apply_movement(timed);
 
         glfwSwapBuffers(window);

maze.txt

@@ -1,4 +1,4 @@
-845.0 2.5 -5.0 270.0
+845.0 2.5 -5.0 0.0
 6498
 -0.5 0.0 0.5 0.0 0.0 1.0
 959.5 0.0 0.5 0.0 0.0 1.0

text.cpp

@@ -0,0 +1,141 @@
+#include <glm/glm.hpp>
+#include <map>
+#include <glad/glad.h>
+
+#include "text.h"
+#include "shader.h"
+
+FT_Library ft;
+FT_Face face;
+
+const char *textcolorC = "textColor";
+
+unsigned int textVAO, textVBO;
+
+struct character_t {
+    unsigned int texture_id;
+    glm::ivec2 size;
+    glm::ivec2 bearing;
+    unsigned int advance;
+};
+
+std::map<char, character_t> glyph_to_character;
+
+int init_text(int *shader) {
+
+    if (FT_Init_FreeType(&ft)) {
+        printf("Could not init freetype library.\n");
+        return -1;
+    }
+
+    if (FT_New_Face(ft, "fonts/LiberationSerif-Regular.ttf", 0, &face)) {
+        printf("Could not font face.\n");
+        return -1;
+    }
+    
+    FT_Set_Pixel_Sizes(face, 0, 48);
+    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
+
+    for (unsigned char c = 0; c < 128; c++) {
+
+        if (FT_Load_Char(face, c, FT_LOAD_RENDER)) {
+            printf("Failed to load glyph: %c\n", c);
+            return -1;
+        }
+
+        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
+        );
+        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);
+
+        character_t character = {
+            texture,
+            glm::ivec2(face->glyph->bitmap.width, face->glyph->bitmap.rows),
+            glm::ivec2(face->glyph->bitmap_left, face->glyph->bitmap_top),
+            static_cast<unsigned int>(face->glyph->advance.x),
+        };
+
+        glyph_to_character.insert(std::pair<char, character_t>(c, character));
+
+    }
+
+    glBindTexture(GL_TEXTURE_2D, 0);
+
+    FT_Done_Face(face);
+    FT_Done_FreeType(ft);
+
+    // configure textVAO/textVBO for texture quads
+    // -----------------------------------
+    glGenVertexArrays(1, &textVAO);
+    glGenBuffers(1, &textVBO);
+    glBindVertexArray(textVAO);
+    glBindBuffer(GL_ARRAY_BUFFER, textVBO);
+    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);
+
+    *shader = create_shader_program("textshader.glsl", "textfragshader.glsl");
+    if (*shader < 0) {
+        printf("Got error compiling text shader!\n");
+        return -1;
+    }
+
+    return 0;
+
+}
+
+void render_text(int shader, std::string text, float x, float y, float scale, glm::vec3 color) {
+
+    set_uniform(shader, textcolorC, color);
+    glActiveTexture(GL_TEXTURE0);
+    glBindVertexArray(textVAO);
+
+    std::string::const_iterator c;
+    for (c = text.begin(); c != text.end(); c++) {
+        character_t ch = glyph_to_character[*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;
+
+        float vertices[24] = {
+            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,
+        };
+        glBindTexture(GL_TEXTURE_2D, ch.texture_id);
+        glBindBuffer(GL_ARRAY_BUFFER, textVBO);
+        glBufferSubData(GL_ARRAY_BUFFER, 0, sizeof(float) * (2 + 2) * 6, vertices);
+
+        glBindBuffer(GL_ARRAY_BUFFER, 0);
+        glDrawArrays(GL_TRIANGLES, 0, (2 + 2) * 6);
+
+        x += (ch.advance >> 6) * scale;
+
+    }
+
+    glBindVertexArray(0);
+    glBindTexture(GL_TEXTURE_2D, 0);
+
+}

text.h

@@ -0,0 +1,13 @@
+#ifndef TEXT_H
+#define TEXT_H
+
+#include <stdio.h>
+#include <string>
+
+#include <ft2build.h>
+#include FT_FREETYPE_H
+
+int init_text(int *shader);
+void render_text(int shader, std::string text, float x, float y, float scale, glm::vec3 color);
+
+#endif

textfragshader.glsl

@@ -0,0 +1,12 @@
+#version 460 core
+in vec2 TexCoords;
+out vec4 color;
+
+uniform sampler2D text;
+uniform vec3 textColor;
+
+void main()
+{    
+    vec4 sampled = vec4(1.0, 1.0, 1.0, texture(text, TexCoords).r);
+    color = vec4(textColor, 1.0) * sampled;
+}

textshader.glsl

@@ -0,0 +1,11 @@
+#version 460 core
+layout (location = 0) in vec4 vertex; // <vec2 pos, vec2 tex>
+out vec2 TexCoords;
+
+uniform mat4 projection;
+
+void main()
+{
+    gl_Position = projection * vec4(vertex.xy, 0.0f, 1.0);
+    TexCoords = vertex.zw;
+}