Add Nuklear

README.md

@@ -80,6 +80,7 @@ located in the `deps/` directory.
    [glad](https://github.com/Dav1dde/glad) for examples using modern OpenGL
  - [linmath.h](https://github.com/datenwolf/linmath.h) for linear algebra in
    examples
+ - [Nuklear](https://github.com/vurtun/nuklear) for test and example UI
  - [Vulkan headers](https://www.khronos.org/registry/vulkan/) for Vulkan tests
 
 The Vulkan example additionally requires the Vulkan SDK to be installed, or it

deps/nuklear_glfw_gl2.h

+/*
+ * Nuklear - v1.00 - public domain
+ * no warrenty implied; use at your own risk.
+ * authored from 2015-2016 by Micha Mettke
+ */
+/*
+ * ==============================================================
+ *
+ *                              API
+ *
+ * ===============================================================
+ */
+#ifndef NK_GLFW_GL2_H_
+#define NK_GLFW_GL2_H_
+
+#include <GLFW/glfw3.h>
+
+enum nk_glfw_init_state{
+    NK_GLFW3_DEFAULT = 0,
+    NK_GLFW3_INSTALL_CALLBACKS
+};
+NK_API struct nk_context*   nk_glfw3_init(GLFWwindow *win, enum nk_glfw_init_state);
+NK_API void                 nk_glfw3_font_stash_begin(struct nk_font_atlas **atlas);
+NK_API void                 nk_glfw3_font_stash_end(void);
+
+NK_API void                 nk_glfw3_new_frame(void);
+NK_API void                 nk_glfw3_render(enum nk_anti_aliasing , int max_vertex_buffer, int max_element_buffer);
+NK_API void                 nk_glfw3_shutdown(void);
+
+NK_API void                 nk_glfw3_char_callback(GLFWwindow *win, unsigned int codepoint);
+NK_API void                 nk_gflw3_scroll_callback(GLFWwindow *win, double xoff, double yoff);
+
+#endif
+
+/*
+ * ==============================================================
+ *
+ *                          IMPLEMENTATION
+ *
+ * ===============================================================
+ */
+#ifdef NK_GLFW_GL2_IMPLEMENTATION
+
+#ifndef NK_GLFW_TEXT_MAX
+#define NK_GLFW_TEXT_MAX 256
+#endif
+
+struct nk_glfw_device {
+    struct nk_buffer cmds;
+    struct nk_draw_null_texture null;
+    GLuint font_tex;
+};
+
+struct nk_glfw_vertex {
+    float position[2];
+    float uv[2];
+    nk_byte col[4];
+};
+
+static struct nk_glfw {
+    GLFWwindow *win;
+    int width, height;
+    int display_width, display_height;
+    struct nk_glfw_device ogl;
+    struct nk_context ctx;
+    struct nk_font_atlas atlas;
+    struct nk_vec2 fb_scale;
+    unsigned int text[NK_GLFW_TEXT_MAX];
+    int text_len;
+    float scroll;
+} glfw;
+
+NK_INTERN void
+nk_glfw3_device_upload_atlas(const void *image, int width, int height)
+{
+    struct nk_glfw_device *dev = &glfw.ogl;
+    glGenTextures(1, &dev->font_tex);
+    glBindTexture(GL_TEXTURE_2D, dev->font_tex);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, (GLsizei)width, (GLsizei)height, 0,
+                GL_RGBA, GL_UNSIGNED_BYTE, image);
+}
+
+NK_API void
+nk_glfw3_render(enum nk_anti_aliasing AA, int max_vertex_buffer, int max_element_buffer)
+{
+    /* setup global state */
+    struct nk_glfw_device *dev = &glfw.ogl;
+    glPushAttrib(GL_ENABLE_BIT|GL_COLOR_BUFFER_BIT|GL_TRANSFORM_BIT);
+    glDisable(GL_CULL_FACE);
+    glDisable(GL_DEPTH_TEST);
+    glEnable(GL_SCISSOR_TEST);
+    glEnable(GL_BLEND);
+    glEnable(GL_TEXTURE_2D);
+    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+
+    /* setup viewport/project */
+    glViewport(0,0,(GLsizei)glfw.display_width,(GLsizei)glfw.display_height);
+    glMatrixMode(GL_PROJECTION);
+    glPushMatrix();
+    glLoadIdentity();
+    glOrtho(0.0f, glfw.width, glfw.height, 0.0f, -1.0f, 1.0f);
+    glMatrixMode(GL_MODELVIEW);
+    glPushMatrix();
+    glLoadIdentity();
+
+    glEnableClientState(GL_VERTEX_ARRAY);
+    glEnableClientState(GL_TEXTURE_COORD_ARRAY);
+    glEnableClientState(GL_COLOR_ARRAY);
+    {
+        GLsizei vs = sizeof(struct nk_glfw_vertex);
+        size_t vp = offsetof(struct nk_glfw_vertex, position);
+        size_t vt = offsetof(struct nk_glfw_vertex, uv);
+        size_t vc = offsetof(struct nk_glfw_vertex, col);
+
+        /* convert from command queue into draw list and draw to screen */
+        const struct nk_draw_command *cmd;
+        const nk_draw_index *offset = NULL;
+        struct nk_buffer vbuf, ebuf;
+
+        /* fill convert configuration */
+        struct nk_convert_config config;
+        static const struct nk_draw_vertex_layout_element vertex_layout[] = {
+            {NK_VERTEX_POSITION, NK_FORMAT_FLOAT, NK_OFFSETOF(struct nk_glfw_vertex, position)},
+            {NK_VERTEX_TEXCOORD, NK_FORMAT_FLOAT, NK_OFFSETOF(struct nk_glfw_vertex, uv)},
+            {NK_VERTEX_COLOR, NK_FORMAT_R8G8B8A8, NK_OFFSETOF(struct nk_glfw_vertex, col)},
+            {NK_VERTEX_LAYOUT_END}
+        };
+        NK_MEMSET(&config, 0, sizeof(config));
+        config.vertex_layout = vertex_layout;
+        config.vertex_size = sizeof(struct nk_glfw_vertex);
+        config.vertex_alignment = NK_ALIGNOF(struct nk_glfw_vertex);
+        config.null = dev->null;
+        config.circle_segment_count = 22;
+        config.curve_segment_count = 22;
+        config.arc_segment_count = 22;
+        config.global_alpha = 1.0f;
+        config.shape_AA = AA;
+        config.line_AA = AA;
+
+        /* convert shapes into vertexes */
+        nk_buffer_init_default(&vbuf);
+        nk_buffer_init_default(&ebuf);
+        nk_convert(&glfw.ctx, &dev->cmds, &vbuf, &ebuf, &config);
+
+        /* setup vertex buffer pointer */
+        {const void *vertices = nk_buffer_memory_const(&vbuf);
+        glVertexPointer(2, GL_FLOAT, vs, (const void*)((const nk_byte*)vertices + vp));
+        glTexCoordPointer(2, GL_FLOAT, vs, (const void*)((const nk_byte*)vertices + vt));
+        glColorPointer(4, GL_UNSIGNED_BYTE, vs, (const void*)((const nk_byte*)vertices + vc));}
+
+        /* iterate over and execute each draw command */
+        offset = (const nk_draw_index*)nk_buffer_memory_const(&ebuf);
+        nk_draw_foreach(cmd, &glfw.ctx, &dev->cmds)
+        {
+            if (!cmd->elem_count) continue;
+            glBindTexture(GL_TEXTURE_2D, (GLuint)cmd->texture.id);
+            glScissor(
+                (GLint)(cmd->clip_rect.x * glfw.fb_scale.x),
+                (GLint)((glfw.height - (GLint)(cmd->clip_rect.y + cmd->clip_rect.h)) * glfw.fb_scale.y),
+                (GLint)(cmd->clip_rect.w * glfw.fb_scale.x),
+                (GLint)(cmd->clip_rect.h * glfw.fb_scale.y));
+            glDrawElements(GL_TRIANGLES, (GLsizei)cmd->elem_count, GL_UNSIGNED_SHORT, offset);
+            offset += cmd->elem_count;
+        }
+        nk_clear(&glfw.ctx);
+        nk_buffer_free(&vbuf);
+        nk_buffer_free(&ebuf);
+    }
+
+    /* default OpenGL state */
+    glDisableClientState(GL_VERTEX_ARRAY);
+    glDisableClientState(GL_TEXTURE_COORD_ARRAY);
+    glDisableClientState(GL_COLOR_ARRAY);
+
+    glDisable(GL_CULL_FACE);
+    glDisable(GL_DEPTH_TEST);
+    glDisable(GL_SCISSOR_TEST);
+    glDisable(GL_BLEND);
+    glDisable(GL_TEXTURE_2D);
+
+    glBindTexture(GL_TEXTURE_2D, 0);
+    glMatrixMode(GL_MODELVIEW);
+    glPopMatrix();
+    glMatrixMode(GL_PROJECTION);
+    glPopMatrix();
+    glPopAttrib();
+}
+
+NK_API void
+nk_glfw3_char_callback(GLFWwindow *win, unsigned int codepoint)
+{
+    (void)win;
+    if (glfw.text_len < NK_GLFW_TEXT_MAX)
+        glfw.text[glfw.text_len++] = codepoint;
+}
+
+NK_API void
+nk_gflw3_scroll_callback(GLFWwindow *win, double xoff, double yoff)
+{
+    (void)win; (void)xoff;
+    glfw.scroll += (float)yoff;
+}
+
+NK_INTERN void
+nk_glfw3_clipbard_paste(nk_handle usr, struct nk_text_edit *edit)
+{
+    const char *text = glfwGetClipboardString(glfw.win);
+    if (text) nk_textedit_paste(edit, text, nk_strlen(text));
+    (void)usr;
+}
+
+NK_INTERN void
+nk_glfw3_clipbard_copy(nk_handle usr, const char *text, int len)
+{
+    char *str = 0;
+    (void)usr;
+    if (!len) return;
+    str = (char*)malloc((size_t)len+1);
+    if (!str) return;
+    memcpy(str, text, (size_t)len);
+    str[len] = '\0';
+    glfwSetClipboardString(glfw.win, str);
+    free(str);
+}
+
+NK_API struct nk_context*
+nk_glfw3_init(GLFWwindow *win, enum nk_glfw_init_state init_state)
+{
+    glfw.win = win;
+    if (init_state == NK_GLFW3_INSTALL_CALLBACKS) {
+        glfwSetScrollCallback(win, nk_gflw3_scroll_callback);
+        glfwSetCharCallback(win, nk_glfw3_char_callback);
+    }
+
+    nk_init_default(&glfw.ctx, 0);
+    glfw.ctx.clip.copy = nk_glfw3_clipbard_copy;
+    glfw.ctx.clip.paste = nk_glfw3_clipbard_paste;
+    glfw.ctx.clip.userdata = nk_handle_ptr(0);
+    nk_buffer_init_default(&glfw.ogl.cmds);
+    return &glfw.ctx;
+}
+
+NK_API void
+nk_glfw3_font_stash_begin(struct nk_font_atlas **atlas)
+{
+    nk_font_atlas_init_default(&glfw.atlas);
+    nk_font_atlas_begin(&glfw.atlas);
+    *atlas = &glfw.atlas;
+}
+
+NK_API void
+nk_glfw3_font_stash_end(void)
+{
+    const void *image; int w, h;
+    image = nk_font_atlas_bake(&glfw.atlas, &w, &h, NK_FONT_ATLAS_RGBA32);
+    nk_glfw3_device_upload_atlas(image, w, h);
+    nk_font_atlas_end(&glfw.atlas, nk_handle_id((int)glfw.ogl.font_tex), &glfw.ogl.null);
+    if (glfw.atlas.default_font)
+        nk_style_set_font(&glfw.ctx, &glfw.atlas.default_font->handle);
+}
+
+NK_API void
+nk_glfw3_new_frame(void)
+{
+    int i;
+    double x, y;
+    struct nk_context *ctx = &glfw.ctx;
+    struct GLFWwindow *win = glfw.win;
+
+    glfwGetWindowSize(win, &glfw.width, &glfw.height);
+    glfwGetFramebufferSize(win, &glfw.display_width, &glfw.display_height);
+    glfw.fb_scale.x = (float)glfw.display_width/(float)glfw.width;
+    glfw.fb_scale.y = (float)glfw.display_height/(float)glfw.height;
+
+    nk_input_begin(ctx);
+    for (i = 0; i < glfw.text_len; ++i)
+        nk_input_unicode(ctx, glfw.text[i]);
+
+    /* optional grabbing behavior */
+    if (ctx->input.mouse.grab)
+        glfwSetInputMode(glfw.win, GLFW_CURSOR, GLFW_CURSOR_HIDDEN);
+    else if (ctx->input.mouse.ungrab)
+        glfwSetInputMode(glfw.win, GLFW_CURSOR, GLFW_CURSOR_NORMAL);
+
+    nk_input_key(ctx, NK_KEY_DEL, glfwGetKey(win, GLFW_KEY_DELETE) == GLFW_PRESS);
+    nk_input_key(ctx, NK_KEY_ENTER, glfwGetKey(win, GLFW_KEY_ENTER) == GLFW_PRESS);
+    nk_input_key(ctx, NK_KEY_TAB, glfwGetKey(win, GLFW_KEY_TAB) == GLFW_PRESS);
+    nk_input_key(ctx, NK_KEY_BACKSPACE, glfwGetKey(win, GLFW_KEY_BACKSPACE) == GLFW_PRESS);
+    nk_input_key(ctx, NK_KEY_UP, glfwGetKey(win, GLFW_KEY_UP) == GLFW_PRESS);
+    nk_input_key(ctx, NK_KEY_DOWN, glfwGetKey(win, GLFW_KEY_DOWN) == GLFW_PRESS);
+    nk_input_key(ctx, NK_KEY_TEXT_START, glfwGetKey(win, GLFW_KEY_HOME) == GLFW_PRESS);
+    nk_input_key(ctx, NK_KEY_TEXT_END, glfwGetKey(win, GLFW_KEY_END) == GLFW_PRESS);
+    nk_input_key(ctx, NK_KEY_SCROLL_START, glfwGetKey(win, GLFW_KEY_HOME) == GLFW_PRESS);
+    nk_input_key(ctx, NK_KEY_SCROLL_END, glfwGetKey(win, GLFW_KEY_END) == GLFW_PRESS);
+    nk_input_key(ctx, NK_KEY_SCROLL_DOWN, glfwGetKey(win, GLFW_KEY_PAGE_DOWN) == GLFW_PRESS);
+    nk_input_key(ctx, NK_KEY_SCROLL_UP, glfwGetKey(win, GLFW_KEY_PAGE_UP) == GLFW_PRESS);
+    nk_input_key(ctx, NK_KEY_SHIFT, glfwGetKey(win, GLFW_KEY_LEFT_SHIFT) == GLFW_PRESS||
+                                    glfwGetKey(win, GLFW_KEY_RIGHT_SHIFT) == GLFW_PRESS);
+
+    if (glfwGetKey(win, GLFW_KEY_LEFT_CONTROL) == GLFW_PRESS ||
+        glfwGetKey(win, GLFW_KEY_RIGHT_CONTROL) == GLFW_PRESS) {
+        nk_input_key(ctx, NK_KEY_COPY, glfwGetKey(win, GLFW_KEY_C) == GLFW_PRESS);
+        nk_input_key(ctx, NK_KEY_PASTE, glfwGetKey(win, GLFW_KEY_P) == GLFW_PRESS);
+        nk_input_key(ctx, NK_KEY_CUT, glfwGetKey(win, GLFW_KEY_X) == GLFW_PRESS);
+        nk_input_key(ctx, NK_KEY_TEXT_UNDO, glfwGetKey(win, GLFW_KEY_Z) == GLFW_PRESS);
+        nk_input_key(ctx, NK_KEY_TEXT_REDO, glfwGetKey(win, GLFW_KEY_R) == GLFW_PRESS);
+        nk_input_key(ctx, NK_KEY_TEXT_WORD_LEFT, glfwGetKey(win, GLFW_KEY_LEFT) == GLFW_PRESS);
+        nk_input_key(ctx, NK_KEY_TEXT_WORD_RIGHT, glfwGetKey(win, GLFW_KEY_RIGHT) == GLFW_PRESS);
+        nk_input_key(ctx, NK_KEY_TEXT_LINE_START, glfwGetKey(win, GLFW_KEY_B) == GLFW_PRESS);
+        nk_input_key(ctx, NK_KEY_TEXT_LINE_END, glfwGetKey(win, GLFW_KEY_E) == GLFW_PRESS);
+    } else {
+        nk_input_key(ctx, NK_KEY_LEFT, glfwGetKey(win, GLFW_KEY_LEFT) == GLFW_PRESS);
+        nk_input_key(ctx, NK_KEY_RIGHT, glfwGetKey(win, GLFW_KEY_RIGHT) == GLFW_PRESS);
+        nk_input_key(ctx, NK_KEY_COPY, 0);
+        nk_input_key(ctx, NK_KEY_PASTE, 0);
+        nk_input_key(ctx, NK_KEY_CUT, 0);
+        nk_input_key(ctx, NK_KEY_SHIFT, 0);
+    }
+
+    glfwGetCursorPos(win, &x, &y);
+    nk_input_motion(ctx, (int)x, (int)y);
+    if (ctx->input.mouse.grabbed) {
+        glfwSetCursorPos(glfw.win, ctx->input.mouse.prev.x, ctx->input.mouse.prev.y);
+        ctx->input.mouse.pos.x = ctx->input.mouse.prev.x;
+        ctx->input.mouse.pos.y = ctx->input.mouse.prev.y;
+    }
+
+    nk_input_button(ctx, NK_BUTTON_LEFT, (int)x, (int)y, glfwGetMouseButton(win, GLFW_MOUSE_BUTTON_LEFT) == GLFW_PRESS);
+    nk_input_button(ctx, NK_BUTTON_MIDDLE, (int)x, (int)y, glfwGetMouseButton(win, GLFW_MOUSE_BUTTON_MIDDLE) == GLFW_PRESS);
+    nk_input_button(ctx, NK_BUTTON_RIGHT, (int)x, (int)y, glfwGetMouseButton(win, GLFW_MOUSE_BUTTON_RIGHT) == GLFW_PRESS);
+    nk_input_scroll(ctx, glfw.scroll);
+    nk_input_end(&glfw.ctx);
+    glfw.text_len = 0;
+    glfw.scroll = 0;
+}
+
+NK_API
+void nk_glfw3_shutdown(void)
+{
+    struct nk_glfw_device *dev = &glfw.ogl;
+    nk_font_atlas_clear(&glfw.atlas);
+    nk_free(&glfw.ctx);
+    glDeleteTextures(1, &dev->font_tex);
+    nk_buffer_free(&dev->cmds);
+    memset(&glfw, 0, sizeof(glfw));
+}
+
+#endif