From b6d85b9e31917a6573b1f833b3d6cf7129337960 Mon Sep 17 00:00:00 2001 From: Matthias Clasen Date: Wed, 17 Jan 2018 14:39:46 -0500 Subject: [PATCH] gtk-demo: Add gears to the bowl Just for fun. --- demos/gtk-demo/gtkgears.c | 960 ++++++++++++++++++++++++++++++++++++ demos/gtk-demo/gtkgears.h | 48 ++ demos/gtk-demo/meson.build | 4 +- demos/gtk-demo/widgetbowl.c | 12 + 4 files changed, 1023 insertions(+), 1 deletion(-) create mode 100644 demos/gtk-demo/gtkgears.c create mode 100644 demos/gtk-demo/gtkgears.h diff --git a/demos/gtk-demo/gtkgears.c b/demos/gtk-demo/gtkgears.c new file mode 100644 index 0000000000..32a24dafb4 --- /dev/null +++ b/demos/gtk-demo/gtkgears.c @@ -0,0 +1,960 @@ +/* The rendering code in here is taken from es2gears, which has the + * following copyright notice: + * + * Copyright (C) 1999-2001 Brian Paul All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included + * in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN + * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + * + * Ported to GLES2. + * Kristian Høgsberg + * May 3, 2010 + * + * Improve GLES2 port: + * * Refactor gear drawing. + * * Use correct normals for surfaces. + * * Improve shader. + * * Use perspective projection transformation. + * * Add FPS count. + * * Add comments. + * Alexandros Frantzis + * Jul 13, 2010 + */ + +#include "config.h" + +#include +#include +#include +#include + +#include "gtkgears.h" + +#define STRIPS_PER_TOOTH 7 +#define VERTICES_PER_TOOTH 34 +#define GEAR_VERTEX_STRIDE 6 + +#ifndef HAVE_SINCOS +static void +sincos (double x, double *_sin, double *_cos) +{ + *_sin = sin (x); + *_cos = cos (x); +} +#endif + +/** + * Struct describing the vertices in triangle strip + */ +struct vertex_strip { + /** The first vertex in the strip */ + GLint first; + /** The number of consecutive vertices in the strip after the first */ + GLint count; +}; + +/* Each vertex consist of GEAR_VERTEX_STRIDE GLfloat attributes */ +typedef GLfloat GearVertex[GEAR_VERTEX_STRIDE]; + +/** + * Struct representing a gear. + */ +struct gear { + /** The array of vertices comprising the gear */ + GearVertex *vertices; + /** The number of vertices comprising the gear */ + int nvertices; + /** The array of triangle strips comprising the gear */ + struct vertex_strip *strips; + /** The number of triangle strips comprising the gear */ + int nstrips; +}; + +typedef struct { + /* The view rotation [x, y, z] */ + GLfloat view_rot[GTK_GEARS_N_AXIS]; + + /* The Vertex Array Object */ + GLuint vao; + + /* The shader program */ + GLuint program; + + /* The gears */ + struct gear *gear1; + struct gear *gear2; + struct gear *gear3; + + /** The Vertex Buffer Object holding the vertices in the graphics card */ + GLuint gear_vbo[3]; + + /** The location of the shader uniforms */ + GLuint ModelViewProjectionMatrix_location; + GLuint NormalMatrix_location; + GLuint LightSourcePosition_location; + GLuint MaterialColor_location; + + /* The current gear rotation angle */ + GLfloat angle; + + /* The projection matrix */ + GLfloat ProjectionMatrix[16]; + + /* The direction of the directional light for the scene */ + GLfloat LightSourcePosition[4]; + + gint64 first_frame_time; + guint tick; + GtkLabel *fps_label; +} GtkGearsPrivate; + +G_DEFINE_TYPE_WITH_PRIVATE (GtkGears, gtk_gears, GTK_TYPE_GL_AREA) + +static gboolean gtk_gears_render (GtkGLArea *area, + GdkGLContext *context); +static void gtk_gears_reshape (GtkGLArea *area, + int width, + int height); +static void gtk_gears_realize (GtkWidget *widget); +static void gtk_gears_unrealize (GtkWidget *widget); +static gboolean gtk_gears_tick (GtkWidget *widget, + GdkFrameClock *frame_clock, + gpointer user_data); + +static void destroy_gear (struct gear *g); + +GtkWidget * +gtk_gears_new (void) +{ + return g_object_new (gtk_gears_get_type (), + "has-depth-buffer", TRUE, + NULL); +} + +static void +gtk_gears_init (GtkGears *gears) +{ + GtkGearsPrivate *priv = gtk_gears_get_instance_private (gears); + + priv->view_rot[GTK_GEARS_X_AXIS] = 20.0; + priv->view_rot[GTK_GEARS_Y_AXIS] = 30.0; + priv->view_rot[GTK_GEARS_Z_AXIS] = 20.0; + + priv->LightSourcePosition[0] = 5.0; + priv->LightSourcePosition[1] = 5.0; + priv->LightSourcePosition[2] = 10.0; + priv->LightSourcePosition[3] = 1.0; + + priv->tick = gtk_widget_add_tick_callback (GTK_WIDGET (gears), gtk_gears_tick, gears, NULL); +} + +static void +gtk_gears_finalize (GObject *obj) +{ + GtkGears *gears = GTK_GEARS (obj); + GtkGearsPrivate *priv = gtk_gears_get_instance_private (gears); + + gtk_widget_remove_tick_callback (GTK_WIDGET (gears), priv->tick); + + g_clear_object (&priv->fps_label); + + g_clear_pointer (&priv->gear1, destroy_gear); + g_clear_pointer (&priv->gear2, destroy_gear); + g_clear_pointer (&priv->gear3, destroy_gear); + + G_OBJECT_CLASS (gtk_gears_parent_class)->finalize (obj); +} + +static void +gtk_gears_class_init (GtkGearsClass *klass) +{ + GTK_GL_AREA_CLASS (klass)->render = gtk_gears_render; + GTK_GL_AREA_CLASS (klass)->resize = gtk_gears_reshape; + + GTK_WIDGET_CLASS (klass)->realize = gtk_gears_realize; + GTK_WIDGET_CLASS (klass)->unrealize = gtk_gears_unrealize; + + G_OBJECT_CLASS (klass)->finalize = gtk_gears_finalize; +} + +/* + * Fills a gear vertex. + * + * @param v the vertex to fill + * @param x the x coordinate + * @param y the y coordinate + * @param z the z coortinate + * @param n pointer to the normal table + * + * @return the operation error code + */ +static GearVertex * +vert (GearVertex *v, + GLfloat x, + GLfloat y, + GLfloat z, + GLfloat n[3]) +{ + v[0][0] = x; + v[0][1] = y; + v[0][2] = z; + v[0][3] = n[0]; + v[0][4] = n[1]; + v[0][5] = n[2]; + + return v + 1; +} + +static void +destroy_gear (struct gear *g) +{ + g_free (g->strips); + g_free (g); +} + +/** + * Create a gear wheel. + * + * @param inner_radius radius of hole at center + * @param outer_radius radius at center of teeth + * @param width width of gear + * @param teeth number of teeth + * @param tooth_depth depth of tooth + * + * @return pointer to the constructed struct gear + */ +static struct gear * +create_gear (GLfloat inner_radius, + GLfloat outer_radius, + GLfloat width, + GLint teeth, + GLfloat tooth_depth) +{ + GLfloat r0, r1, r2; + GLfloat da; + GearVertex *v; + struct gear *gear; + double s[5], c[5]; + GLfloat normal[3]; + int cur_strip = 0; + int i; + + /* Allocate memory for the gear */ + gear = g_malloc (sizeof *gear); + + /* Calculate the radii used in the gear */ + r0 = inner_radius; + r1 = outer_radius - tooth_depth / 2.0; + r2 = outer_radius + tooth_depth / 2.0; + + da = 2.0 * M_PI / teeth / 4.0; + + /* Allocate memory for the triangle strip information */ + gear->nstrips = STRIPS_PER_TOOTH * teeth; + gear->strips = g_malloc0_n (gear->nstrips, sizeof (*gear->strips)); + + /* Allocate memory for the vertices */ + gear->vertices = g_malloc0_n (VERTICES_PER_TOOTH * teeth, sizeof(*gear->vertices)); + v = gear->vertices; + + for (i = 0; i < teeth; i++) { + /* A set of macros for making the creation of the gears easier */ +#define GEAR_POINT(p, r, da) do { p.x = (r) * c[(da)]; p.y = (r) * s[(da)]; } while(0) +#define SET_NORMAL(x, y, z) do { \ + normal[0] = (x); normal[1] = (y); normal[2] = (z); \ +} while(0) + +#define GEAR_VERT(v, point, sign) vert((v), p[(point)].x, p[(point)].y, (sign) * width * 0.5, normal) + +#define START_STRIP do { \ + gear->strips[cur_strip].first = v - gear->vertices; \ +} while(0); + +#define END_STRIP do { \ + int _tmp = (v - gear->vertices); \ + gear->strips[cur_strip].count = _tmp - gear->strips[cur_strip].first; \ + cur_strip++; \ +} while (0) + +#define QUAD_WITH_NORMAL(p1, p2) do { \ + SET_NORMAL((p[(p1)].y - p[(p2)].y), -(p[(p1)].x - p[(p2)].x), 0); \ + v = GEAR_VERT(v, (p1), -1); \ + v = GEAR_VERT(v, (p1), 1); \ + v = GEAR_VERT(v, (p2), -1); \ + v = GEAR_VERT(v, (p2), 1); \ +} while(0) + struct point { + GLfloat x; + GLfloat y; + }; + + /* Create the 7 points (only x,y coords) used to draw a tooth */ + struct point p[7]; + + /* Calculate needed sin/cos for varius angles */ + sincos(i * 2.0 * G_PI / teeth + da * 0, &s[0], &c[0]); + sincos(i * 2.0 * M_PI / teeth + da * 1, &s[1], &c[1]); + sincos(i * 2.0 * M_PI / teeth + da * 2, &s[2], &c[2]); + sincos(i * 2.0 * M_PI / teeth + da * 3, &s[3], &c[3]); + sincos(i * 2.0 * M_PI / teeth + da * 4, &s[4], &c[4]); + + GEAR_POINT(p[0], r2, 1); + GEAR_POINT(p[1], r2, 2); + GEAR_POINT(p[2], r1, 0); + GEAR_POINT(p[3], r1, 3); + GEAR_POINT(p[4], r0, 0); + GEAR_POINT(p[5], r1, 4); + GEAR_POINT(p[6], r0, 4); + + /* Front face */ + START_STRIP; + SET_NORMAL(0, 0, 1.0); + v = GEAR_VERT(v, 0, +1); + v = GEAR_VERT(v, 1, +1); + v = GEAR_VERT(v, 2, +1); + v = GEAR_VERT(v, 3, +1); + v = GEAR_VERT(v, 4, +1); + v = GEAR_VERT(v, 5, +1); + v = GEAR_VERT(v, 6, +1); + END_STRIP; + + /* Inner face */ + START_STRIP; + QUAD_WITH_NORMAL(4, 6); + END_STRIP; + + /* Back face */ + START_STRIP; + SET_NORMAL(0, 0, -1.0); + v = GEAR_VERT(v, 6, -1); + v = GEAR_VERT(v, 5, -1); + v = GEAR_VERT(v, 4, -1); + v = GEAR_VERT(v, 3, -1); + v = GEAR_VERT(v, 2, -1); + v = GEAR_VERT(v, 1, -1); + v = GEAR_VERT(v, 0, -1); + END_STRIP; + + /* Outer face */ + START_STRIP; + QUAD_WITH_NORMAL(0, 2); + END_STRIP; + + START_STRIP; + QUAD_WITH_NORMAL(1, 0); + END_STRIP; + + START_STRIP; + QUAD_WITH_NORMAL(3, 1); + END_STRIP; + + START_STRIP; + QUAD_WITH_NORMAL(5, 3); + END_STRIP; + } + + gear->nvertices = (v - gear->vertices); + + return gear; +} + +/** + * Multiplies two 4x4 matrices. + * + * The result is stored in matrix m. + * + * @param m the first matrix to multiply + * @param n the second matrix to multiply + */ +static void +multiply (GLfloat *m, const GLfloat *n) +{ + GLfloat tmp[16]; + const GLfloat *row, *column; + div_t d; + int i, j; + + for (i = 0; i < 16; i++) { + tmp[i] = 0; + d = div(i, 4); + row = n + d.quot * 4; + column = m + d.rem; + for (j = 0; j < 4; j++) + tmp[i] += row[j] * column[j * 4]; + } + memcpy(m, &tmp, sizeof tmp); +} + +/** + * Rotates a 4x4 matrix. + * + * @param[in,out] m the matrix to rotate + * @param angle the angle to rotate + * @param x the x component of the direction to rotate to + * @param y the y component of the direction to rotate to + * @param z the z component of the direction to rotate to + */ +static void +rotate(GLfloat *m, GLfloat angle, GLfloat x, GLfloat y, GLfloat z) +{ + double s = sin (angle); + double c = cos (angle); + + GLfloat r[16] = { + x * x * (1 - c) + c, y * x * (1 - c) + z * s, x * z * (1 - c) - y * s, 0, + x * y * (1 - c) - z * s, y * y * (1 - c) + c, y * z * (1 - c) + x * s, 0, + x * z * (1 - c) + y * s, y * z * (1 - c) - x * s, z * z * (1 - c) + c, 0, + 0, 0, 0, 1 + }; + + multiply(m, r); +} + +/** + * Translates a 4x4 matrix. + * + * @param[in,out] m the matrix to translate + * @param x the x component of the direction to translate to + * @param y the y component of the direction to translate to + * @param z the z component of the direction to translate to + */ +static void +translate(GLfloat *m, GLfloat x, GLfloat y, GLfloat z) +{ + GLfloat t[16] = { 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, x, y, z, 1 }; + + multiply(m, t); +} + +/** + * Creates an identity 4x4 matrix. + * + * @param m the matrix make an identity matrix + */ +static void +identity(GLfloat *m) +{ + GLfloat t[16] = { + 1.0, 0.0, 0.0, 0.0, + 0.0, 1.0, 0.0, 0.0, + 0.0, 0.0, 1.0, 0.0, + 0.0, 0.0, 0.0, 1.0, + }; + + memcpy(m, t, sizeof(t)); +} + +/** + * Transposes a 4x4 matrix. + * + * @param m the matrix to transpose + */ +static void +transpose(GLfloat *m) +{ + GLfloat t[16] = { + m[0], m[4], m[8], m[12], + m[1], m[5], m[9], m[13], + m[2], m[6], m[10], m[14], + m[3], m[7], m[11], m[15]}; + + memcpy(m, t, sizeof(t)); +} + +/** + * Inverts a 4x4 matrix. + * + * This function can currently handle only pure translation-rotation matrices. + * Read http://www.gamedev.net/community/forums/topic.asp?topic_id=425118 + * for an explanation. + */ +static void +invert(GLfloat *m) +{ + GLfloat t[16]; + identity(t); + + // Extract and invert the translation part 't'. The inverse of a + // translation matrix can be calculated by negating the translation + // coordinates. + t[12] = -m[12]; t[13] = -m[13]; t[14] = -m[14]; + + // Invert the rotation part 'r'. The inverse of a rotation matrix is + // equal to its transpose. + m[12] = m[13] = m[14] = 0; + transpose(m); + + // inv(m) = inv(r) * inv(t) + multiply(m, t); +} + +/** + * Calculate a perspective projection transformation. + * + * @param m the matrix to save the transformation in + * @param fovy the field of view in the y direction + * @param aspect the view aspect ratio + * @param zNear the near clipping plane + * @param zFar the far clipping plane + */ +void perspective(GLfloat *m, GLfloat fovy, GLfloat aspect, GLfloat zNear, GLfloat zFar) +{ + GLfloat tmp[16]; + double sine, cosine, cotangent, deltaZ; + GLfloat radians = fovy / 2 * M_PI / 180; + identity(tmp); + + deltaZ = zFar - zNear; + sincos(radians, &sine, &cosine); + + if ((deltaZ == 0) || (sine == 0) || (aspect == 0)) + return; + + cotangent = cosine / sine; + + tmp[0] = cotangent / aspect; + tmp[5] = cotangent; + tmp[10] = -(zFar + zNear) / deltaZ; + tmp[11] = -1; + tmp[14] = -2 * zNear * zFar / deltaZ; + tmp[15] = 0; + + memcpy(m, tmp, sizeof(tmp)); +} + +/** + * Draws a gear. + * + * @param gear the gear to draw + * @param transform the current transformation matrix + * @param x the x position to draw the gear at + * @param y the y position to draw the gear at + * @param angle the rotation angle of the gear + * @param color the color of the gear + */ +static void +draw_gear(GtkGears *self, + struct gear *gear, + GLuint gear_vbo, + GLfloat *transform, + GLfloat x, + GLfloat y, + GLfloat angle, + const GLfloat color[4]) +{ + GtkGearsPrivate *priv = gtk_gears_get_instance_private (self); + GLfloat model_view[16]; + GLfloat normal_matrix[16]; + GLfloat model_view_projection[16]; + int n; + + /* Translate and rotate the gear */ + memcpy(model_view, transform, sizeof (model_view)); + translate(model_view, x, y, 0); + rotate(model_view, 2 * G_PI * angle / 360.0, 0, 0, 1); + + /* Create and set the ModelViewProjectionMatrix */ + memcpy(model_view_projection, priv->ProjectionMatrix, sizeof(model_view_projection)); + multiply(model_view_projection, model_view); + + glUniformMatrix4fv(priv->ModelViewProjectionMatrix_location, 1, GL_FALSE, + model_view_projection); + + /* + * Create and set the NormalMatrix. It's the inverse transpose of the + * ModelView matrix. + */ + memcpy(normal_matrix, model_view, sizeof (normal_matrix)); + invert(normal_matrix); + transpose(normal_matrix); + glUniformMatrix4fv(priv->NormalMatrix_location, 1, GL_FALSE, normal_matrix); + + /* Set the gear color */ + glUniform4fv(priv->MaterialColor_location, 1, color); + + /* Set the vertex buffer object to use */ + glBindBuffer(GL_ARRAY_BUFFER, gear_vbo); + + /* Set up the position of the attributes in the vertex buffer object */ + glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 6 * sizeof(GLfloat), NULL); + glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 6 * sizeof(GLfloat), (GLfloat *) 0 + 3); + + /* Enable the attributes */ + glEnableVertexAttribArray(0); + glEnableVertexAttribArray(1); + + /* Draw the triangle strips that comprise the gear */ + for (n = 0; n < gear->nstrips; n++) { + glDrawArrays(GL_TRIANGLE_STRIP, gear->strips[n].first, gear->strips[n].count); + } + + /* Disable the attributes */ + glDisableVertexAttribArray(1); + glDisableVertexAttribArray(0); +} + +/* new window size or exposure */ +static void +gtk_gears_reshape (GtkGLArea *area, int width, int height) +{ + GtkGearsPrivate *priv = gtk_gears_get_instance_private ((GtkGears *) area); + + /* Update the projection matrix */ + perspective (priv->ProjectionMatrix, 60.0, width / (float)height, 1.0, 1024.0); + + /* Set the viewport */ + glViewport (0, 0, (GLint) width, (GLint) height); +} + +static gboolean +gtk_gears_render (GtkGLArea *area, + GdkGLContext *context) +{ + static const GLfloat red[4] = { 0.8, 0.1, 0.0, 1.0 }; + static const GLfloat green[4] = { 0.0, 0.8, 0.2, 1.0 }; + static const GLfloat blue[4] = { 0.2, 0.2, 1.0, 1.0 }; + + GtkGears *self = GTK_GEARS (area); + GtkGearsPrivate *priv = gtk_gears_get_instance_private (self); + GLfloat transform[16]; + + identity (transform); + + glClearColor (0.0, 0.0, 0.0, 0.0); + glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); + + /* Translate and rotate the view */ + translate (transform, 0, 0, -20); + rotate (transform, 2 * G_PI * priv->view_rot[0] / 360.0, 1, 0, 0); + rotate (transform, 2 * G_PI * priv->view_rot[1] / 360.0, 0, 1, 0); + rotate (transform, 2 * G_PI * priv->view_rot[2] / 360.0, 0, 0, 1); + + /* Draw the gears */ + draw_gear (self, priv->gear1, priv->gear_vbo[0], transform, -3.0, -2.0, priv->angle, red); + draw_gear (self, priv->gear2, priv->gear_vbo[1], transform, 3.1, -2.0, -2 * priv->angle - 9.0, green); + draw_gear (self, priv->gear3, priv->gear_vbo[2], transform, -3.1, 4.2, -2 * priv->angle - 25.0, blue); + + return TRUE; +} + +static const char vertex_shader_gl[] = +"#version 150\n" +"\n" +"in vec3 position;\n" +"in vec3 normal;\n" +"\n" +"uniform mat4 ModelViewProjectionMatrix;\n" +"uniform mat4 NormalMatrix;\n" +"uniform vec4 LightSourcePosition;\n" +"uniform vec4 MaterialColor;\n" +"\n" +"smooth out vec4 Color;\n" +"\n" +"void main(void)\n" +"{\n" +" // Transform the normal to eye coordinates\n" +" vec3 N = normalize(vec3(NormalMatrix * vec4(normal, 1.0)));\n" +"\n" +" // The LightSourcePosition is actually its direction for directional light\n" +" vec3 L = normalize(LightSourcePosition.xyz);\n" +"\n" +" // Multiply the diffuse value by the vertex color (which is fixed in this case)\n" +" // to get the actual color that we will use to draw this vertex with\n" +" float diffuse = max(dot(N, L), 0.0);\n" +" Color = diffuse * MaterialColor;\n" +"\n" +" // Transform the position to clip coordinates\n" +" gl_Position = ModelViewProjectionMatrix * vec4(position, 1.0);\n" +"}"; + +static const char fragment_shader_gl[] = +"#version 150\n" +"\n" +"smooth in vec4 Color;\n" +"\n" +"void main(void)\n" +"{\n" +" gl_FragColor = Color;\n" +"}"; + +static const char vertex_shader_gles[] = +"attribute vec3 position;\n" +"attribute vec3 normal;\n" +"\n" +"uniform mat4 ModelViewProjectionMatrix;\n" +"uniform mat4 NormalMatrix;\n" +"uniform vec4 LightSourcePosition;\n" +"uniform vec4 MaterialColor;\n" +"\n" +"varying vec4 Color;\n" +"\n" +"void main(void)\n" +"{\n" +" // Transform the normal to eye coordinates\n" +" vec3 N = normalize(vec3(NormalMatrix * vec4(normal, 1.0)));\n" +"\n" +" // The LightSourcePosition is actually its direction for directional light\n" +" vec3 L = normalize(LightSourcePosition.xyz);\n" +"\n" +" // Multiply the diffuse value by the vertex color (which is fixed in this case)\n" +" // to get the actual color that we will use to draw this vertex with\n" +" float diffuse = max(dot(N, L), 0.0);\n" +" Color = diffuse * MaterialColor;\n" +"\n" +" // Transform the position to clip coordinates\n" +" gl_Position = ModelViewProjectionMatrix * vec4(position, 1.0);\n" +"}"; + +static const char fragment_shader_gles[] = +"precision mediump float;\n" +"varying vec4 Color;\n" +"\n" +"void main(void)\n" +"{\n" +" gl_FragColor = Color;\n" +"}"; + +static void +gtk_gears_realize (GtkWidget *widget) +{ + GtkGLArea *glarea = GTK_GL_AREA (widget); + GtkGears *gears = GTK_GEARS (widget); + GtkGearsPrivate *priv = gtk_gears_get_instance_private (gears); + GdkGLContext *context; + GLuint vao, v, f, program; + const char *p; + char msg[512]; + + GTK_WIDGET_CLASS (gtk_gears_parent_class)->realize (widget); + + gtk_gl_area_make_current (glarea); + if (gtk_gl_area_get_error (glarea) != NULL) + return; + + context = gtk_gl_area_get_context (glarea); + + glEnable (GL_CULL_FACE); + glEnable (GL_DEPTH_TEST); + + /* Create the VAO */ + glGenVertexArrays (1, &vao); + glBindVertexArray (vao); + priv->vao = vao; + + /* Compile the vertex shader */ + if (gdk_gl_context_get_use_es (context)) + p = vertex_shader_gles; + else + p = vertex_shader_gl; + v = glCreateShader(GL_VERTEX_SHADER); + glShaderSource(v, 1, &p, NULL); + glCompileShader(v); + glGetShaderInfoLog(v, sizeof msg, NULL, msg); + g_print ("vertex shader info: %s\n", msg); + + /* Compile the fragment shader */ + if (gdk_gl_context_get_use_es (context)) + p = fragment_shader_gles; + else + p = fragment_shader_gl; + f = glCreateShader(GL_FRAGMENT_SHADER); + glShaderSource(f, 1, &p, NULL); + glCompileShader(f); + glGetShaderInfoLog(f, sizeof msg, NULL, msg); + g_print ("fragment shader info: %s\n", msg); + + /* Create and link the shader program */ + program = glCreateProgram(); + glAttachShader(program, v); + glAttachShader(program, f); + glBindAttribLocation(program, 0, "position"); + glBindAttribLocation(program, 1, "normal"); + + glLinkProgram(program); + glGetProgramInfoLog(program, sizeof msg, NULL, msg); + g_print ("program info: %s\n", msg); + glDeleteShader (v); + glDeleteShader (f); + + /* Enable the shaders */ + glUseProgram(program); + priv->program = program; + + /* Get the locations of the uniforms so we can access them */ + priv->ModelViewProjectionMatrix_location = glGetUniformLocation(program, "ModelViewProjectionMatrix"); + priv->NormalMatrix_location = glGetUniformLocation(program, "NormalMatrix"); + priv->LightSourcePosition_location = glGetUniformLocation(program, "LightSourcePosition"); + priv->MaterialColor_location = glGetUniformLocation(program, "MaterialColor"); + + /* Set the LightSourcePosition uniform which is constant throught the program */ + glUniform4fv(priv->LightSourcePosition_location, 1, priv->LightSourcePosition); + + /* make the gears */ + priv->gear1 = create_gear(1.0, 4.0, 1.0, 20, 0.7); + + /* Store the vertices in a vertex buffer object (VBO) */ + glGenBuffers (1, &(priv->gear_vbo[0])); + glBindBuffer (GL_ARRAY_BUFFER, priv->gear_vbo[0]); + glBufferData (GL_ARRAY_BUFFER, + priv->gear1->nvertices * sizeof(GearVertex), + priv->gear1->vertices, + GL_STATIC_DRAW); + + priv->gear2 = create_gear(0.5, 2.0, 2.0, 10, 0.7); + glGenBuffers (1, &(priv->gear_vbo[1])); + glBindBuffer (GL_ARRAY_BUFFER, priv->gear_vbo[1]); + glBufferData (GL_ARRAY_BUFFER, + priv->gear2->nvertices * sizeof(GearVertex), + priv->gear2->vertices, + GL_STATIC_DRAW); + + priv->gear3 = create_gear(1.3, 2.0, 0.5, 10, 0.7); + glGenBuffers (1, &(priv->gear_vbo[2])); + glBindBuffer (GL_ARRAY_BUFFER, priv->gear_vbo[2]); + glBufferData (GL_ARRAY_BUFFER, + priv->gear3->nvertices * sizeof(GearVertex), + priv->gear3->vertices, + GL_STATIC_DRAW); +} + +static void +gtk_gears_unrealize (GtkWidget *widget) +{ + GtkGLArea *glarea = GTK_GL_AREA (widget); + GtkGearsPrivate *priv = gtk_gears_get_instance_private ((GtkGears *) widget); + + gtk_gl_area_make_current (glarea); + if (gtk_gl_area_get_error (glarea) != NULL) + return; + + /* Release the resources associated with OpenGL */ + if (priv->gear_vbo[0] != 0) + glDeleteBuffers (1, &(priv->gear_vbo[0])); + + if (priv->gear_vbo[1] != 0) + glDeleteBuffers (1, &(priv->gear_vbo[1])); + + if (priv->gear_vbo[2] != 0) + glDeleteBuffers (1, &(priv->gear_vbo[2])); + + if (priv->vao != 0) + glDeleteVertexArrays (1, &priv->vao); + + if (priv->program != 0) + glDeleteProgram (priv->program); + + priv->ModelViewProjectionMatrix_location = 0; + priv->NormalMatrix_location = 0; + priv->LightSourcePosition_location = 0; + priv->MaterialColor_location = 0; + + GTK_WIDGET_CLASS (gtk_gears_parent_class)->unrealize (widget); +} + +static gboolean +gtk_gears_tick (GtkWidget *widget, + GdkFrameClock *frame_clock, + gpointer user_data) +{ + GtkGears *gears = GTK_GEARS (widget); + GtkGearsPrivate *priv = gtk_gears_get_instance_private (gears); + GdkFrameTimings *timings, *previous_timings; + gint64 previous_frame_time = 0; + gint64 frame_time; + gint64 history_start, history_len; + gint64 frame; + char *s; + + frame = gdk_frame_clock_get_frame_counter (frame_clock); + frame_time = gdk_frame_clock_get_frame_time (frame_clock); + + if (priv->first_frame_time == 0) + { + /* No need for changes on first frame */ + priv->first_frame_time = frame_time; + if (priv->fps_label) + gtk_label_set_label (priv->fps_label, "FPS: ---"); + return G_SOURCE_CONTINUE; + } + + /* glxgears advances 70 degrees per second, so do the same */ + + priv->angle = fmod ((frame_time - priv->first_frame_time) / (double)G_USEC_PER_SEC * 70.0, 360.0); + + gtk_widget_queue_draw (widget); + + history_start = gdk_frame_clock_get_history_start (frame_clock); + + if (priv->fps_label && frame % 60 == 0) + { + history_len = frame - history_start; + if (history_len > 0) + { + previous_timings = gdk_frame_clock_get_timings (frame_clock, frame - history_len); + previous_frame_time = gdk_frame_timings_get_frame_time (previous_timings); + + s = g_strdup_printf ("FPS: %-4.1f", (G_USEC_PER_SEC * history_len) / (double)(frame_time - previous_frame_time)); + gtk_label_set_label (priv->fps_label, s); + g_free (s); + } + } + + timings = gdk_frame_clock_get_current_timings (frame_clock); + previous_timings = gdk_frame_clock_get_timings (frame_clock, + gdk_frame_timings_get_frame_counter (timings) - 1); + if (previous_timings != NULL) + previous_frame_time = gdk_frame_timings_get_frame_time (previous_timings); + + return G_SOURCE_CONTINUE; +} + +void +gtk_gears_set_axis (GtkGears *gears, int axis, double value) +{ + GtkGearsPrivate *priv = gtk_gears_get_instance_private (gears); + + if (axis < 0 || axis >= GTK_GEARS_N_AXIS) + return; + + priv->view_rot[axis] = value; + + gtk_widget_queue_draw (GTK_WIDGET (gears)); +} + +double +gtk_gears_get_axis (GtkGears *gears, int axis) +{ + GtkGearsPrivate *priv = gtk_gears_get_instance_private (gears); + + if (axis < 0 || axis >= GTK_GEARS_N_AXIS) + return 0.0; + + return priv->view_rot[axis]; +} + +void +gtk_gears_set_fps_label (GtkGears *gears, GtkLabel *label) +{ + GtkGearsPrivate *priv = gtk_gears_get_instance_private (gears); + + if (label) + g_object_ref (label); + + g_clear_object (&priv->fps_label); + + priv->fps_label = label; +} diff --git a/demos/gtk-demo/gtkgears.h b/demos/gtk-demo/gtkgears.h new file mode 100644 index 0000000000..0109723c14 --- /dev/null +++ b/demos/gtk-demo/gtkgears.h @@ -0,0 +1,48 @@ +#ifndef __GTK_GEARS_H__ +#define __GTK_GEARS_H__ + +#include + +G_BEGIN_DECLS + +enum { + GTK_GEARS_X_AXIS, + GTK_GEARS_Y_AXIS, + GTK_GEARS_Z_AXIS, + + GTK_GEARS_N_AXIS +}; + +#define GTK_TYPE_GEARS (gtk_gears_get_type ()) +#define GTK_GEARS(inst) (G_TYPE_CHECK_INSTANCE_CAST ((inst), \ + GTK_TYPE_GEARS, \ + GtkGears)) +#define GTK_IS_GEARS(inst) (G_TYPE_CHECK_INSTANCE_TYPE ((inst), \ + GTK_TYPE_GEARS)) + +typedef struct _GtkGears GtkGears; +typedef struct _GtkGearsClass GtkGearsClass; + +struct _GtkGears { + GtkGLArea parent; +}; + +struct _GtkGearsClass { + GtkGLAreaClass parent_class; +}; + +GType gtk_gears_get_type (void) G_GNUC_CONST; + +GtkWidget *gtk_gears_new (void); +void gtk_gears_set_axis (GtkGears *gears, + int axis, + double value); +double gtk_gears_get_axis (GtkGears *gears, + int axis); +void gtk_gears_set_fps_label (GtkGears *gears, + GtkLabel *label); + + +G_END_DECLS + +#endif /* __GTK_GEARS_H__ */ diff --git a/demos/gtk-demo/meson.build b/demos/gtk-demo/meson.build index f4c3613215..ed2e58c5df 100644 --- a/demos/gtk-demo/meson.build +++ b/demos/gtk-demo/meson.build @@ -94,7 +94,9 @@ gtkdemo_resources = gnome.compile_resources('gtkdemo_resources', source_dir: '.') executable('gtk4-demo', - 'main.c', 'gtkfishbowl.c', 'fontplane.c', 'script-names.c', 'language-names.c', demos, demos_h, gtkdemo_resources, + 'main.c', 'gtkfishbowl.c', 'fontplane.c', 'script-names.c', 'language-names.c', + 'gtkgears.c', + demos, demos_h, gtkdemo_resources, c_args: gtkdemo_args, dependencies: gtkdemo_deps, include_directories: confinc, diff --git a/demos/gtk-demo/widgetbowl.c b/demos/gtk-demo/widgetbowl.c index 1ac2139cbe..aadee03610 100644 --- a/demos/gtk-demo/widgetbowl.c +++ b/demos/gtk-demo/widgetbowl.c @@ -8,6 +8,7 @@ #include #include "gtkfishbowl.h" +#include "gtkgears.h" const char *const css = ".blurred-button {" @@ -80,6 +81,16 @@ create_label (void) return w; } +static GtkWidget * +create_gears (void) +{ + GtkWidget *w = gtk_gears_new (); + + gtk_widget_set_size_request (w, 100, 100); + + return w; +} + static const struct { const char *name; GtkWidget * (*create_func) (void); @@ -91,6 +102,7 @@ static const struct { { "Label" , create_label }, { "Spinner" , create_spinner }, { "Spinbutton", create_spinbutton }, + { "Gears", create_gears }, }; static int selected_widget_type = -1; -- 2.30.2