From 0047a1f6045c34a0d488df9ec85ad0ab0f9ac550 Mon Sep 17 00:00:00 2001 From: Robert Bragg Date: Thu, 19 Apr 2012 14:28:50 +0100 Subject: [PATCH] Adds a cogl-gles2-gears example This adds an example of using libcogl-gles2 as a way to port existing GLES 2.0 based code. This is a port of es2gears in the Mesa demos repo. Reviewed-by: Neil Roberts (cherry picked from commit fcb947178858e9d675c5f76e50510282c6b0bf8d) --- examples/Makefile.am | 6 +- examples/cogl-gles2-gears.c | 808 ++++++++++++++++++++++++++++++++++++ 2 files changed, 813 insertions(+), 1 deletion(-) create mode 100644 examples/cogl-gles2-gears.c diff --git a/examples/Makefile.am b/examples/Makefile.am index 7fd76a565..7dedee41d 100644 --- a/examples/Makefile.am +++ b/examples/Makefile.am @@ -24,7 +24,7 @@ cogl_info_SOURCES = cogl-info.c cogl_info_LDADD = $(common_ldadd) if USE_GLIB -programs += cogl-hello cogl-msaa cogl-gles2-context +programs += cogl-hello cogl-msaa cogl-gles2-context cogl-gles2-gears examples_datadir = $(pkgdatadir)/examples-data examples_data_DATA = @@ -66,6 +66,10 @@ endif cogl_gles2_context_SOURCES = cogl-gles2-context.c cogl_gles2_context_LDADD = $(common_ldadd) +cogl_gles2_gears_SOURCES = cogl-gles2-gears.c +cogl_gles2_gears_CFLAGS = -I$(top_srcdir)/cogl-gles2 $(AM_CFLAGS) +cogl_gles2_gears_LDADD = $(common_ldadd) $(top_builddir)/cogl-gles2/libcogl-gles2.la + endif #USE_GLIB if INSTALL_EXAMPLES diff --git a/examples/cogl-gles2-gears.c b/examples/cogl-gles2-gears.c new file mode 100644 index 000000000..f77e550fd --- /dev/null +++ b/examples/cogl-gles2-gears.c @@ -0,0 +1,808 @@ +/* + * 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 + */ + +#define GL_GLEXT_PROTOTYPES + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define STRIPS_PER_TOOTH 7 +#define VERTICES_PER_TOOTH 34 +#define GEAR_VERTEX_STRIDE 6 + +typedef struct _Data +{ + CoglContext *ctx; + CoglFramebuffer *fb; + + CoglGLES2Context *gles2_ctx; + + GTimer *timer; + int frames; + double last_elapsed; +} Data; + + +/** + * 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; + /** The Vertex Buffer Object holding the vertices in the graphics card */ + GLuint vbo; +}; + +/** The view rotation [x, y, z] */ +static GLfloat view_rot[3] = { 20.0, 30.0, 0.0 }; +/** The gears */ +static struct gear *gear1, *gear2, *gear3; +/** The current gear rotation angle */ +static GLfloat angle = 0.0; +/** The location of the shader uniforms */ +static GLuint ModelViewProjectionMatrix_location, + NormalMatrix_location, + LightSourcePosition_location, + MaterialColor_location; +/** The projection matrix */ +static GLfloat ProjectionMatrix[16]; +/** The direction of the directional light for the scene */ +static const GLfloat LightSourcePosition[4] = { 5.0, 5.0, 10.0, 1.0}; + +/** + * 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; +} + +/** + * 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 = malloc (sizeof *gear); + if (gear == NULL) + return NULL; + + /* 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 = calloc (gear->nstrips, sizeof (*gear->strips)); + + /* Allocate memory for the vertices */ + gear->vertices = calloc (VERTICES_PER_TOOTH * teeth, sizeof(*gear->vertices)); + v = gear->vertices; + + for (i = 0; i < teeth; i++) { + /* Calculate needed sin/cos for varius angles */ + sincos (i * 2.0 * M_PI / teeth, &s[0], &c[0]); + sincos (i * 2.0 * M_PI / teeth + da, &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]); + + /* A set of macros for making the creation of the gears easier */ +#define GEAR_POINT(r, da) { (r) * c[(da)], (r) * s[(da)] } +#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] = { + GEAR_POINT (r2, 1), // 0 + GEAR_POINT (r2, 2), // 1 + GEAR_POINT (r1, 0), // 2 + GEAR_POINT (r1, 3), // 3 + GEAR_POINT (r0, 0), // 4 + GEAR_POINT (r1, 4), // 5 + GEAR_POINT (r0, 4), // 6 + }; + + /* 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); + + /* Store the vertices in a vertex buffer object (VBO) */ + glGenBuffers (1, &gear->vbo); + glBindBuffer (GL_ARRAY_BUFFER, gear->vbo); + glBufferData (GL_ARRAY_BUFFER, gear->nvertices * sizeof(GearVertex), + gear->vertices, GL_STATIC_DRAW); + + 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, c; + + sincos (angle, &s, &c); + + { + 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 + */ +static 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 (struct gear *gear, GLfloat *transform, + GLfloat x, GLfloat y, GLfloat angle, const GLfloat color[4]) +{ + 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 * M_PI * angle / 360.0, 0, 0, 1); + + /* Create and set the ModelViewProjectionMatrix */ + memcpy (model_view_projection, + ProjectionMatrix, + sizeof(model_view_projection)); + multiply (model_view_projection, model_view); + + glUniformMatrix4fv (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 (NormalMatrix_location, 1, GL_FALSE, normal_matrix); + + /* Set the gear color */ + glUniform4fv (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); +} + +/** + * Draws the gears. + */ +static void +gears_draw(void) +{ + const static GLfloat red[4] = { 0.8, 0.1, 0.0, 1.0 }; + const static GLfloat green[4] = { 0.0, 0.8, 0.2, 1.0 }; + const static GLfloat blue[4] = { 0.2, 0.2, 1.0, 1.0 }; + 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 * M_PI * view_rot[0] / 360.0, 1, 0, 0); + rotate (transform, 2 * M_PI * view_rot[1] / 360.0, 0, 1, 0); + rotate (transform, 2 * M_PI * view_rot[2] / 360.0, 0, 0, 1); + + /* Draw the gears */ + draw_gear (gear1, transform, -3.0, -2.0, angle, red); + draw_gear (gear2, transform, 3.1, -2.0, -2 * angle - 9.0, green); + draw_gear (gear3, transform, -3.1, 4.2, -2 * angle - 25.0, blue); +} + +static gboolean +paint_cb (void *user_data) +{ + Data *data = user_data; + double elapsed = g_timer_elapsed (data->timer, NULL); + double dt = elapsed - data->last_elapsed; + GError *error = NULL; + + /* Draw scene with GLES2 */ + if (!cogl_push_gles2_context (data->ctx, + data->gles2_ctx, + data->fb, + data->fb, + &error)) + { + g_error ("Failed to push gles2 context: %s\n", error->message); + } + + gears_draw (); + + cogl_pop_gles2_context (data->ctx); + + cogl_onscreen_swap_buffers (COGL_ONSCREEN (data->fb)); + + /* advance rotation for next frame */ + angle += 70.0 * dt; /* 70 degrees per second */ + if (angle > 3600.0) + angle -= 3600.0; + + data->frames++; + + if (elapsed > 5.0) { + GLfloat fps = data->frames / elapsed; + printf ("%d frames in %3.1f seconds = %6.3f FPS\n", + data->frames, elapsed, fps); + g_timer_reset (data->timer); + data->last_elapsed = 0; + data->frames = 0; + }else + data->last_elapsed = elapsed; + + /* If the driver can deliver swap complete events then we can remove + * the idle paint callback until we next get a swap complete event + * otherwise we keep the idle paint callback installed and simply + * paint as fast as the driver will allow... */ + if (cogl_has_feature (data->ctx, COGL_FEATURE_ID_SWAP_BUFFERS_EVENT)) + return FALSE; /* remove the callback */ + else + return TRUE; +} + +static void +swap_complete_cb (CoglFramebuffer *framebuffer, void *user_data) +{ + g_idle_add (paint_cb, user_data); +} + +/** + * Handles a new window size or exposure. + * + * @param width the window width + * @param height the window height + */ +static void +gears_reshape (int width, int height) +{ + /* Update the projection matrix */ + perspective (ProjectionMatrix, 60.0, width / (float)height, 1.0, 1024.0); + + /* Set the viewport */ + glViewport (0, 0, (GLint) width, (GLint) height); +} + +#if 0 +/** + * Handles special eglut events. + * + * @param special the event to handle. + */ +static void +gears_special(int special) +{ + switch (special) { + case EGLUT_KEY_LEFT: + view_rot[1] += 5.0; + break; + case EGLUT_KEY_RIGHT: + view_rot[1] -= 5.0; + break; + case EGLUT_KEY_UP: + view_rot[0] += 5.0; + break; + case EGLUT_KEY_DOWN: + view_rot[0] -= 5.0; + break; + } +} +#endif + +static const char vertex_shader[] = + "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[] = + "precision mediump float;\n" + "varying vec4 Color;\n" + "\n" + "void main(void)\n" + "{\n" + " gl_FragColor = Color;\n" + "}"; + +static void +gears_init(void) +{ + GLuint v, f, program; + const char *p; + char msg[512]; + + glEnable (GL_CULL_FACE); + glEnable (GL_DEPTH_TEST); + + /* Compile the vertex shader */ + p = vertex_shader; + v = glCreateShader (GL_VERTEX_SHADER); + glShaderSource (v, 1, &p, NULL); + glCompileShader (v); + glGetShaderInfoLog (v, sizeof msg, NULL, msg); + printf ("vertex shader info: %s\n", msg); + + /* Compile the fragment shader */ + p = fragment_shader; + f = glCreateShader (GL_FRAGMENT_SHADER); + glShaderSource (f, 1, &p, NULL); + glCompileShader (f); + glGetShaderInfoLog (f, sizeof msg, NULL, msg); + printf ("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); + printf ("info: %s\n", msg); + + /* Enable the shaders */ + glUseProgram (program); + + /* Get the locations of the uniforms so we can access them */ + ModelViewProjectionMatrix_location = + glGetUniformLocation (program, "ModelViewProjectionMatrix"); + NormalMatrix_location = + glGetUniformLocation (program, "NormalMatrix"); + LightSourcePosition_location = + glGetUniformLocation (program, "LightSourcePosition"); + MaterialColor_location = + glGetUniformLocation (program, "MaterialColor"); + + /* Set the LightSourcePosition uniform which is constant throughout + * the program */ + glUniform4fv (LightSourcePosition_location, 1, LightSourcePosition); + + /* make the gears */ + gear1 = create_gear (1.0, 4.0, 1.0, 20, 0.7); + gear2 = create_gear (0.5, 2.0, 2.0, 10, 0.7); + gear3 = create_gear (1.3, 2.0, 0.5, 10, 0.7); +} + +int +main (int argc, char **argv) +{ + Data data; + CoglOnscreen *onscreen; + GError *error = NULL; + GSource *cogl_source; + GMainLoop *loop; + + data.ctx = cogl_context_new (NULL, NULL); + + onscreen = cogl_onscreen_new (data.ctx, 300, 300); + cogl_onscreen_show (onscreen); + data.fb = COGL_FRAMEBUFFER (onscreen); + + data.gles2_ctx = cogl_gles2_context_new (data.ctx, &error); + if (!data.gles2_ctx) + g_error ("Failed to create GLES2 context: %s\n", error->message); + + /* Draw scene with GLES2 */ + if (!cogl_push_gles2_context (data.ctx, + data.gles2_ctx, + data.fb, + data.fb, + &error)) + { + g_error ("Failed to push gles2 context: %s\n", error->message); + } + + gears_reshape (cogl_framebuffer_get_width (data.fb), + cogl_framebuffer_get_height (data.fb)); + + /* Initialize the gears */ + gears_init(); + + cogl_pop_gles2_context (data.ctx); + + cogl_source = cogl_glib_source_new (data.ctx, G_PRIORITY_DEFAULT); + + g_source_attach (cogl_source, NULL); + + if (cogl_has_feature (data.ctx, COGL_FEATURE_ID_SWAP_BUFFERS_EVENT)) + cogl_onscreen_add_swap_buffers_callback (COGL_ONSCREEN (data.fb), + swap_complete_cb, &data); + + g_idle_add (paint_cb, &data); + + data.timer = g_timer_new (); + data.frames = 0; + data.last_elapsed = 0; + + loop = g_main_loop_new (NULL, TRUE); + g_main_loop_run (loop); + + return 0; +}