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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 <neil@linux.intel.com> (cherry picked from commit fcb947178858e9d675c5f76e50510282c6b0bf8d)
This commit is contained in:
Robert Bragg
parent
10340a5495
commit
0047a1f604
@ -24,7 +24,7 @@ cogl_info_SOURCES = cogl-info.c
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cogl_info_LDADD = $(common_ldadd)
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if USE_GLIB
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programs += cogl-hello cogl-msaa cogl-gles2-context
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programs += cogl-hello cogl-msaa cogl-gles2-context cogl-gles2-gears
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examples_datadir = $(pkgdatadir)/examples-data
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examples_data_DATA =
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@ -66,6 +66,10 @@ endif
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cogl_gles2_context_SOURCES = cogl-gles2-context.c
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cogl_gles2_context_LDADD = $(common_ldadd)
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cogl_gles2_gears_SOURCES = cogl-gles2-gears.c
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cogl_gles2_gears_CFLAGS = -I$(top_srcdir)/cogl-gles2 $(AM_CFLAGS)
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cogl_gles2_gears_LDADD = $(common_ldadd) $(top_builddir)/cogl-gles2/libcogl-gles2.la
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endif #USE_GLIB
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if INSTALL_EXAMPLES
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808
examples/cogl-gles2-gears.c
Normal file
808
examples/cogl-gles2-gears.c
Normal file
@ -0,0 +1,808 @@
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/*
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* Copyright (C) 1999-2001 Brian Paul All Rights Reserved.
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*
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* Permission is hereby granted, free of charge, to any person obtaining a
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* copy of this software and associated documentation files (the "Software"),
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* to deal in the Software without restriction, including without limitation
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* the rights to use, copy, modify, merge, publish, distribute, sublicense,
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* and/or sell copies of the Software, and to permit persons to whom the
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* Software is furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included
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* in all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
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* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
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* AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
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* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
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*/
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/*
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* Ported to GLES2.
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* Kristian Høgsberg <krh@bitplanet.net>
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* May 3, 2010
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*
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* Improve GLES2 port:
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* * Refactor gear drawing.
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* * Use correct normals for surfaces.
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* * Improve shader.
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* * Use perspective projection transformation.
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* * Add FPS count.
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* * Add comments.
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* Alexandros Frantzis <alexandros.frantzis@linaro.org>
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* Jul 13, 2010
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*/
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#define GL_GLEXT_PROTOTYPES
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#include <math.h>
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#include <stdlib.h>
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#include <stdio.h>
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#include <string.h>
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#include <sys/time.h>
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#include <unistd.h>
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#include <GLES2/gl2.h>
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#include <cogl/cogl.h>
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#include <cogl/cogl-gles2.h>
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#include <glib.h>
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#define STRIPS_PER_TOOTH 7
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#define VERTICES_PER_TOOTH 34
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#define GEAR_VERTEX_STRIDE 6
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typedef struct _Data
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{
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CoglContext *ctx;
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CoglFramebuffer *fb;
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CoglGLES2Context *gles2_ctx;
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GTimer *timer;
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int frames;
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double last_elapsed;
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} Data;
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/**
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* Struct describing the vertices in triangle strip
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*/
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struct vertex_strip {
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/** The first vertex in the strip */
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GLint first;
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/** The number of consecutive vertices in the strip after the first */
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GLint count;
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};
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/* Each vertex consist of GEAR_VERTEX_STRIDE GLfloat attributes */
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typedef GLfloat GearVertex[GEAR_VERTEX_STRIDE];
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/**
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* Struct representing a gear.
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*/
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struct gear {
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/** The array of vertices comprising the gear */
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GearVertex *vertices;
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/** The number of vertices comprising the gear */
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int nvertices;
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/** The array of triangle strips comprising the gear */
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struct vertex_strip *strips;
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/** The number of triangle strips comprising the gear */
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int nstrips;
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/** The Vertex Buffer Object holding the vertices in the graphics card */
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GLuint vbo;
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};
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/** The view rotation [x, y, z] */
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static GLfloat view_rot[3] = { 20.0, 30.0, 0.0 };
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/** The gears */
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static struct gear *gear1, *gear2, *gear3;
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/** The current gear rotation angle */
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static GLfloat angle = 0.0;
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/** The location of the shader uniforms */
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static GLuint ModelViewProjectionMatrix_location,
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NormalMatrix_location,
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LightSourcePosition_location,
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MaterialColor_location;
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/** The projection matrix */
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static GLfloat ProjectionMatrix[16];
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/** The direction of the directional light for the scene */
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static const GLfloat LightSourcePosition[4] = { 5.0, 5.0, 10.0, 1.0};
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/**
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* Fills a gear vertex.
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*
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* @param v the vertex to fill
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* @param x the x coordinate
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* @param y the y coordinate
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* @param z the z coortinate
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* @param n pointer to the normal table
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*
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* @return the operation error code
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*/
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static GearVertex *
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vert (GearVertex *v, GLfloat x, GLfloat y, GLfloat z, GLfloat n[3])
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{
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v[0][0] = x;
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v[0][1] = y;
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v[0][2] = z;
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v[0][3] = n[0];
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v[0][4] = n[1];
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v[0][5] = n[2];
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return v + 1;
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}
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/**
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* Create a gear wheel.
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*
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* @param inner_radius radius of hole at center
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* @param outer_radius radius at center of teeth
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* @param width width of gear
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* @param teeth number of teeth
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* @param tooth_depth depth of tooth
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*
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* @return pointer to the constructed struct gear
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*/
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static struct gear *
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create_gear (GLfloat inner_radius, GLfloat outer_radius, GLfloat width,
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GLint teeth, GLfloat tooth_depth)
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{
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GLfloat r0, r1, r2;
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GLfloat da;
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GearVertex *v;
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struct gear *gear;
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double s[5], c[5];
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GLfloat normal[3];
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int cur_strip = 0;
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int i;
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/* Allocate memory for the gear */
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gear = malloc (sizeof *gear);
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if (gear == NULL)
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return NULL;
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/* Calculate the radii used in the gear */
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r0 = inner_radius;
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r1 = outer_radius - tooth_depth / 2.0;
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r2 = outer_radius + tooth_depth / 2.0;
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da = 2.0 * M_PI / teeth / 4.0;
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/* Allocate memory for the triangle strip information */
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gear->nstrips = STRIPS_PER_TOOTH * teeth;
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gear->strips = calloc (gear->nstrips, sizeof (*gear->strips));
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/* Allocate memory for the vertices */
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gear->vertices = calloc (VERTICES_PER_TOOTH * teeth, sizeof(*gear->vertices));
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v = gear->vertices;
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for (i = 0; i < teeth; i++) {
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/* Calculate needed sin/cos for varius angles */
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sincos (i * 2.0 * M_PI / teeth, &s[0], &c[0]);
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sincos (i * 2.0 * M_PI / teeth + da, &s[1], &c[1]);
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sincos (i * 2.0 * M_PI / teeth + da * 2, &s[2], &c[2]);
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sincos (i * 2.0 * M_PI / teeth + da * 3, &s[3], &c[3]);
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sincos (i * 2.0 * M_PI / teeth + da * 4, &s[4], &c[4]);
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/* A set of macros for making the creation of the gears easier */
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#define GEAR_POINT(r, da) { (r) * c[(da)], (r) * s[(da)] }
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#define SET_NORMAL(x, y, z) do { \
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normal[0] = (x); normal[1] = (y); normal[2] = (z); \
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} while(0)
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#define GEAR_VERT(v, point, sign) vert((v), p[(point)].x, p[(point)].y, (sign) * width * 0.5, normal)
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#define START_STRIP do { \
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gear->strips[cur_strip].first = v - gear->vertices; \
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} while(0);
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#define END_STRIP do { \
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int _tmp = (v - gear->vertices); \
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gear->strips[cur_strip].count = _tmp - gear->strips[cur_strip].first; \
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cur_strip++; \
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} while (0)
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#define QUAD_WITH_NORMAL(p1, p2) do { \
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SET_NORMAL((p[(p1)].y - p[(p2)].y), -(p[(p1)].x - p[(p2)].x), 0); \
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v = GEAR_VERT(v, (p1), -1); \
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v = GEAR_VERT(v, (p1), 1); \
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v = GEAR_VERT(v, (p2), -1); \
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v = GEAR_VERT(v, (p2), 1); \
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} while(0)
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{
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struct point {
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GLfloat x;
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GLfloat y;
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};
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/* Create the 7 points (only x,y coords) used to draw a tooth */
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struct point p[7] = {
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GEAR_POINT (r2, 1), // 0
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GEAR_POINT (r2, 2), // 1
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GEAR_POINT (r1, 0), // 2
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GEAR_POINT (r1, 3), // 3
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GEAR_POINT (r0, 0), // 4
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GEAR_POINT (r1, 4), // 5
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GEAR_POINT (r0, 4), // 6
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};
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/* Front face */
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START_STRIP;
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SET_NORMAL (0, 0, 1.0);
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v = GEAR_VERT (v, 0, +1);
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v = GEAR_VERT (v, 1, +1);
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v = GEAR_VERT (v, 2, +1);
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v = GEAR_VERT (v, 3, +1);
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v = GEAR_VERT (v, 4, +1);
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v = GEAR_VERT (v, 5, +1);
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v = GEAR_VERT (v, 6, +1);
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END_STRIP;
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/* Inner face */
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START_STRIP;
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QUAD_WITH_NORMAL (4, 6);
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END_STRIP;
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/* Back face */
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START_STRIP;
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SET_NORMAL (0, 0, -1.0);
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v = GEAR_VERT (v, 6, -1);
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v = GEAR_VERT (v, 5, -1);
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v = GEAR_VERT (v, 4, -1);
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v = GEAR_VERT (v, 3, -1);
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v = GEAR_VERT (v, 2, -1);
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v = GEAR_VERT (v, 1, -1);
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v = GEAR_VERT (v, 0, -1);
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END_STRIP;
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/* Outer face */
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START_STRIP;
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QUAD_WITH_NORMAL (0, 2);
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END_STRIP;
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START_STRIP;
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QUAD_WITH_NORMAL (1, 0);
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END_STRIP;
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START_STRIP;
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QUAD_WITH_NORMAL (3, 1);
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END_STRIP;
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START_STRIP;
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QUAD_WITH_NORMAL (5, 3);
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END_STRIP;
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}
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}
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gear->nvertices = (v - gear->vertices);
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/* Store the vertices in a vertex buffer object (VBO) */
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glGenBuffers (1, &gear->vbo);
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glBindBuffer (GL_ARRAY_BUFFER, gear->vbo);
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glBufferData (GL_ARRAY_BUFFER, gear->nvertices * sizeof(GearVertex),
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gear->vertices, GL_STATIC_DRAW);
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return gear;
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}
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/**
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* Multiplies two 4x4 matrices.
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*
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* The result is stored in matrix m.
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*
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* @param m the first matrix to multiply
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* @param n the second matrix to multiply
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*/
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static void
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multiply (GLfloat *m, const GLfloat *n)
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{
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GLfloat tmp[16];
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const GLfloat *row, *column;
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div_t d;
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int i, j;
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for (i = 0; i < 16; i++) {
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tmp[i] = 0;
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d = div(i, 4);
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row = n + d.quot * 4;
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column = m + d.rem;
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for (j = 0; j < 4; j++)
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tmp[i] += row[j] * column[j * 4];
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}
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memcpy (m, &tmp, sizeof tmp);
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}
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/**
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* Rotates a 4x4 matrix.
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*
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* @param[in,out] m the matrix to rotate
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* @param angle the angle to rotate
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* @param x the x component of the direction to rotate to
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* @param y the y component of the direction to rotate to
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* @param z the z component of the direction to rotate to
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*/
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static void
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rotate (GLfloat *m, GLfloat angle, GLfloat x, GLfloat y, GLfloat z)
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{
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double s, c;
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sincos (angle, &s, &c);
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{
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GLfloat r[16] = {
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x * x * (1 - c) + c, y * x * (1 - c) + z * s, x * z * (1 - c) - y * s, 0,
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x * y * (1 - c) - z * s, y * y * (1 - c) + c, y * z * (1 - c) + x * s, 0,
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x * z * (1 - c) + y * s, y * z * (1 - c) - x * s, z * z * (1 - c) + c, 0,
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0, 0, 0, 1
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};
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multiply (m, r);
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}
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}
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/**
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* Translates a 4x4 matrix.
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*
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* @param[in,out] m the matrix to translate
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* @param x the x component of the direction to translate to
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* @param y the y component of the direction to translate to
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* @param z the z component of the direction to translate to
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*/
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static void
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translate(GLfloat *m, GLfloat x, GLfloat y, GLfloat z)
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{
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GLfloat t[16] = { 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, x, y, z, 1 };
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multiply (m, t);
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}
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/**
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* Creates an identity 4x4 matrix.
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*
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* @param m the matrix make an identity matrix
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*/
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static void
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identity (GLfloat *m)
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{
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GLfloat t[16] = {
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1.0, 0.0, 0.0, 0.0,
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0.0, 1.0, 0.0, 0.0,
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0.0, 0.0, 1.0, 0.0,
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0.0, 0.0, 0.0, 1.0,
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};
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memcpy (m, t, sizeof(t));
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}
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/**
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* Transposes a 4x4 matrix.
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*
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* @param m the matrix to transpose
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*/
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static void
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transpose (GLfloat *m)
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{
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GLfloat t[16] = {
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m[0], m[4], m[8], m[12],
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m[1], m[5], m[9], m[13],
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m[2], m[6], m[10], m[14],
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m[3], m[7], m[11], m[15]};
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memcpy (m, t, sizeof(t));
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}
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/**
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* Inverts a 4x4 matrix.
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*
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* This function can currently handle only pure translation-rotation matrices.
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* Read http://www.gamedev.net/community/forums/topic.asp?topic_id=425118
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* for an explanation.
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*/
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static void
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invert (GLfloat *m)
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{
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GLfloat t[16];
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identity (t);
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// Extract and invert the translation part 't'. The inverse of a
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// translation matrix can be calculated by negating the translation
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// coordinates.
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t[12] = -m[12]; t[13] = -m[13]; t[14] = -m[14];
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// Invert the rotation part 'r'. The inverse of a rotation matrix is
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// equal to its transpose.
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m[12] = m[13] = m[14] = 0;
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transpose (m);
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// inv (m) = inv (r) * inv (t)
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multiply (m, t);
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}
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/**
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* Calculate a perspective projection transformation.
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*
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* @param m the matrix to save the transformation in
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* @param fovy the field of view in the y direction
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* @param aspect the view aspect ratio
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* @param zNear the near clipping plane
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* @param zFar the far clipping plane
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*/
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static void
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perspective (GLfloat *m, GLfloat fovy, GLfloat aspect, GLfloat zNear, GLfloat zFar)
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{
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GLfloat tmp[16];
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double sine, cosine, cotangent, deltaZ;
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GLfloat radians = fovy / 2 * M_PI / 180;
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identity (tmp);
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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;
|
||||
}
|
||||
Loading…
Reference in New Issue
Block a user