--- /dev/null
+/*
+ * 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 <krh@bitplanet.net>
+ * May 3, 2010
+ */
+
+/*
+ * Command line options:
+ * -info print GL implementation information
+ *
+ */
+
+
+#define GL_GLEXT_PROTOTYPES
+#define EGL_EGLEXT_PROTOTYPES
+
+#include <math.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/time.h>
+#include <unistd.h>
+#include <GLES2/gl2.h>
+#include <EGL/egl.h>
+#include <EGL/eglext.h>
+#include "eglut.h"
+
+struct gear {
+ GLfloat *vertices;
+ GLuint vbo;
+ int count;
+};
+
+static GLfloat view_rotx = 20.0, view_roty = 30.0, view_rotz = 0.0;
+static struct gear *gear1, *gear2, *gear3;
+static GLfloat angle = 0.0;
+static GLuint proj_location, light_location, color_location;
+static GLfloat proj[16];
+
+static GLfloat *
+vert(GLfloat *p, GLfloat x, GLfloat y, GLfloat z, GLfloat *n)
+{
+ p[0] = x;
+ p[1] = y;
+ p[2] = z;
+ p[3] = n[0];
+ p[4] = n[1];
+ p[5] = n[2];
+
+ return p + 6;
+}
+
+/* Draw a gear wheel. You'll probably want to call this function when
+ * building a display list since we do a lot of trig here.
+ *
+ * Input: inner_radius - radius of hole at center
+ * outer_radius - radius at center of teeth
+ * width - width of gear
+ * teeth - number of teeth
+ * tooth_depth - depth of tooth
+ */
+static struct gear *
+gear(GLfloat inner_radius, GLfloat outer_radius, GLfloat width,
+ GLint teeth, GLfloat tooth_depth)
+{
+ GLint i;
+ GLfloat r0, r1, r2;
+ GLfloat da;
+ GLfloat *p, *v;
+ struct gear *gear;
+ double s[5], c[5];
+ GLfloat verts[3 * 14], normal[3];
+ const int tris_per_tooth = 20;
+
+ gear = malloc(sizeof *gear);
+ if (gear == NULL)
+ return NULL;
+
+ 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;
+
+ gear->vertices = calloc(teeth * tris_per_tooth * 3 * 6,
+ sizeof *gear->vertices);
+ s[4] = 0;
+ c[4] = 1;
+ v = gear->vertices;
+ for (i = 0; i < teeth; i++) {
+ s[0] = s[4];
+ c[0] = c[4];
+ 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]);
+
+ normal[0] = 0.0;
+ normal[1] = 0.0;
+ normal[2] = 1.0;
+
+ v = vert(v, r2 * c[1], r2 * s[1], width * 0.5, normal);
+
+ v = vert(v, r2 * c[1], r2 * s[1], width * 0.5, normal);
+ v = vert(v, r2 * c[2], r2 * s[2], width * 0.5, normal);
+ v = vert(v, r1 * c[0], r1 * s[0], width * 0.5, normal);
+ v = vert(v, r1 * c[3], r1 * s[3], width * 0.5, normal);
+ v = vert(v, r0 * c[0], r0 * s[0], width * 0.5, normal);
+ v = vert(v, r1 * c[4], r1 * s[4], width * 0.5, normal);
+ v = vert(v, r0 * c[4], r0 * s[4], width * 0.5, normal);
+
+ v = vert(v, r0 * c[4], r0 * s[4], width * 0.5, normal);
+ v = vert(v, r0 * c[0], r0 * s[0], width * 0.5, normal);
+ v = vert(v, r0 * c[4], r0 * s[4], -width * 0.5, normal);
+ v = vert(v, r0 * c[0], r0 * s[0], -width * 0.5, normal);
+
+ normal[0] = 0.0;
+ normal[1] = 0.0;
+ normal[2] = -1.0;
+
+ v = vert(v, r0 * c[4], r0 * s[4], -width * 0.5, normal);
+
+ v = vert(v, r0 * c[4], r0 * s[4], -width * 0.5, normal);
+ v = vert(v, r1 * c[4], r1 * s[4], -width * 0.5, normal);
+ v = vert(v, r0 * c[0], r0 * s[0], -width * 0.5, normal);
+ v = vert(v, r1 * c[3], r1 * s[3], -width * 0.5, normal);
+ v = vert(v, r1 * c[0], r1 * s[0], -width * 0.5, normal);
+ v = vert(v, r2 * c[2], r2 * s[2], -width * 0.5, normal);
+ v = vert(v, r2 * c[1], r2 * s[1], -width * 0.5, normal);
+
+ v = vert(v, r1 * c[0], r1 * s[0], width * 0.5, normal);
+
+ v = vert(v, r1 * c[0], r1 * s[0], width * 0.5, normal);
+ v = vert(v, r1 * c[0], r1 * s[0], -width * 0.5, normal);
+ v = vert(v, r2 * c[1], r2 * s[1], width * 0.5, normal);
+ v = vert(v, r2 * c[1], r2 * s[1], -width * 0.5, normal);
+ v = vert(v, r2 * c[2], r2 * s[2], width * 0.5, normal);
+ v = vert(v, r2 * c[2], r2 * s[2], -width * 0.5, normal);
+ v = vert(v, r1 * c[3], r1 * s[3], width * 0.5, normal);
+ v = vert(v, r1 * c[3], r1 * s[3], -width * 0.5, normal);
+ v = vert(v, r1 * c[4], r1 * s[4], width * 0.5, normal);
+ v = vert(v, r1 * c[4], r1 * s[4], -width * 0.5, normal);
+
+ v = vert(v, r1 * c[4], r1 * s[4], -width * 0.5, normal);
+ }
+
+ gear->count = (v - gear->vertices) / 6;
+
+ glGenBuffers(1, &gear->vbo);
+ glBindBuffer(GL_ARRAY_BUFFER, gear->vbo);
+ glBufferData(GL_ARRAY_BUFFER, gear->count * 6 * 4,
+ gear->vertices, GL_STATIC_DRAW);
+
+ return gear;
+}
+
+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);
+}
+
+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);
+}
+
+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);
+}
+
+static const GLfloat light[3] = { 1.0, 1.0, -1.0 };
+
+static void
+draw_gear(struct gear *gear, GLfloat *m,
+ GLfloat x, GLfloat y, GLfloat angle, const GLfloat *color)
+{
+ GLfloat tmp[16];
+
+ memcpy(tmp, m, sizeof tmp);
+ translate(tmp, x, y, 0);
+ rotate(tmp, 2 * M_PI * angle / 360.0, 0, 0, 1);
+ glUniformMatrix4fv(proj_location, 1, GL_FALSE, tmp);
+ glUniform3fv(light_location, 1, light);
+ glUniform4fv(color_location, 1, color);
+
+ glBindBuffer(GL_ARRAY_BUFFER, gear->vbo);
+
+ glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE,
+ 6 * sizeof(GLfloat), NULL);
+ glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE,
+ 6 * sizeof(GLfloat), (GLfloat *) 0 + 3);
+ glEnableVertexAttribArray(0);
+ glEnableVertexAttribArray(1);
+ glDrawArrays(GL_TRIANGLE_STRIP, 0, gear->count);
+}
+
+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 m[16];
+
+ glClearColor(0.0, 0.0, 0.0, 0.0);
+ glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+ memcpy(m, proj, sizeof m);
+ rotate(m, 2 * M_PI * view_rotx / 360.0, 1, 0, 0);
+ rotate(m, 2 * M_PI * view_roty / 360.0, 0, 1, 0);
+ rotate(m, 2 * M_PI * view_rotz / 360.0, 0, 0, 1);
+
+ draw_gear(gear1, m, -3.0, -2.0, angle, red);
+ draw_gear(gear2, m, 3.1, -2.0, -2 * angle - 9.0, green);
+ draw_gear(gear3, m, -3.1, 4.2, -2 * angle - 25.0, blue);
+}
+
+/* new window size or exposure */
+static void
+gears_reshape(int width, int height)
+{
+ GLfloat ar, m[16] = {
+ 1.0, 0.0, 0.0, 0.0,
+ 0.0, 1.0, 0.0, 0.0,
+ 0.0, 0.0, 0.1, 0.0,
+ 0.0, 0.0, 0.0, 1.0,
+ };
+
+ if (width < height)
+ ar = width;
+ else
+ ar = height;
+
+ m[0] = 0.1 * ar / width;
+ m[5] = 0.1 * ar / height;
+ memcpy(proj, m, sizeof proj);
+ glViewport(0, 0, (GLint) width, (GLint) height);
+}
+
+static void
+gears_special(int special)
+{
+ switch (special) {
+ case EGLUT_KEY_LEFT:
+ view_roty += 5.0;
+ break;
+ case EGLUT_KEY_RIGHT:
+ view_roty -= 5.0;
+ break;
+ case EGLUT_KEY_UP:
+ view_rotx += 5.0;
+ break;
+ case EGLUT_KEY_DOWN:
+ view_rotx -= 5.0;
+ break;
+ }
+}
+
+static void
+gears_idle(void)
+{
+ static double tRot0 = -1.0;
+ double dt, t = eglutGet(EGLUT_ELAPSED_TIME) / 1000.0;
+
+ if (tRot0 < 0.0)
+ tRot0 = t;
+ dt = t - tRot0;
+ tRot0 = t;
+
+ /* advance rotation for next frame */
+ angle += 70.0 * dt; /* 70 degrees per second */
+ if (angle > 3600.0)
+ angle -= 3600.0;
+
+ eglutPostRedisplay();
+}
+
+static const char vertex_shader[] =
+ "uniform mat4 proj;\n"
+ "attribute vec4 position;\n"
+ "attribute vec4 normal;\n"
+ "varying vec3 rotated_normal;\n"
+ "varying vec3 rotated_position;\n"
+ "vec4 tmp;\n"
+ "void main()\n"
+ "{\n"
+ " gl_Position = proj * position;\n"
+ " rotated_position = gl_Position.xyz;\n"
+ " tmp = proj * normal;\n"
+ " rotated_normal = tmp.xyz;\n"
+ "}\n";
+
+ static const char fragment_shader[] =
+ //"precision mediump float;\n"
+ "uniform vec4 color;\n"
+ "uniform vec3 light;\n"
+ "varying vec3 rotated_normal;\n"
+ "varying vec3 rotated_position;\n"
+ "vec3 light_direction;\n"
+ "vec4 white = vec4(1.0, 1.0, 1.0, 1.0);\n"
+ "void main()\n"
+ "{\n"
+ " light_direction = normalize(light - rotated_position);\n"
+ " gl_FragColor = color + white * dot(light_direction, rotated_normal);\n"
+ "}\n";
+
+static void
+gears_init(void)
+{
+ GLuint v, f, program;
+ const char *p;
+ char msg[512];
+
+ glEnable(GL_CULL_FACE);
+ glEnable(GL_DEPTH_TEST);
+
+ 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);
+
+ 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);
+
+ 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);
+
+ glUseProgram(program);
+ proj_location = glGetUniformLocation(program, "proj");
+ light_location = glGetUniformLocation(program, "light");
+ color_location = glGetUniformLocation(program, "color");
+
+ /* make the gears */
+ gear1 = gear(1.0, 4.0, 1.0, 20, 0.7);
+ gear2 = gear(0.5, 2.0, 2.0, 10, 0.7);
+ gear3 = gear(1.3, 2.0, 0.5, 10, 0.7);
+}
+
+int
+main(int argc, char *argv[])
+{
+ eglutInitWindowSize(300, 300);
+ eglutInitAPIMask(EGLUT_OPENGL_ES2_BIT);
+ eglutInit(argc, argv);
+
+ eglutCreateWindow("es2gears");
+
+ eglutIdleFunc(gears_idle);
+ eglutReshapeFunc(gears_reshape);
+ eglutDisplayFunc(gears_draw);
+ eglutSpecialFunc(gears_special);
+
+ gears_init();
+
+ eglutMainLoop();
+
+ return 0;
+}
projects / mesa.git / commitdiff