git.sesse.net Git - movit/blob - widgets.cpp

   1 #define GL_GLEXT_PROTOTYPES 1
   2
   3 #include <math.h>
   4 #include <GL/gl.h>
   5 #include <GL/glext.h>
   6
   7 #include "widgets.h"
   8 #include "util.h"
   9
  10 #define HSV_WHEEL_SIZE 128
  11
  12 GLuint hsv_wheel_num;
  13
  14 void draw_hsv_wheel(float y, float rad, float theta, float value)
  15 {
  16         glUseProgram(0);
  17         check_error();
  18         glActiveTexture(GL_TEXTURE0);
  19         check_error();
  20         glEnable(GL_TEXTURE_2D);
  21         check_error();
  22         glBindTexture(GL_TEXTURE_2D, hsv_wheel_num);
  23         check_error();
  24         glActiveTexture(GL_TEXTURE1);
  25         check_error();
  26         glBindTexture(GL_TEXTURE_2D, 0);
  27         check_error();
  28         glActiveTexture(GL_TEXTURE0);
  29         glEnable(GL_BLEND);
  30         check_error();
  31         glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
  32         check_error();
  33
  34         // wheel
  35         glBegin(GL_QUADS);
  36
  37         glTexCoord2f(0.0f, 1.0f);
  38         glVertex2f(0.0f, y);
  39
  40         glTexCoord2f(1.0f, 1.0f);
  41         glVertex2f(0.2f * 9.0f / 16.0f, y);
  42
  43         glTexCoord2f(1.0f, 0.0f);
  44         glVertex2f(0.2f * 9.0f / 16.0f, y + 0.2f);
  45
  46         glTexCoord2f(0.0f, 0.0f);
  47         glVertex2f(0.0f, y + 0.2f);
  48
  49         glEnd();
  50
  51         // wheel selector
  52         glDisable(GL_TEXTURE_2D);
  53         glColor3f(0.0f, 0.0f, 0.0f);
  54         glPointSize(5.0f);
  55         glBegin(GL_POINTS);
  56         glVertex2f((0.1f + rad * cos(theta) * 0.1f) * 9.0f / 16.0f, y + 0.1f - rad * sin(theta) * 0.1f);
  57         glEnd();
  58
  59         // value slider
  60         glDisable(GL_TEXTURE_2D);
  61         glBegin(GL_QUADS);
  62
  63         glColor3f(0.0f, 0.0f, 0.0f);
  64         glVertex2f(0.22f * 9.0f / 16.0f, y);
  65         glVertex2f(0.24f * 9.0f / 16.0f, y);
  66
  67         glColor3f(1.0f, 1.0f, 1.0f);
  68         glVertex2f(0.24f * 9.0f / 16.0f, y + 0.2f);
  69         glVertex2f(0.22f * 9.0f / 16.0f, y + 0.2f);
  70
  71         glEnd();
  72
  73         // value selector
  74         glColor3f(0.0f, 0.0f, 0.0f);
  75         glPointSize(5.0f);
  76         glBegin(GL_POINTS);
  77         glVertex2f(0.23f * 9.0f / 16.0f, y + value * 0.2f);
  78         glEnd();
  79
  80         glColor3f(1.0f, 1.0f, 1.0f);
  81 }
  82
  83 void draw_saturation_bar(float y, float saturation)
  84 {
  85         glUseProgram(0);
  86         check_error();
  87
  88         // value slider
  89         glDisable(GL_TEXTURE_2D);
  90         glBegin(GL_QUADS);
  91
  92         glColor3f(0.0f, 0.0f, 0.0f);
  93         glVertex2f(0.0f * 9.0f / 16.0f, y + 0.02f);
  94         glVertex2f(0.0f * 9.0f / 16.0f, y);
  95
  96         glColor3f(1.0f, 1.0f, 1.0f);
  97         glVertex2f(0.2f * 9.0f / 16.0f, y);
  98         glVertex2f(0.2f * 9.0f / 16.0f, y + 0.02f);
  99
 100         glEnd();
 101
 102         // value selector
 103         glColor3f(0.0f, 0.0f, 0.0f);
 104         glPointSize(5.0f);
 105         glBegin(GL_POINTS);
 106         glVertex2f(0.2f * saturation * 9.0f / 16.0f, y + 0.01f);
 107         glEnd();
 108
 109         glColor3f(1.0f, 1.0f, 1.0f);
 110 }
 111
 112 void make_hsv_wheel_texture()
 113 {
 114         glGenTextures(1, &hsv_wheel_num);
 115
 116         static unsigned char hsv_pix[HSV_WHEEL_SIZE * HSV_WHEEL_SIZE * 4];
 117         for (int y = 0; y < HSV_WHEEL_SIZE; ++y) {
 118                 for (int x = 0; x < HSV_WHEEL_SIZE; ++x) {
 119                         float yf = 2.0f * y / (float)(HSV_WHEEL_SIZE) - 1.0f;
 120                         float xf = 2.0f * x / (float)(HSV_WHEEL_SIZE) - 1.0f;
 121                         float rad = hypot(xf, yf);
 122                         float theta = atan2(yf, xf);
 123
 124                         float r, g, b;
 125                         hsv2rgb(theta, rad, 1.0f, &r, &g, &b);
 126                         hsv_pix[(y * HSV_WHEEL_SIZE + x) * 4 + 0] = lrintf(r * 255.0f);
 127                         hsv_pix[(y * HSV_WHEEL_SIZE + x) * 4 + 1] = lrintf(g * 255.0f);
 128                         hsv_pix[(y * HSV_WHEEL_SIZE + x) * 4 + 2] = lrintf(b * 255.0f);
 129
 130                         if (rad > 1.0f) {
 131                                 hsv_pix[(y * HSV_WHEEL_SIZE + x) * 4 + 3] = 0;
 132                         } else {
 133                                 hsv_pix[(y * HSV_WHEEL_SIZE + x) * 4 + 3] = 255;
 134                         }
 135                 }
 136                 printf("\n");
 137         }
 138
 139         glBindTexture(GL_TEXTURE_2D, hsv_wheel_num);
 140         check_error();
 141         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 142         check_error();
 143         glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, HSV_WHEEL_SIZE, HSV_WHEEL_SIZE, 0, GL_RGBA, GL_UNSIGNED_BYTE, hsv_pix);
 144         check_error();
 145 }
 146
 147 void read_colorwheel(float xf, float yf, float *rad, float *theta, float *value)
 148 {
 149         if (xf < 0.2f && yf < 0.2f) {
 150                 float xp = 2.0f * xf / 0.2f - 1.0f;
 151                 float yp = -(2.0f * yf / 0.2f - 1.0f);
 152                 *rad = hypot(xp, yp);
 153                 *theta = atan2(yp, xp);
 154                 if (*rad > 1.0) {
 155                         *rad = 1.0;
 156                 }
 157         } else if (xf >= 0.22f && xf <= 0.24f) {
 158                 *value = yf / 0.2f;
 159         }
 160 }
 161