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

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