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 #include "texture_enum.h"
  10
  11 #define HSV_WHEEL_SIZE 128
  12
  13 void draw_hsv_wheel(float y, float rad, float theta, float value)
  14 {
  15         glUseProgramObjectARB(0);
  16         check_error();
  17         glActiveTexture(GL_TEXTURE0);
  18         check_error();
  19         glEnable(GL_TEXTURE_2D);
  20         check_error();
  21         glBindTexture(GL_TEXTURE_2D, HSV_WHEEL);
  22         check_error();
  23         glActiveTexture(GL_TEXTURE1);
  24         check_error();
  25         glBindTexture(GL_TEXTURE_2D, 0);
  26         check_error();
  27         glActiveTexture(GL_TEXTURE0);
  28         glEnable(GL_BLEND);
  29         check_error();
  30         glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
  31         check_error();
  32
  33         // wheel
  34         glBegin(GL_QUADS);
  35
  36         glTexCoord2f(0.0f, 1.0f);
  37         glVertex2f(0.0f, y);
  38
  39         glTexCoord2f(1.0f, 1.0f);
  40         glVertex2f(0.2f * 9.0f / 16.0f, y);
  41
  42         glTexCoord2f(1.0f, 0.0f);
  43         glVertex2f(0.2f * 9.0f / 16.0f, y + 0.2f);
  44
  45         glTexCoord2f(0.0f, 0.0f);
  46         glVertex2f(0.0f, y + 0.2f);
  47
  48         glEnd();
  49
  50         // wheel selector
  51         glDisable(GL_TEXTURE_2D);
  52         glColor3f(0.0f, 0.0f, 0.0f);
  53         glPointSize(5.0f);
  54         glBegin(GL_POINTS);
  55         glVertex2f((0.1f + rad * cos(theta) * 0.1f) * 9.0f / 16.0f, y + 0.1f - rad * sin(theta) * 0.1f);
  56         glEnd();
  57
  58         // value slider
  59         glDisable(GL_TEXTURE_2D);
  60         glBegin(GL_QUADS);
  61
  62         glColor3f(0.0f, 0.0f, 0.0f);
  63         glVertex2f(0.22f * 9.0f / 16.0f, y);
  64         glVertex2f(0.24f * 9.0f / 16.0f, y);
  65
  66         glColor3f(1.0f, 1.0f, 1.0f);
  67         glVertex2f(0.24f * 9.0f / 16.0f, y + 0.2f);
  68         glVertex2f(0.22f * 9.0f / 16.0f, y + 0.2f);
  69
  70         glEnd();
  71
  72         // value selector
  73         glColor3f(0.0f, 0.0f, 0.0f);
  74         glPointSize(5.0f);
  75         glBegin(GL_POINTS);
  76         glVertex2f(0.23f * 9.0f / 16.0f, y + value * 0.2f);
  77         glEnd();
  78
  79         glColor3f(1.0f, 1.0f, 1.0f);
  80 }
  81
  82 void draw_saturation_bar(float y, float saturation)
  83 {
  84         glUseProgramObjectARB(0);
  85         check_error();
  86
  87         // value slider
  88         glDisable(GL_TEXTURE_2D);
  89         glBegin(GL_QUADS);
  90
  91         glColor3f(0.0f, 0.0f, 0.0f);
  92         glVertex2f(0.0f * 9.0f / 16.0f, y + 0.02f);
  93         glVertex2f(0.0f * 9.0f / 16.0f, y);
  94
  95         glColor3f(1.0f, 1.0f, 1.0f);
  96         glVertex2f(0.2f * 9.0f / 16.0f, y);
  97         glVertex2f(0.2f * 9.0f / 16.0f, y + 0.02f);
  98
  99         glEnd();
 100
 101         // value selector
 102         glColor3f(0.0f, 0.0f, 0.0f);
 103         glPointSize(5.0f);
 104         glBegin(GL_POINTS);
 105         glVertex2f(0.2f * saturation * 9.0f / 16.0f, y + 0.01f);
 106         glEnd();
 107
 108         glColor3f(1.0f, 1.0f, 1.0f);
 109 }
 110
 111 void make_hsv_wheel_texture()
 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                 printf("\n");
 134         }
 135
 136         glBindTexture(GL_TEXTURE_2D, HSV_WHEEL);
 137         check_error();
 138         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 139         check_error();
 140         glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, HSV_WHEEL_SIZE, HSV_WHEEL_SIZE, 0, GL_RGBA, GL_UNSIGNED_BYTE, hsv_pix);
 141         check_error();
 142 }
 143
 144 void read_colorwheel(float xf, float yf, float *rad, float *theta, float *value)
 145 {
 146         if (xf < 0.2f && yf < 0.2f) {
 147                 float xp = 2.0f * xf / 0.2f - 1.0f;
 148                 float yp = -(2.0f * yf / 0.2f - 1.0f);
 149                 *rad = hypot(xp, yp);
 150                 *theta = atan2(yp, xp);
 151                 if (*rad > 1.0) {
 152                         *rad = 1.0;
 153                 }
 154         } else if (xf >= 0.22f && xf <= 0.24f) {
 155                 *value = yf / 0.2f;
 156         }
 157 }
 158