Actual source code: drawimage.h
1: #pragma once
3: #include <petscdraw.h>
5: typedef struct _n_PetscImage *PetscImage;
6: typedef struct _n_PetscImage {
7: unsigned char *buffer; /* raster buffer */
8: int w, h; /* width, height */
9: int clip[4]; /* clip ranges */
10: unsigned char palette[256][3]; /* colormap */
11: } _n_PetscImage;
13: static inline void PetscImageSetClip(PetscImage img, int x, int y, int w, int h)
14: {
15: img->clip[0] = PetscClipInterval(x, 0, img->w - 1); /* xmin */
16: img->clip[1] = PetscClipInterval(y, 0, img->h - 1); /* ymin */
17: img->clip[2] = PetscClipInterval(x + w, 0, img->w); /* xmax+1 */
18: img->clip[3] = PetscClipInterval(y + h, 0, img->h); /* ymax+1 */
19: }
21: static inline void PetscImageClear(PetscImage img)
22: {
23: int x, xs = img->clip[0], xe = img->clip[2];
24: int y, ys = img->clip[1], ye = img->clip[3];
25: for (y = ys; y < ye; y++)
26: for (x = xs; x < xe; x++) img->buffer[y * img->w + x] = 0;
27: }
29: static inline void PetscImageDrawPixel(PetscImage img, int x, int y, int c)
30: {
31: if (x < img->clip[0] || x >= img->clip[2]) return;
32: if (y < img->clip[1] || y >= img->clip[3]) return;
33: img->buffer[y * img->w + x] = (unsigned char)c;
34: }
36: static inline void PetscImageDrawLine(PetscImage img, int x_1, int y_1, int x_2, int y_2, int c)
37: {
38: if (y_1 == y_2) {
39: /* Horizontal line */
40: if (x_2 - x_1 < 0) {
41: int tmp = x_1;
42: x_1 = x_2;
43: x_2 = tmp;
44: }
45: while (x_1 <= x_2) PetscImageDrawPixel(img, x_1++, y_1, c);
46: } else if (x_1 == x_2) {
47: /* Vertical line */
48: if (y_2 - y_1 < 0) {
49: int tmp = y_1;
50: y_1 = y_2;
51: y_2 = tmp;
52: }
53: while (y_1 <= y_2) PetscImageDrawPixel(img, x_1, y_1++, c);
54: } else {
55: /* Bresenham's line drawing algorithm */
56: int dx = PetscAbs(x_2 - x_1), sx = (x_2 - x_1) >= 0 ? +1 : -1;
57: int dy = PetscAbs(y_2 - y_1), sy = (y_2 - y_1) >= 0 ? +1 : -1;
58: int error = (dx > dy ? dx : -dy) / 2, err;
59: while (1) {
60: PetscImageDrawPixel(img, x_1, y_1, c);
61: if (x_1 == x_2 && y_1 == y_2) break;
62: err = error;
63: if (err > -dx) {
64: error -= dy;
65: x_1 += sx;
66: }
67: if (err < +dy) {
68: error += dx;
69: y_1 += sy;
70: }
71: }
72: }
73: }
75: static inline void PetscImageDrawRectangle(PetscImage img, int x, int y, int w, int h, int c)
76: {
77: int xs = PetscMax(x, img->clip[0]), xe = PetscMin(x + w, img->clip[2]);
78: int ys = PetscMax(y, img->clip[1]), ye = PetscMin(y + h, img->clip[3]);
79: if (xs >= xe || ys >= ye) return;
80: for (y = ys; y < ye; y++)
81: for (x = xs; x < xe; x++) img->buffer[y * img->w + x] = (unsigned char)c;
82: }
84: static inline void PetscImageDrawEllipse(PetscImage img, int xc, int yc, int w, int h, int c)
85: {
86: /* Bresenham's circle/ellipse drawing algorithm */
87: int x, y, s, a2 = w * w, b2 = h * h;
88: for (x = 0, y = h, s = 2 * b2 + a2 * (1 - 2 * h); b2 * x <= a2 * y; x++) {
89: PetscImageDrawLine(img, xc + x, yc + y, xc - x, yc + y, c);
90: PetscImageDrawLine(img, xc + x, yc - y, xc - x, yc - y, c);
91: if (s >= 0) {
92: s += 4 * a2 * (1 - y);
93: y--;
94: }
95: s += b2 * ((4 * x) + 6);
96: }
97: for (x = w, y = 0, s = 2 * a2 + b2 * (1 - 2 * w); a2 * y <= b2 * x; y++) {
98: PetscImageDrawLine(img, xc + x, yc + y, xc - x, yc + y, c);
99: PetscImageDrawLine(img, xc + x, yc - y, xc - x, yc - y, c);
100: if (s >= 0) {
101: s += 4 * b2 * (1 - x);
102: x--;
103: }
104: s += a2 * ((4 * y) + 6);
105: }
106: }
108: static inline void PetscImageDrawTriangle(PetscImage img, int x_1, int y_1, int t_1, int x_2, int y_2, int t_2, int x_3, int y_3, int t_3)
109: {
110: const int SHIFT_VAL = 6;
111: const int xmin = img->clip[0], xmax = img->clip[2] - 1;
112: const int ymin = img->clip[1], ymax = img->clip[3] - 1;
113: float rfrac, lfrac, one = 1;
114: float R_y2_y1, R_y3_y1, R_y3_y2;
115: int lc, rc = 0, lx, rx = 0, xx, y, c;
116: int rc_lc, rx_lx, t2_t1, x2_x1, t3_t1, x3_x1, t3_t2, x3_x2;
118: /* Is triangle ever visible in image? */
119: if (x_1 < xmin && x_2 < xmin && x_3 < xmin) return;
120: if (y_1 < ymin && y_2 < ymin && y_3 < ymin) return;
121: if (x_1 > xmax && x_2 > xmax && x_3 > xmax) return;
122: if (y_1 > ymax && y_2 > ymax && y_3 > ymax) return;
124: t_1 = t_1 << SHIFT_VAL;
125: t_2 = t_2 << SHIFT_VAL;
126: t_3 = t_3 << SHIFT_VAL;
128: /* Sort the vertices */
129: #define SWAP(a, b) \
130: do { \
131: int _tmp; \
132: _tmp = a; \
133: a = b; \
134: b = _tmp; \
135: } while (0)
136: if (y_1 > y_2) {
137: SWAP(x_1, x_2);
138: SWAP(y_1, y_2);
139: SWAP(t_1, t_2);
140: }
141: if (y_1 > y_3) {
142: SWAP(x_1, x_3);
143: SWAP(y_1, y_3);
144: SWAP(t_1, t_3);
145: }
146: if (y_2 > y_3) {
147: SWAP(x_2, x_3);
148: SWAP(y_2, y_3);
149: SWAP(t_2, t_3);
150: }
151: #undef SWAP
153: /* This code is decidedly non-optimal;
154: it is intended to be a start at an implementation */
156: t2_t1 = t_2 - t_1;
157: x2_x1 = x_2 - x_1;
158: R_y2_y1 = (y_2 != y_1) ? one / (y_2 - y_1) : 0;
159: R_y3_y1 = (y_3 != y_1) ? one / (y_3 - y_1) : 0;
160: x3_x1 = x_3 - x_1;
161: t3_t1 = t_3 - t_1;
163: for (y = y_1; y <= y_2; y++) {
164: /* Draw a line with the correct color from t1-t2 to t1-t3 */
165: /* Left color is (y-y1)/(y2-y1) * (t2-t1) + t1 */
166: lfrac = (y - y_1) * R_y2_y1;
167: lc = (int)(lfrac * (t2_t1) + t_1);
168: lx = (int)(lfrac * (x2_x1) + x_1);
169: /* Right color is (y-y1)/(y3-y1) * (t3-t1) + t1 */
170: rfrac = (y - y_1) * R_y3_y1;
171: rc = (int)(rfrac * (t3_t1) + t_1);
172: rx = (int)(rfrac * (x3_x1) + x_1);
173: /* Draw the line */
174: rc_lc = rc - lc;
175: rx_lx = rx - lx;
176: if (rx > lx) {
177: for (xx = lx; xx <= rx; xx++) {
178: c = (((xx - lx) * (rc_lc)) / (rx_lx) + lc) >> SHIFT_VAL;
179: PetscImageDrawPixel(img, xx, y, c);
180: }
181: } else if (rx < lx) {
182: for (xx = lx; xx >= rx; xx--) {
183: c = (((xx - lx) * (rc_lc)) / (rx_lx) + lc) >> SHIFT_VAL;
184: PetscImageDrawPixel(img, xx, y, c);
185: }
186: } else {
187: c = lc >> SHIFT_VAL;
188: PetscImageDrawPixel(img, lx, y, c);
189: }
190: }
192: /* For simplicity,"move" t1 to the intersection of t1-t3 with the line y=y2.
193: We take advantage of the previous iteration. */
194: if (y_2 >= y_3) return;
195: if (y_1 < y_2) {
196: x_1 = rx;
197: y_1 = y_2;
198: t_1 = rc;
199: x3_x1 = x_3 - x_1;
200: t3_t1 = t_3 - t_1;
201: }
202: R_y3_y1 = (y_3 != y_1) ? one / (y_3 - y_1) : 0;
203: R_y3_y2 = (y_3 != y_2) ? one / (y_3 - y_2) : 0;
204: x3_x2 = x_3 - x_2;
205: t3_t2 = t_3 - t_2;
207: for (y = y_2; y <= y_3; y++) {
208: /* Draw a line with the correct color from t2-t3 to t1-t3 */
209: /* Left color is (y-y1)/(y2-y1) * (t2-t1) + t1 */
210: lfrac = (y - y_2) * R_y3_y2;
211: lc = (int)(lfrac * (t3_t2) + t_2);
212: lx = (int)(lfrac * (x3_x2) + x_2);
213: /* Right color is (y-y1)/(y3-y1) * (t3-t1) + t1 */
214: rfrac = (y - y_1) * R_y3_y1;
215: rc = (int)(rfrac * (t3_t1) + t_1);
216: rx = (int)(rfrac * (x3_x1) + x_1);
217: /* Draw the line */
218: rc_lc = rc - lc;
219: rx_lx = rx - lx;
220: if (rx > lx) {
221: for (xx = lx; xx <= rx; xx++) {
222: c = (((xx - lx) * (rc_lc)) / (rx_lx) + lc) >> SHIFT_VAL;
223: PetscImageDrawPixel(img, xx, y, c);
224: }
225: } else if (rx < lx) {
226: for (xx = lx; xx >= rx; xx--) {
227: c = (((xx - lx) * (rc_lc)) / (rx_lx) + lc) >> SHIFT_VAL;
228: PetscImageDrawPixel(img, xx, y, c);
229: }
230: } else {
231: c = lc >> SHIFT_VAL;
232: PetscImageDrawPixel(img, lx, y, c);
233: }
234: }
235: }
237: #define PetscImageFontWidth 6
238: #define PetscImageFontHeight 10
239: static const unsigned char PetscImageFontBitmap[128 - 32][10] = {
240: {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}, /* */
241: {0x00, 0x08, 0x08, 0x08, 0x08, 0x08, 0x00, 0x08, 0x00, 0x00}, /* ! */
242: {0x00, 0x14, 0x14, 0x14, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}, /* " */
243: {0x00, 0x14, 0x14, 0x3E, 0x14, 0x3E, 0x14, 0x14, 0x00, 0x00}, /* # */
244: {0x00, 0x08, 0x1C, 0x28, 0x1C, 0x0A, 0x1C, 0x08, 0x00, 0x00}, /* $ */
245: {0x00, 0x12, 0x2A, 0x14, 0x08, 0x14, 0x2A, 0x24, 0x00, 0x00}, /* % */
246: {0x00, 0x10, 0x28, 0x28, 0x10, 0x2A, 0x24, 0x1A, 0x00, 0x00}, /* & */
247: {0x00, 0x08, 0x08, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}, /* ' */
248: {0x00, 0x04, 0x08, 0x10, 0x10, 0x10, 0x08, 0x04, 0x00, 0x00}, /* ( */
249: {0x00, 0x10, 0x08, 0x04, 0x04, 0x04, 0x08, 0x10, 0x00, 0x00}, /*) */
250: {0x00, 0x00, 0x22, 0x14, 0x3E, 0x14, 0x22, 0x00, 0x00, 0x00}, /* * */
251: {0x00, 0x00, 0x08, 0x08, 0x3E, 0x08, 0x08, 0x00, 0x00, 0x00}, /* + */
252: {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0C, 0x08, 0x10, 0x00}, /* , */
253: {0x00, 0x00, 0x00, 0x00, 0x3E, 0x00, 0x00, 0x00, 0x00, 0x00}, /* - */
254: {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x08, 0x1C, 0x08, 0x00}, /* . */
255: {0x00, 0x02, 0x02, 0x04, 0x08, 0x10, 0x20, 0x20, 0x00, 0x00}, /* / */
256: {0x00, 0x08, 0x14, 0x22, 0x22, 0x22, 0x14, 0x08, 0x00, 0x00}, /* 0 */
257: {0x00, 0x08, 0x18, 0x28, 0x08, 0x08, 0x08, 0x3E, 0x00, 0x00}, /* 1 */
258: {0x00, 0x1C, 0x22, 0x02, 0x0C, 0x10, 0x20, 0x3E, 0x00, 0x00}, /* 2 */
259: {0x00, 0x3E, 0x02, 0x04, 0x0C, 0x02, 0x22, 0x1C, 0x00, 0x00}, /* 3 */
260: {0x00, 0x04, 0x0C, 0x14, 0x24, 0x3E, 0x04, 0x04, 0x00, 0x00}, /* 4 */
261: {0x00, 0x3E, 0x20, 0x2C, 0x32, 0x02, 0x22, 0x1C, 0x00, 0x00}, /* 5 */
262: {0x00, 0x0C, 0x10, 0x20, 0x2C, 0x32, 0x22, 0x1C, 0x00, 0x00}, /* 6 */
263: {0x00, 0x3E, 0x02, 0x04, 0x04, 0x08, 0x10, 0x10, 0x00, 0x00}, /* 7 */
264: {0x00, 0x1C, 0x22, 0x22, 0x1C, 0x22, 0x22, 0x1C, 0x00, 0x00}, /* 8 */
265: {0x00, 0x1C, 0x22, 0x26, 0x1A, 0x02, 0x04, 0x18, 0x00, 0x00}, /* 9 */
266: {0x00, 0x00, 0x08, 0x1C, 0x08, 0x00, 0x08, 0x1C, 0x08, 0x00}, /* : */
267: {0x00, 0x00, 0x08, 0x1C, 0x08, 0x00, 0x0C, 0x08, 0x10, 0x00}, /* } */
268: {0x00, 0x02, 0x04, 0x08, 0x10, 0x08, 0x04, 0x02, 0x00, 0x00}, /* < */
269: {0x00, 0x00, 0x00, 0x3E, 0x00, 0x3E, 0x00, 0x00, 0x00, 0x00}, /* = */
270: {0x00, 0x10, 0x08, 0x04, 0x02, 0x04, 0x08, 0x10, 0x00, 0x00}, /* > */
271: {0x00, 0x1C, 0x22, 0x04, 0x08, 0x08, 0x00, 0x08, 0x00, 0x00}, /* ? */
272: {0x00, 0x1C, 0x22, 0x26, 0x2A, 0x2C, 0x20, 0x1C, 0x00, 0x00}, /* @ */
273: {0x00, 0x08, 0x14, 0x22, 0x22, 0x3E, 0x22, 0x22, 0x00, 0x00}, /* A */
274: {0x00, 0x3C, 0x12, 0x12, 0x1C, 0x12, 0x12, 0x3C, 0x00, 0x00}, /* B */
275: {0x00, 0x1C, 0x22, 0x20, 0x20, 0x20, 0x22, 0x1C, 0x00, 0x00}, /* C */
276: {0x00, 0x3C, 0x12, 0x12, 0x12, 0x12, 0x12, 0x3C, 0x00, 0x00}, /* D */
277: {0x00, 0x3E, 0x20, 0x20, 0x3C, 0x20, 0x20, 0x3E, 0x00, 0x00}, /* E */
278: {0x00, 0x3E, 0x20, 0x20, 0x3C, 0x20, 0x20, 0x20, 0x00, 0x00}, /* F */
279: {0x00, 0x1C, 0x22, 0x20, 0x20, 0x26, 0x22, 0x1C, 0x00, 0x00}, /* G */
280: {0x00, 0x22, 0x22, 0x22, 0x3E, 0x22, 0x22, 0x22, 0x00, 0x00}, /* H */
281: {0x00, 0x1C, 0x08, 0x08, 0x08, 0x08, 0x08, 0x1C, 0x00, 0x00}, /* I */
282: {0x00, 0x0E, 0x04, 0x04, 0x04, 0x04, 0x24, 0x18, 0x00, 0x00}, /* J */
283: {0x00, 0x22, 0x24, 0x28, 0x30, 0x28, 0x24, 0x22, 0x00, 0x00}, /* K */
284: {0x00, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x3E, 0x00, 0x00}, /* L */
285: {0x00, 0x22, 0x22, 0x36, 0x2A, 0x22, 0x22, 0x22, 0x00, 0x00}, /* M */
286: {0x00, 0x22, 0x22, 0x32, 0x2A, 0x26, 0x22, 0x22, 0x00, 0x00}, /* N */
287: {0x00, 0x1C, 0x22, 0x22, 0x22, 0x22, 0x22, 0x1C, 0x00, 0x00}, /* O */
288: {0x00, 0x3C, 0x22, 0x22, 0x3C, 0x20, 0x20, 0x20, 0x00, 0x00}, /* P */
289: {0x00, 0x1C, 0x22, 0x22, 0x22, 0x22, 0x2A, 0x1C, 0x02, 0x00}, /* Q */
290: {0x00, 0x3C, 0x22, 0x22, 0x3C, 0x28, 0x24, 0x22, 0x00, 0x00}, /* R */
291: {0x00, 0x1C, 0x22, 0x20, 0x1C, 0x02, 0x22, 0x1C, 0x00, 0x00}, /* S */
292: {0x00, 0x3E, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x00, 0x00}, /* T */
293: {0x00, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x1C, 0x00, 0x00}, /* U */
294: {0x00, 0x22, 0x22, 0x22, 0x14, 0x14, 0x14, 0x08, 0x00, 0x00}, /* V */
295: {0x00, 0x22, 0x22, 0x22, 0x2A, 0x2A, 0x36, 0x22, 0x00, 0x00}, /* W */
296: {0x00, 0x22, 0x22, 0x14, 0x08, 0x14, 0x22, 0x22, 0x00, 0x00}, /* X */
297: {0x00, 0x22, 0x22, 0x14, 0x08, 0x08, 0x08, 0x08, 0x00, 0x00}, /* Y */
298: {0x00, 0x3E, 0x02, 0x04, 0x08, 0x10, 0x20, 0x3E, 0x00, 0x00}, /* Z */
299: {0x00, 0x1C, 0x10, 0x10, 0x10, 0x10, 0x10, 0x1C, 0x00, 0x00}, /* [ */
300: {0x00, 0x20, 0x20, 0x10, 0x08, 0x04, 0x02, 0x02, 0x00, 0x00}, /* \ */
301: {0x00, 0x1C, 0x04, 0x04, 0x04, 0x04, 0x04, 0x1C, 0x00, 0x00}, /* ] */
302: {0x00, 0x08, 0x14, 0x22, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}, /* ^ */
303: {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x3E, 0x00}, /* _ */
304: {0x08, 0x04, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}, /* ` */
305: {0x00, 0x00, 0x00, 0x1C, 0x02, 0x1E, 0x22, 0x1E, 0x00, 0x00}, /* a */
306: {0x00, 0x20, 0x20, 0x2C, 0x32, 0x22, 0x32, 0x2C, 0x00, 0x00}, /* b */
307: {0x00, 0x00, 0x00, 0x1C, 0x22, 0x20, 0x22, 0x1C, 0x00, 0x00}, /* c */
308: {0x00, 0x02, 0x02, 0x1A, 0x26, 0x22, 0x26, 0x1A, 0x00, 0x00}, /* d */
309: {0x00, 0x00, 0x00, 0x1C, 0x22, 0x3E, 0x20, 0x1C, 0x00, 0x00}, /* e */
310: {0x00, 0x0C, 0x12, 0x10, 0x3C, 0x10, 0x10, 0x10, 0x00, 0x00}, /* f */
311: {0x00, 0x00, 0x00, 0x1E, 0x22, 0x22, 0x1E, 0x02, 0x22, 0x1C}, /* g */
312: {0x00, 0x20, 0x20, 0x2C, 0x32, 0x22, 0x22, 0x22, 0x00, 0x00}, /* h */
313: {0x00, 0x08, 0x00, 0x18, 0x08, 0x08, 0x08, 0x1C, 0x00, 0x00}, /* i */
314: {0x00, 0x02, 0x00, 0x06, 0x02, 0x02, 0x02, 0x12, 0x12, 0x0C}, /* j */
315: {0x00, 0x20, 0x20, 0x22, 0x24, 0x38, 0x24, 0x22, 0x00, 0x00}, /* k */
316: {0x00, 0x18, 0x08, 0x08, 0x08, 0x08, 0x08, 0x1C, 0x00, 0x00}, /* l */
317: {0x00, 0x00, 0x00, 0x34, 0x2A, 0x2A, 0x2A, 0x22, 0x00, 0x00}, /* m */
318: {0x00, 0x00, 0x00, 0x2C, 0x32, 0x22, 0x22, 0x22, 0x00, 0x00}, /* n */
319: {0x00, 0x00, 0x00, 0x1C, 0x22, 0x22, 0x22, 0x1C, 0x00, 0x00}, /* o */
320: {0x00, 0x00, 0x00, 0x2C, 0x32, 0x22, 0x32, 0x2C, 0x20, 0x20}, /* p */
321: {0x00, 0x00, 0x00, 0x1A, 0x26, 0x22, 0x26, 0x1A, 0x02, 0x02}, /* q */
322: {0x00, 0x00, 0x00, 0x2C, 0x32, 0x20, 0x20, 0x20, 0x00, 0x00}, /* r */
323: {0x00, 0x00, 0x00, 0x1C, 0x20, 0x1C, 0x02, 0x3C, 0x00, 0x00}, /* s */
324: {0x00, 0x10, 0x10, 0x3C, 0x10, 0x10, 0x12, 0x0C, 0x00, 0x00}, /* t */
325: {0x00, 0x00, 0x00, 0x22, 0x22, 0x22, 0x26, 0x1A, 0x00, 0x00}, /* u */
326: {0x00, 0x00, 0x00, 0x22, 0x22, 0x14, 0x14, 0x08, 0x00, 0x00}, /* v */
327: {0x00, 0x00, 0x00, 0x22, 0x22, 0x2A, 0x2A, 0x14, 0x00, 0x00}, /* w */
328: {0x00, 0x00, 0x00, 0x22, 0x14, 0x08, 0x14, 0x22, 0x00, 0x00}, /* x */
329: {0x00, 0x00, 0x00, 0x22, 0x22, 0x26, 0x1A, 0x02, 0x22, 0x1C}, /* y */
330: {0x00, 0x00, 0x00, 0x3E, 0x04, 0x08, 0x10, 0x3E, 0x00, 0x00}, /* z */
331: {0x00, 0x06, 0x08, 0x04, 0x18, 0x04, 0x08, 0x06, 0x00, 0x00}, /* { */
332: {0x00, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x00, 0x00}, /* | */
333: {0x00, 0x18, 0x04, 0x08, 0x06, 0x08, 0x04, 0x18, 0x00, 0x00}, /* } */
334: {0x00, 0x12, 0x2A, 0x24, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}, /* ~ */
335: {0x00, 0x2A, 0x00, 0x22, 0x00, 0x22, 0x00, 0x2A, 0x00, 0x00}, /* ASCII 127 */
336: };
338: static inline void PetscImageDrawText(PetscImage img, int x, int y, int c, const char text[])
339: {
340: int i, j, k, tw = PetscImageFontWidth, th = PetscImageFontHeight;
341: for (i = 0; i < th; i++) {
342: for (k = 0; text[k]; k++) {
343: int chr = PetscClipInterval(text[k], 32, 127);
344: for (j = 0; j < tw; j++) {
345: if (PetscImageFontBitmap[chr - 32][i] & (1 << (tw - 1 - j))) PetscImageDrawPixel(img, x + j + k * tw, y + i - th, c);
346: }
347: }
348: }
349: }