Add Pamtris

git-svn-id: http://svn.code.sf.net/p/netpbm/code/trunk@3298 9d0c8265-081b-0410-96cb-a4ca84ce46f8

1 files changed, 252 insertions, 0 deletions

diff --git a/generator/pamtris/framebuffer.c b/generator/pamtris/framebuffer.c
new file mode 100644
index 00000000..cbb1e4a8
--- /dev/null
+++ b/generator/pamtris/framebuffer.c
@@ -0,0 +1,252 @@
+#include <stdlib.h>
+#include <string.h>
+
+#include "common.h"
+
+
+
+int
+set_tupletype(const char * str,
+              char         tupletype[256]) {
+
+    if (str == NULL) {
+        memset(tupletype, 0, 256);
+
+        return 1;
+    } else {
+        size_t len = strlen(str);
+
+        if (len > 255) {
+            return 0;
+        }
+
+        if (len > 0) {
+            memcpy(tupletype, str, len);
+        }
+
+        tupletype[len--] = '\0';
+
+        while(len > 0 && isspace(tupletype[len])) {
+            tupletype[len--] = '\0';
+        }
+
+        return 1;
+    }
+}
+
+
+
+int
+init_framebuffer(framebuffer_info * fbi) {
+
+    uint8_t num_planes = fbi->num_attribs + 1;
+
+    uint32_t elements = fbi->width * fbi->height;
+
+    fbi->img.bytes = elements * (num_planes * sizeof(uint16_t));
+    fbi->z.bytes = elements * sizeof(uint32_t);
+
+    fbi->img.buffer =
+        calloc(fbi->img.bytes / sizeof(uint16_t), sizeof(uint16_t));
+    fbi->z.buffer =
+        calloc(fbi->z.bytes / sizeof(uint32_t), sizeof(uint32_t));
+
+    if(fbi->img.buffer == NULL || fbi->z.buffer == NULL)
+    {
+        free(fbi->img.buffer);
+        free(fbi->z.buffer);
+
+        return 0;
+    }
+
+    fbi->outpam.size = sizeof(struct pam);
+    fbi->outpam.len = sizeof(struct pam);
+    fbi->outpam.file = stdout;
+    fbi->outpam.format = PAM_FORMAT;
+    fbi->outpam.plainformat = 0;
+    fbi->outpam.height = fbi->height;
+    fbi->outpam.width = fbi->width;
+    fbi->outpam.depth = num_planes;
+    fbi->outpam.maxval = fbi->maxval;
+    fbi->outpam.allocation_depth = 0;
+    fbi->outpam.comment_p = NULL;
+
+    fbi->pamrow = NULL;
+    fbi->pamrow = pnm_allocpamrow(&fbi->outpam);
+
+    if (fbi->pamrow == NULL) {
+        free(fbi->img.buffer);
+        free(fbi->z.buffer);
+
+        return 0;
+    }
+
+    return 1;
+}
+
+
+
+void
+free_framebuffer(framebuffer_info * fbi) {
+
+    free(fbi->img.buffer);
+    free(fbi->z.buffer);
+
+    pnm_freepamrow(fbi->pamrow);
+}
+
+
+
+int
+realloc_image_buffer(int32_t            new_maxval,
+                     int32_t            new_num_attribs,
+                     framebuffer_info * fbi) {
+
+    uint8_t num_planes = fbi->num_attribs + 1;
+
+    pnm_freepamrow(fbi->pamrow);
+    fbi->pamrow = NULL;
+
+    if (new_num_attribs != fbi->num_attribs) {
+        fbi->num_attribs = new_num_attribs;
+        num_planes = fbi->num_attribs + 1;
+
+        fbi->img.bytes =
+            fbi->width * fbi->height * (num_planes * sizeof(uint16_t));
+
+        {
+            uint16_t* new_ptr = realloc(fbi->img.buffer, fbi->img.bytes);
+
+            if (new_ptr == NULL) {
+                free(fbi->img.buffer);
+                fbi->img.buffer = NULL;
+
+                return 0;
+            }
+            fbi->img.buffer = new_ptr;
+        }
+    }
+
+    fbi->maxval = new_maxval;
+
+    fbi->outpam.size             = sizeof(struct pam);
+    fbi->outpam.len              = sizeof(struct pam);
+    fbi->outpam.file             = stdout;
+    fbi->outpam.format           = PAM_FORMAT;
+    fbi->outpam.plainformat      = 0;
+    fbi->outpam.height           = fbi->height;
+    fbi->outpam.width            = fbi->width;
+    fbi->outpam.depth            = num_planes;
+    fbi->outpam.maxval           = fbi->maxval;
+    fbi->outpam.allocation_depth = 0;
+    fbi->outpam.comment_p        = NULL;
+
+    fbi->pamrow = pnm_allocpamrow(&fbi->outpam);
+
+    if (fbi->pamrow == NULL) {
+        free(fbi->img.buffer);
+        fbi->img.buffer = NULL;
+
+        return 0;
+    }
+
+    memset(fbi->img.buffer, 0, fbi->img.bytes);
+
+    return 1;
+}
+
+
+
+void
+print_framebuffer(framebuffer_info * fbi) {
+
+    uint8_t num_planes = fbi->num_attribs + 1;
+    uint32_t i = 0;
+    uint32_t end = fbi->width * fbi->height;
+
+    pnm_writepaminit(&fbi->outpam);
+
+    while (i != end) {
+        int j;
+        for (j = 0; j < fbi->width; j++) {
+            uint32_t k = (i + j) * num_planes;
+
+            unsigned int l;
+
+            for (l = 0; l < num_planes; l++) {
+                fbi->pamrow[j][l] = fbi->img.buffer[k + l];
+            }
+        }
+
+        pnm_writepamrow(&fbi->outpam, fbi->pamrow);
+
+        i += fbi->width;
+    }
+}
+
+
+
+void
+clear_framebuffer(bool              clear_image_buffer,
+                  bool              clear_z_buffer,
+                  framebuffer_info* fbi) {
+
+    if (clear_image_buffer) {
+        memset(fbi->img.buffer, 0, fbi->img.bytes);
+    }
+
+    if (clear_z_buffer) {
+        memset(fbi->z.buffer, 0, fbi->z.bytes);
+    }
+}
+
+
+
+void
+draw_span(uint32_t           base,
+          uint16_t           length,
+          fract *            attribs_start,
+          const fract *      attribs_steps,
+          int32_t            div,
+          framebuffer_info * fbi) {
+
+    uint8_t num_planes = fbi->num_attribs + 1;
+
+    unsigned int i;
+
+    /* Process each pixel in the span: */
+
+    for (i = 0; i < length; i++) {
+        int32_t z = MAX_Z - attribs_start[fbi->num_attribs].q;
+        uint32_t z_mask = -(~(z - fbi->z.buffer[base + i]) >> 31);
+        uint32_t n_z_mask = ~z_mask;
+
+        uint32_t j = base + i;
+        uint32_t k = j * num_planes;
+
+        unsigned int l;
+
+        /* The following statements will only have any effect if the depth
+           test, performed above, has suceeded. I. e. if the depth test fails,
+           no changes will be made on the framebuffer; otherwise, the
+           framebuffer will be updated with the new values.
+        */
+        fbi->z.buffer[j] = (fbi->z.buffer[j] & n_z_mask) | (z & z_mask);
+
+        for (l = 0; l < fbi->num_attribs; l++) {
+            fbi->img.buffer[k + l] =
+                (fbi->img.buffer[k + l] & n_z_mask) |
+                (attribs_start[l].q & z_mask);
+        }
+
+        fbi->img.buffer[k + fbi->num_attribs] =
+            (fbi->img.buffer[k + fbi->num_attribs] & n_z_mask) |
+            (fbi->maxval & z_mask);
+
+        /* Compute the attribute values for the next pixel: */
+
+        step_up(attribs_start, attribs_steps, num_planes, div);
+    }
+}
+
+